Cessna Single Engine High Wing Maintenance

 Explain procedures for replacement of unique components. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 6 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. SYSTEM OVERVIEW ATA Chapter 61 provides the maintenance practices of the propeller and spinner. Refer to the applicable McCauley service manual for information beyond the scope of the Cessna Maintenance Manuals. General Information The Skyhawk SP is equipped with a two bladed, fixed pitch metal propeller (model 1A170E). ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 7 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Propeller Maintenance Practices PROPELLER AND SPINNER (61-10-00) Removal/Installation Refer to section 61-10-00, Figure 201 for the Removal and installation of the propeller and spinner. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 8 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. PROPELLER AND SPINNER (61-10-00) Removal/Installation EXERCISE CARE Exercise care when working with the propeller. Ensure magneto switch is in the off position before turning propeller. Refer to Cessna Maintenance Manual Chapter 71, Cowling - Maintenance Practices for the removal and installation of the cowling and nose cap. Refer to McCauley Propeller Owner Operator Information Manual Table 1003 for Installation of Fix Pitch Propellers DOWEL PIN A dowel pin holds the propeller, aft bulkhead and spacer together when removed. Refer to ASTM E-1444 Magnetic Particle Testing or ASTM E-1417 liquid penetrant inspection, for inspecting the propeller mounting bolts or replace at every overhaul. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 9 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. PROPELLER AND SPINNER (61-10-00) Removal/Installation Replace the propeller mounting bolts in the event of a bird strike. SPACERS AND PROPELLERS The spacer and propeller are balanced as a pair and must be installed together. Do not exchange spacers or propellers from other airplanes. DOWEL LOCATION Final dowel location will be made when spacer is installed in propeller hub. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 10 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. PROPELLER AND SPINNER (61-10-00) Removal/Installation AFT BULKHEAD The aft bulkhead may need to be pushed forward slightly to engage spinner screws. It may be necessary to rotate the spinner 180 degrees for the best spinner and screw attach alignment. FORWARD BULKHEAD The mounting bolt holes in the forward bulkhead may be undersized due to the original torqueing of the mounting bolts. This may cause the spinner to bulkhead screws holes not to align. The required hole diameter for the forward bulkhead is 0.516 inch diameter to 0.527 inch diameter. If necessary, remove the forward bulkhead and enlarge bolt hole using a 33/64th (0.516 inch diameter) drill. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 11 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. PROPELLER AND SPINNER (61-10-00) Removal/Installation SPINNER SCREW HOLES If necessary, the spinner screw holes in the aft bulkhead flanges may be increased to 0.205 inch diameter for adjustment. TRIM SPINNER It is acceptable to trim the spinner a maximum of 0.08 inch. Trim spinner only if maximum adjustment does not allow adequate clearance. Trim as little as possible to obtain clearance. Apply corrosion protection. Refer to Chapter 20, Interior and Exterior Finish - Cleaning/Painting. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 12 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Propeller Inspection/Check Fixed pitch propellers - 2000 hours or 72 calendar months, whichever occurs first. Check the propeller mounting bolt torque at least once per year. Torque the propeller mounting bolts as per McCauley Propeller Owner Operator Information Manual to the following torque value:  Torque 1/2-Inch diameter fasteners to 55 to 65 Foot Pounds (660 to 780 Inch Pounds) per McCauley SB 227B. Refer to ASTM E-1444 Magnetic Particle Testing or ASTM E-1417 liquid penetrant inspection, for inspecting the propeller mounting bolts. Propeller mounting bolts must be replaced whenever the propeller is involved in a blade strike as defined in Necessary Actions Following Object Strike of Stationary Propeller, Blade Strike of Rotating Propeller, Birdstrike, or Sudden Engine Stoppage:  For 1A170E/JHA[XXXX] propellers only, installed on Aircraft Operating as Pilot Schools in accordance with 14 CFR, Part 141, and all aircraft with 2000 or more cycles for every 1000 flight hours must be inspected in accordance with Service Bulletin 240[X] every 1000 hours or 72 calendar months whichever occurs first. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 13 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FIXED PITCH PROPELLER (61-10-00) Limitations: Corrosion other than small areas of light surface corrosion with no evidence of pitting may require propeller removal and reconditioning by an appropriately rated repair facility. Intergranular corrosion may be present when the corrosion protective coatings (paint, anodize, etc.) have been lost. Corrosion pitting should be removed as described in the overhaul manual and applicable ADs. Unauthorized Straightening of Blades: A bent propeller cannot be straightened without special processing in an FAA approved Part 145 Propeller Repair Station or international equivalent because bending may harden the aluminum and lead to catastrophic blade failure. Blades showing evidence of unapproved repairs require removal of the entire propeller and proper assessment by an FAA approved Part 145 Propeller Repair Station or international equivalent. Blade Shortening: Propeller tip damage will lead field maintenance personnel to consider removing damaged material from the blade tips. Propellers certification is to the aircraft engine and airframe resonant frequency by designing it with a particular diameter to minimize vibration. Shortening of the blades without reference to approved data could create a condition that is NOT airworthy. Refer to the airplane type certificate data sheet, aircraft specification sheet, or supplemental type certificate data sheet as applicable, for the allowable propeller diameter for each propeller installation. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 14 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FIXED PITCH PROPELLER (61-10-00) Preflight inspections consist of the following criteria:  Oil and Grease Leakage  Blade Inspection o Surface Damage o Erosion o Straightness o Looseness  Spinner and Bulkhead  General Condition  Control System  Maintenance records ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 15 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FIXED PITCH PROPELLER (61-10-00) 100 Hour and Annual Inspection includes: Spinner removal Inspection of all attaching hardware Checking the propeller for corrosion, cracks, or other damage. Inspect entire propeller system for oil leakage. Repaint propeller blades, as necessary, in accordance with the instructions in Cleaning/Painting/Protective Treatments. Examine all placards for legibility and security of installation. Necessary Actions Following Object Strike of Stationary Propeller, Blade Strike of Rotating Propeller, Bird Strike, or Sudden Engine Stoppage includes the following: Propellers with Blades Bent Beyond Repair Object Strike of Stationary Propeller Object Strike is defined as any impact of a non-rotating propeller by a substantial moving object, such as any personnel vehicle, aircraft tug, ground power unit, or similar.  Inspect all blades for damage such as scrapes, gouges, etc. caused by the impact.  Check the blade track and verify that all blades measure within the following limits: 1. 0.0625 inch (1.6mm) of each other on piston engine propellers.  Check blade twist ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 16 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FIXED PITCH PROPELLER (61-10-00) LOG BOOK The results of an object strike inspection should be noted in the propeller log book and, if required, note when the next inspection is due.  If any propeller blade is damaged beyond field repair limits, the blade track or the propeller blade twist is beyond the limits, contact McCauley for disposition of the propeller assembly. DEFINITION The definition is for use as an example only. Determination as to whether or not an object strike actually occurred is ultimately the responsibility of the aircraft operator. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 17 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FIXED PITCH PROPELLER (61-10-00) Blade Strike of Rotating Propeller Blade Strike, sometimes referred to as "Ground Strike," is defined as any impact or suspected impact of the rotating propeller upon such items as, but not limited to, the ground, tow bars, landing lights, carts, snow banks, hedges, etc. INTERNAL DAMAGE Internal damage can occur without evidence of gross external damage. Any McCauley propeller experiencing a blade strike must be removed from the aircraft and overhauled by an FAA approved Part 145 Propeller Repair Station or international equivalent in accordance with the applicable overhaul manual. Bird strike: A bird strike is the impact of any bird into the rotating propeller causing damage.  Inspect all blades for damage such as scrapes, gouges, etc. caused by the impact. Refer to Blade Repair for field repair limits.  Check the blade track and verify that all blades measure within the following limits: 1. 0.0625 inch (1.6mm) of each other on piston engine propellers. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 18 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FIXED PITCH PROPELLER (61-10-00) BIRD STRIKE INSPECTION The results of a bird strike inspection should be noted in the propeller logbook and, if required, note when the next inspection is due. If any propeller blade is damaged beyond field repair limits or the blade track is beyond the limits, the propeller must be removed from the airplane and taken to and overhauled by an FAA approved Part 145 Propeller Repair Station or international equivalent. Sudden Engine Stoppage: Sudden Stoppage is any propeller experiencing a sudden decrease in RPM. This is commonly due to engine failure or seizure. Any McCauley propeller experiencing a sudden stoppage must be removed from the aircraft and overhauled by an FAA approved Part 145 Propeller Repair Station or international equivalent in accordance with the applicable propeller overhaul manual. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 19 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. System Review PROPELLER SYSTEM REVIEW When dressing the propeller, conduct visual inspections at normal inspection intervals. Damage or suspect damage found during an inspection, refer to McCauley Owners and Operators Manual MPC26 for inspecting the propeller. If damage is beyond the limits, as per MPC26, the propeller must be removed from service and sent to an approved propeller repair station. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 20 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Model Differences 206 DIFFERENCES - PROPELLER - MAINTENANCE PRACTICES (61-10-00) The 206 has a three-bladed, constant-speed metal propeller. The maintenance practices that follow include the removal and installation procedures of the spinner and propeller. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 21 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. SPINNER REMOVAL/INSTALLATION STANDING NEAR THE PROPELLER Do not stand or let anyone stand close to the propeller. Do maintenance as if the power to the propeller is always on. SPINNER MATERIAL REMOVAL Make sure you remove minimal spinner material as necessary to give minimum clearance between the spinner and the propeller blades. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 22 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. PROPELLER REMOVAL/INSTALLATION PROPELLER ASSEMBLY As the propeller assembly is separated from the engine crankshaft, oil will drain from the propeller and engine crankshaft cavities. Install the Propeller  When installing the spinner lightly press the spinner against the spinner stabilizer.  Examine the alignment of the mounting holes in the spinner with the holes in the spinner bulkhead assembly.  Without an increase of pressure on the spinner, the mounting holes in the spinner must be set approximated 0.050 inch forward of the true center of the holes in the spinner bulkhead assembly.  Add or remove spacers as necessary to set the holes in the correct position.  Push on the spinner until the spinner mounting holes are aligned with the spinner bulkhead assembly holes and install four screws and washers equally spaced around the circumference of the spinner. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 23 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - PROPELLER GOVERNOR- MAINTENANCE PRACTICES (61-20-00) The propeller governor is a single-acting, centrifugal type, which boosts oil pressure from the engine and directs it to the propeller where the oil is used to increase blade pitch. The governor is on the forward, upper left side of the engine. Maintenance practices include removal and installation of the propeller governor, high RPM stop adjustment, and rigging of the governor control. On the 206, the max propeller speed is 2500rpm and the propeller governor turns at .947 to 1 of the propeller. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 24 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. PROPELLER GOVERNOR REMOVAL AND INSTALLATION PROPELLER GOVERNOR REMOVAL/INSTALLATION  Exercise care when working with the propeller.  Always treat the propeller as if the ignition switch were on.  Do not stand, nor allow anyone else to stand, within the arc of the propeller.  Ensure magneto switch is in the off position before turning propeller. CONTROL CABLE WASHERS Identify washers and position of washers for use when reconnecting control cable to control arm. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 25 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. MAGNETO Ensure magneto is grounded before turning propeller. SPLINE ENGAGEMENT Do not force spline engagement. Rotate crankshaft slightly and splines will mesh smoothly when properly aligned. CASTELLATIONS Do not exceed 50 in-lbs when tightening nut to line up cotter pin hole with castellations in nut. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 26 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. HIGH RPM STOP SCREW ADJUSTMENT RPMS ON THE GROUND Due to climate conditions, field elevation, low pitch propeller blade angle, and other factors, an engine may not reach rated RPM on the ground. It may be necessary to read just the governor high RPM stop screw after test flying to obtain maximum rated RPM when airborne. Propeller Control Cable CONTROL CABLE The control cable is not repairable and must be replaced at every engine overhaul. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 27 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES - PROPELLER- MAINTENANCE PRACTICES MCCAULEY (61-10-00) The 182 has a three bladed, constant-speed, metal propeller. Maintenance practices consist of removal and installation of the:  Propeller  Spinner The 182 uses the same method as the 206 for shimming the propeller spinner. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 28 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. PROPELLER AND SPINNER REMOVAL AND INSTALLATION PROPELLER REMOVAL/ INSTALLATION  Exercise care when working with the propeller.  Always treat the propeller as if the ignition switch were on.  Do not stand, nor allow anyone else to stand, within the arc of the propeller.  Ensure magneto switch is in the off position before turning propeller. SPINNER REINSTALLATION Note number of shims for use during reinstallation of spinner. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 29 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. PROPELLER AND SPINNER REMOVAL AND INSTALLATION PROPELLER AND SPINNER  If equipped with prop deice system, remove brush block assembly before removing propeller, to prevent possible brush damage.  As the propeller assembly is separated from the engine crankshaft, oil will drain from the propeller and engine crankshaft cavities.  Without increasing pressure on spinner, the mounting holes in spinner need to be positioned approximated 0.050 inch (1.27 mm) forward of the true center of holes in spinner bulkhead assembly.  Use only the number of shims that will allow just enough alignment for screws to be installed while pushing hard against spinner. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 30 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES - PROPELLER GOVERNOR - MAINTENANCE PRACTICES (61-20-00) The propeller governor is a single-acting, centrifugal type, which boosts oil pressure from the engine and directs it to the propeller where the oil is used to increase blade pitch. The governor is on the forward, upper left side of the engine. The Max rpm for the propeller is 2400rpm and the propeller governor turns at .947 to 1 of the propeller. Maintenance practices include removal and installation of the propeller governor, high RPM stop adjustment, and rigging of the governor control. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 31 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES - PROPELLER GOVERNOR - MAINTENANCE PRACTICES (61-20-00) General Precautions GROUND THE MAGNETO Make sure you ground the magneto before you turn the propeller. Propeller Governor Removal WASHER POSITION Identify washers and position of washers for use when reconnecting control cable to control arm. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 32 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES - PROPELLER GOVERNOR - MAINTENANCE PRACTICES (61-20-00) Propeller Governor Installation SPLINE ENGAGEMENT Do not force the spline engagement. Rotate the crankshaft slightly and the splines will mesh smoothly when properly aligned. PROPELLER GOVERNOR INSTALLATION Do not exceed 50 inch-pounds. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 33 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES - PROPELLER GOVERNOR - MAINTENANCE PRACTICES (61-20-00) High RPM Stop Screw Adjustment RPM Due to climate conditions, field elevation, low pitch propeller blade angle, and other factors, the engine may not reach rated RPM on the ground. It may be necessary to readjust the governor high RPM stop screw after test flying to obtain maximum rated RPM when airborne. Propeller Control Cable Governor Control Rigging  During rigging, you must pull the governor control back approximately 0.125 inch and lock in this position. GOVERNOR CONTROL RIGGING This allows cushion, which will make sure there is full contact with the governor high RPM stop screw. ATA61 PROPELLERS FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 34 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES - PROPELLER GOVERNOR - MAINTENANCE PRACTICES (61-20-00) RPM STOP SCREW Do not exceed 50 inch-pounds. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 35 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ATA71 - Power Plant Overview LESSON OBJECTIVES  Explain safety precautions related to power plant  Explain maintenance practices important to the engine  Explain engine operations  Explain power plant indications Explain special tooling and test equipment used with Cessna High Wing Series Aircraft  Explain procedures for replacement of unique components ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 36 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. POWER PLANT SYSTEM OVERVIEW Cessna’s Maintenance Manual Chapter 71 provides description, troubleshooting and maintenance practices on the power plant and associated components. The Lycoming IO-360-L2A provide the power plant for the Skyhawk series airframe. For engine related information not found in this chapter, refer to applicable Textron Lycoming maintenance manuals. This section will cover the following procedures:  Power Plant Standard Practices  Power Plant Description and Operation  Power Plant Troubleshooting  Power Plant Maintenance Practices  Engine Cowl Maintenance Practices  Engine Mount & Isolator Maintenance Practices  Air Induction Removal and Installation ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 37 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Power Plant Standard Practices The Lycoming Operators Manual Chapter 70 Standard Practices provides the guidelines for removal and installation, inspection, cleaning and repairs. This chapter consists of the following sections:  Description  Specification  Operating Instructions  Periodic Inspections  Maintenance Procedures  Troubleshooting For more information, refer to the Lycoming Manuals ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 38 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Power Plant Description and Operation DESCRIPTION (71-00-01) The Lycoming IO-360-L2A engine is direct drive, four cylinder, fuel injected, horizontally opposed, and air cooled. The cylinders, numbered from front to rear and stagger to have individual throws on the crankshaft for each connecting rod. The right front cylinder is number 1 and cylinders on the right side of the engine are identified by odd numbers 1 and 3. The left front cylinder is number 2 and the cylinders on the left side are identified as 2 and 4. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 39 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE – INTERNAL (71-00-01) The Lycoming IO-360-L2A engine includes the following internal components and system: Valve Operating Mechanism Valve Operating Mechanism is a conventional type camshaft located above the crankshaft. The camshaft actuates hydraulic tappets, which operate the valves through push rods and valve rockers. The valve rockers are supported on full floating steel shafts. The valve springs bear against hardened steel seats and are retained on the valve stems by means of split keys. Crankshaft The crankshaft is made from a chrome nickel molybdenum steel forging. Connecting Rods The connecting rods are made in the form of “H” sections from alloy steel forgings. They have replaceable bearing inserts in the crankshaft ends and bronze bushings in the piston ends. Two bolts and nuts through each cap retain the bearing caps on the crankshaft ends. Pistons The pistons are machined from an aluminum alloy. The piston pin is of a full floating type with a plug located in each end of the pin. Depending on the cylinder assembly, pistons may be machined for either three or four rings and may employ either half wedge or full wedge rings. Consult the latest revision of Service Instruction No. 1037 for proper piston and ring combinations. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 40 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE – INTERNAL (71-00-01) Oil Sump The sump incorporates an oil drain plug, oil suction screen, mounting pad for carburetor or fuel injector, the intake riser and intake pipe connections. Lubrication System The lubrication system consist of an impeller type pump contained within the accessory housing actuates the full pressure wet sump lubrication system. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 41 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE – EXTERNAL (71-00-01) The Lycoming IO-360-L2A engine includes the following external components: Cylinders The cylinders are of conventional air-cooled construction with the two major parts, head and barrel. The heads are made from an aluminum alloy casting with a fully machined combustion chamber. Rocker shaft bearing supports are cast integral with the head along with housings to form the rocker boxes. The cylinder barrels have deep integral cooling fins and the inside of the barrels are ground and honed to a specified finish. Crankcase The crankcase assembly consists of two reinforced aluminum alloy castings, fastened together by means of studs, bolts and nuts. The mating surfaces of the two castings are joined without the use of a gasket, and the main bearing bores are machined for use of precision type main bearing inserts. Accessory Housing The accessory housing is made from an aluminum casting and is fastened to the rear of the crankcase and the top rear of the sump. If forms a housing for the oil pump and the various accessory drives. Cooling System These engines are designed to be cooled by air pressure. Baffles are provided to build up a pressure and force the air through the cylinder fins. The air is then exhausted to the atmosphere through a low pressure outlet located at the rear of the cowling. Induction System Lycoming O-360 and HO-360 series engines are equipped with either a float type or pressure type carburetor, refer to Lycoming Operator Manual Table 1 for model application. Particularly good distribution of the fuel-air mixture to each cylinder is obtained through the center zone induction system, which is integral with the oil sump and is submerged in oil, insuring a more uniform vaporization of fuel and aiding in cooling the oil in the sump. From the riser the fuel-air mixture is distributed to each cylinder by individual intake pipes. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 42 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE ACCESSORIES (71-00-01) ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 43 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE SPECIFICATIONS (71-00-01) Cessna’s Maintenance Manual Section 71-00-01 Table 1 provides the engine information pertaining to the IO-360-L2A engine. Refer to the Lycoming and Cessna Engine Manuals for more information pertaining to the IO-306-L2A engine. Lycoming IO-360-L2A Facts  Produces 2700 RPM's  Weighs 278 LBS including the fuel injection, ignition systems, starter, alternator and baffling.  Magneto Slick Model No. 4371 (fires at 25° BTDC)  Aviation grade fuel is 91/96 and 100 LL  Maximum oil consumption at 2400 RPM is .52 quarts per hour ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 44 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE – TROUBLESHOOTING (71-00-01) The troubleshooting charts listed in the Lycoming Troubleshooting Guide provides the proper procedures for troubleshooting engine malfunctions or failures and should be used in conjunction with Cessna’s Maintenance Manual Chapter 73, Fuel Injection System - Troubleshooting and Chapter 74, Ignition System The use of turbochargers and automatic controllers can complicate the troubleshooting procedures, always start by discussing the problem with the pilot and the facility management. Information from the crew will help narrow the problem by eliminating some of the probable causes. After collecting all the information observe the external condition of the engine for any indication of the problem. For example, look at are the intake and exhaust pipes for leaks, the ignition harness, breather, and the engine compartment for excessive oil stains, gas stains or exhaust stains. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 45 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE – TROUBLESHOOTING (71-00-01) Some procedures can contain more information for example:  A compression check to locate any low compression cylinders  A bore-scope inspection determines the condition of the combustion chamber and provide information such as: o The presence of excessive carbon deposits that may indicate high oil consumption o The lack of carbon deposits may indicate continuous lean engine operation or detonation and scratched or scored cylinder walls may indicate broken rings. o When inspecting the combustion chamber it may require to remove the spark plugs  Spectrometric oil analysis measures is a good trouble-shooting tool to measure engine effectiveness For the spectrometric oil analysis to be effective the engine must be in the analysis program for an extended period of time to develop a history of periodic samples of oil that were analyzed. Refer to applicable engine manuals and publications listed in Introduction for information beyond the scope of this chapter. Align airplane 90 degrees to the right of wind direction for static run-ups. Follow the procedures outlined in the Pilot’s Operating Handbook and FAA Approved Airplane Flight Manual for running the engine at full throttle. PISTON PIN PLUGS Always keep track of which piston pin plugs came out of which cylinder. During reassembly the piston pin plugs must be matched up with the cylinder they came out of. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 46 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE – TROUBLESHOOTING (71-00-01) LOW POWER If low power is suspected, the following static run-up procedures may be used in conjunction with the troubleshooting chart to develop a diagnosis: ATMOSPHERIC PRESSURE VARIANCE Variances in atmospheric pressure, temperature and humidity can have a significant impact on run- up RPM. Low static run-up RPM information should be used only in conjunction with other troubleshooting procedures to determine if a problem actually exists. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 47 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE – MAINTENANCE PRACTICES (71-00-01) Engine removal and installation This section provides the instructions to remove and install the engine and mount from the firewall. Refer to Cessna’s Maintenance Manual applicable engine publications for more information pertaining safety precautions and the removal and installation of the Engine. Refer to Cessna’s Maintenance Manual Chapter 61, Propeller - Maintenance Practices for removing and installing the propeller. Label the electrical wires on the low vacuum annunciator switches, low oil pressure transducer, and alternator. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 48 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE – MAINTENANCE PRACTICES (71-00-01) On airplanes with Garmin G1000, disconnect and reconnect the electrical connector from the tachometer sending unit. Engine Cleaning Use Stoddard solvent or equivalent chemicals to clean the engine. Ensure all openings have caps or plugs to prevent solvent entry into the engine and electrical accessories (starter, alternator, etc.) must have covers before the solvent is applied. Engine Storage Refer to Cessna’s Maintenance Manual Chapter 10, Storage - Description and Operation for preservation procedures ENGINE MOUNT REMOVAL PROCEDURE The procedures that follow remove the engine and mount from the firewall. If the engine is removed from the mount and the mount will stay attached to the firewall, some of the steps will not be necessary. To remove the engine from the mount, the four bolts that connect the four shock mounts to the engine mounting flange and the engine mount tube must be removed. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 49 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ENGINE – MAINTENANCE PRECAUTIONS (71-00-01) P LEAD WIRE When the P lead wire is disconnected from the magnetos to remove the electrical ground from the magneto circuit, the magnetos become electrically active. A ground wire must be connected to the magnetos or the high tension wires removed from the spark plugs to prevent accidental engine start when the propeller is turned. An accidental engine start can cause injury to persons in the area of the propeller. GARMIN G1000 Airplanes with Garmin G1000 have EGT probe at each cylinder. BOLT ACCESS It can be necessary to get access to the bolt heads from the inside of the cockpit. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 50 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Cowl DESCRIPTION (71-10-00) The engine cowl consists of upper and lower sheet metal halves and upper and lower composite nose pieces. Cowling shock mounts needs shimmed when installed. The maximum gap is .125 between the shock mount and the cowling. The Shock mount (snubber) is design to absorb the vibrations from the engine and prevent them from transferring to the airframe. Thus they do fatigue and the rubber cracks out. MAINTENANCE PRACTICES (71-10-00) The cowl attaches to the shock mounts using quick release, quarter turn fasteners to allow for easy removal and installation. The nose pieces are attached to each other using screws and nutplates. Refer to Cessna's Maintenance Manual Section 71-10-00 Figure 201 for removing and installing the cowls. Refer to Cessna's Maintenance Manual Section 71-10-00 Figure 202 replacing the mount and adjusting the shims For repair procedures to the cowl, refer to the Structural Repair Manual for repairing the cowl. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 51 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Air Induction System DESCRIPTION (71-60-00) Ram air to the engine goes into the induction air box through the induction filter in the forward part of the lower engine cowl. From the induction air box, the air is pointed to the inlet of the fuel/air control unit and through the intake runners of the related cylinders. MAINTENANCE PRACTICES (71-60-00) Refer to Cessna’s Maintenance Manual Section 71-60-00 Figure 201 for the removal and installation of the air induction system components. The induction air filter keeps dust and dirt from the induction system and must be kept in a good clean condition. More engine wear is caused through the use of a dirty or damaged air filter than is usually thought. The frequency with which the filter must be removed, examined and cleaned will be given by aircraft conditions of operation. The general practice is to remove, examine and clean the filter at least every 100 hours of engine operation time, and more frequently if given by the conditions of operation. Under very dusty conditions, daily servicing of the filter is recommended ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 52 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. MAINTENANCE PRECAUTIONS (71-60-00) FILTER ELEMENT CLEANING Be careful when the filter element is cleaned with compressed air. FILTER CASE Arrows on the filter case show the direction of normal airflow. FACE SCREEN The bond holds the paper pleats to the face screen and, if the bond is broken, the pleats are free to move and decrease filter operation. A face screen that is loose or has gaps shows that the bond is broken and the filter element must be replaced. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 53 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. MAINTENANCE PRECAUTIONS (71-60-00) SOLVENTS & CLEANING FLUIDS Do not use solvent or cleaning fluids to wash the filter. Use only a water and household detergent solution when washing the filter. FILTER ASSEMBLY The filter assembly can be cleaned with compressed air a maximum of 30 times or it can be washed a maximum of 20 times. FILTER REPLACEMENT A new filter must be installed at 500 hours of engine operation or one year, whichever occurs first. A new filter must be installed if the filter is damaged. FILTER PANELS The panels of the filter can have distortion when wet, but they will go back to their normal shape when dry. ATA71 DESCRIPTION FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 54 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Model Differences 182 DIFFERENCES - ENGINE - DESCRIPTION AND OPERATION (71-00-01) The 182T uses the Textron Lycoming IO-540-AB1A5. This engine is a direct-drive, six-cylinder, fuel-injected, horizontally- opposed, air-cooled engine. The T182T uses TIO-540-AK1A, a turbocharged version of the same design. The cylinders, numbered from front to rear, are staggered to permit a separate throw on the crankshaft for each connecting rod. The right front cylinder is number 1 and the other cylinders on the right side of the engine are identified by odd numbers 3 and 5. The left front cylinder is number 2 and the other cylinders on the left side are identified as 4 and 6. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 55 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES – DESCRIPTION AND OPERATION - ENGINE SPECS IO-540-AB1A5 Cessna’s Maintenance Manual Section 71-00-01, Table 1 provides the engine information pertaining to the IO-540- AB1A5 and the TIO-540-AK1A engine. Refer to the Lycoming and Cessna Engine Manuals for more information pertaining to the IO-540_AB1A5 and the TIO-540- AK1A engine. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 56 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - ENGINE SPECS IO-540-AC1A5 &TIO-540-AJ1A The engine used on the 206 is the Textron Lycoming IO-540- AC1A5 and the turbocharged TIO-540-AJ1A engine. Cessna’s Maintenance Manual Section 71-00-01 Table 1 provides the engine information pertaining to the IO-540- AC1A5 and the TIO-540-AJ1A engine. Refer to the Lycoming and Cessna Engine Manuals for more information pertaining to the IO-540-AC1A5 and the TIO-540- AJ1A engine. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 57 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES - ENGINE - DESCRIPTION (71-00-01) The component locations on the ID-540-AB1A5 and TIO-540-AK1A differ from components on the IO-360-L2A used on the 172. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 58 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES - ENGINE - DESCRIPTION (71-00-01) Identify 182 component locations for parts that differ from the 172. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 59 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182 DIFFERENCES - ENGINE - DESCRIPTION (71-00-01) Identify 182 component locations for parts that differ from the 172. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 60 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - ENGINE - DESCRIPTION (71-00-01) The Textron Lycoming IO-540-AC1A5 is a direct-drive, six-cylinder, fuel-injected, horizontally-opposed, air-cooled engine. The TIO-540-AJ1A is a turbocharged version of the same design. The cylinders, numbered from front to rear, are staggered to permit a separate throw on the crankshaft for each connecting rod. The right front cylinder is number 1 and the other cylinders on the right side of the engine are identified by odd numbers 3 and 5. The left front cylinder is number 2 and the other cylinders on the left side are identified as 4 and 6. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 61 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - ENGINE - DESCRIPTION (71-00-01) Identify 206 component locations for parts that differ from the 172. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 62 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - ENGINE - DESCRIPTION (71-00-01) Identify 206 component locations for parts that differ from the 172. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 63 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - ENGINE - DESCRIPTION (71-00-01) ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 64 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - ENGINE – MAINTENANCE PRACTICES (71-00-01) For engine removal and installation follow the steps outlined in 71-00-01 of the maintenance manual. Engine Removal Differences  For airplanes with standard avionics, disconnect the electrical connector from the EGT Probe (on non- turbocharged airplanes) or disconnect the electrical connector from the TIT Probe (on turbocharged airplanes) and then disconnect the electrical terminal from the CHT probe.  For airplanes with Garmin G1000 avionics, disconnect the EGT and the CHT thermocouple connectors. Engine and Mount Installation Differences.  For airplanes with standard avionics, connect the electrical connector to the EGT Probe (on non- turbocharged airplanes) or connect the electrical connector to the TIT Probe (on turbocharged airplanes).  For airplanes with standard avionics, connect the electrical terminal to the CHT probe.  For airplanes with Garmin G1000 avionics, connect the EGT and the CHT thermocouple connectors. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 65 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - ENGINE MOUNT - MAINTENANCE PRACTICES (71-20-00) The 206 engine mount assembly uses four rubber mounts to isolate engine noise and vibration. (Left photo) The shock mounts for the 206 (Left photo) connect the engine to the engine mount assembly and are made of rubber and metal construction and assembled in a sandwich to isolate noise and vibration from the cabin area. Nuts should be torqued from 450 to 500 inch-pounds upon installation. For the 172 and the 182 - The dynafocal engine mount is made of 4130 steel and uses four rubber mounts to isolate engine noise and vibration from the engine mount. The mount is attached to the fuselage at four points on the firewall using bolts, washers and nuts. (Right photo) ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 66 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - INDUCTION AIR FILTER SYSTEM - MAINTENANCE PRACTICES (71-60-00) Ram air to the engine enters the induction air box through the induction air filter, located on the upper right side of the engine. From the induction air box, the air is directed to the inlet of the fuel/air control unit and, ultimately, through individual intake runners into their respective cylinders. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 67 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - ENGINE DRAIN SYSTEM- MAINTENANCE PRACTICES (71-70-00) Different components in the engine compartment have drain lines to let fluid and/or fumes escape.  The drain lines are attached with hose clamps and fittings.  The routing of the drain lines are on the left and right sides of the lower cowl.  Line removal and installation have clamps, fittings and hoses that are connected together to make the routing.  You must examine the drain lines to make sure of the correct routing and condition when you remove and install the components.  Some airplanes have an optional cylinder drain can installed. The cylinder drain can is designed to catch the fuel that drains from the engine cylinders at shut down.  If a cylinder drain can has not been installed and you want to install one, you must obtain MK206-71-02 for instructions. ATA71 POWER PLANT FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 68 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 206 DIFFERENCES - ENGINE DRAIN SYSTEM- MAINTENANCE PRACTICES (71-70-00) ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 69 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ATA73 - Fuel Injection System Overview LESSON OBJECTIVES  Provide a simple description of the whole subject, using common words and examples, using typical terms and identify safety precautions related to the airframe, its systems and power plant  Identify aircraft manuals, maintenance practices important to the airframe, its systems and power plant  Define the general layout of the fuel injection system  Define the general layout and characteristics of the fuel injection system  Identify special tooling and test equipment used with the fuel injection system ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 70 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. OVERVIEW Cessna's Maintenance Manual Chapter 73 provides a description of the RSA Fuel Injection system used on the IO- 360-L2A. Refer to the Model Series Structural Repair Manual for repair of structural members and repair techniques used throughout the airplane. General Information  The fuel injection system is a low pressure, multi nozzle, continuous flow system which injects raw fuel into the engine cylinder heads.  The injection system applies the principle of measuring engine air consumption to control fuel flow.  More air flow through the venturi will result in more fuel being delivered to the engine, and less air flow through the venturi results in a decreased flow of fuel to engine. This section will cover the following procedures:  Fuel Injection Troubleshooting  Fuel Injection Maintenance Practices  Fuel indicator Maintenance practices ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 71 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Fuel Injection System Description and Operation DESCRIPTION (73-00-01) Fuel from the wing tanks supplies fuel to the fuel injection system through a series of lines, valves and pumps. From the engine-driven fuel pump, fuel enters the fuel/air control unit, passes through the fuel distribution valve, and is routed to individual injection nozzles at each cylinder. For a schematic of the entire fuel system, refer to Chapter 28, Fuel Storage and Distribution - Description and Operation, Figure 1. The Fuel Injection system consist of the following components:  Fuel/Air Control Unit - Also known as the 'servo regulator,’ is located on the underside of the engine and integrates the functions of measuring airflow and controlling fuel flow. The control unit consists of an airflow sensing system, a regulator section and a fuel metering section.  Fuel Distribution Valve - Also known as a 'spider’ or a flow divider, is located on top of the engine and distributes fuel evenly to the four cylinders once it has been regulated by the fuel/air control unit. The fuel distribution valve attaches to the fuel distribution valve, which feeds into a pressure transducer. This transducer measures fuel pressure and translates that reading into fuel flow at the cockpit indicator.  Injection Nozzles (4 total) - Each cylinder contains an injection nozzle, also known as an air bleed nozzle or a fuel injector. Nozzle incorporates a calibrated jet that determines, in conjunction with fuel pressure, the fuel flow entering each cylinder. Fuel entering the nozzle is discharged through the jet into an ambient air pressure chamber within the nozzle assembly. The nozzle assembly also contains a calibrated opening which is vented to the atmosphere, and allows fuel to be dispersed into the intake portion of the cylinder in an atomized, cone-shaped pattern. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 72 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL INJECTION SYSTEM – OPERATION (73-00-01) The wing tanks store and is deliver fuel to the fuel injection system through a series of lines, valves and pumps. From the engine-driven fuel pump, fuel enters the fuel/air control unit, passes through the fuel distribution valve, and is routed to individual injection nozzles at each cylinder. Refer to Cessna’s Model 172 Maintenance Manual Chapter 28 Fuel Storage and Distribution - Description and Operation, Figure 1 for a schematic of the entire fuel system. The fuel/air control unit is the heart of the injection system and occupies the position ordinarily used by the carburetor at the engine intake manifold inlet. Operation of the fuel injection system is based on the principle of measuring airflow and using the airflow signal to operate a servo valve. The accurately regulated fuel pressure established by the servo valve, when applied across the fuel control system, makes fuel flow proportional to airflow. The fuel/air control unit is comprised of an integrated airflow sensing system, a regulator section and a fuel metering section. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 73 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL INJECTION SYSTEM – OPERATION (73-00-01) The Airflow Sensing System consists of a throttle body which houses the air throttle valve, the venturi, and servo valve and fuel control unit.  Differential pressure between impact air and the venturi throat pressure is a measurement of the velocity of the air entering the engine.  Pressures are vented through drilled channels in the throttle body to both sides of an air diaphragm and create a force across the diaphragm. A change in air throttle position or a change in engine speed will change the air velocity, which in turn changes the force across the air diaphragm. The Regulator Section contains the air diaphragm mentioned in the preceding paragraph and a fuel diaphragm.  Fuel inlet pressure is applied to one side of the fuel diaphragm.  The other side of the fuel diaphragm is exposed to fuel that has passed through the metering jet (metered fuel pressure).  The differential pressure across the fuel diaphragm is referred to as the fuel metering force.  The air metering force applied to the air diaphragm is transmitted through the regulator stem and tends to move the ball valve in the opening direction.  The fuel metering force across the fuel diaphragm acts to oppose the air metering force and tends to close the ball valve. Because the air forces are very low in the idle range, a constant head idle spring is provided to maintain an adequate fuel metering force at low rpm.  As the air metering force increases, the spring compresses until the spring retainer touches the air diaphragm and acts as a solid member.  The constant effort spring produces a force which provides a smooth transfer from idle to low power cruise operation. Whenever the air metering, fuel metering and spring forces are balanced, the ball valve maintains a fixed position. The Fuel Metering Section is contained within the throttle body casting and consists of an inlet fuel screen, a rotary idle valve and a rotary mixture valve. Both idle speed (closed throttle position) and idle mixture (relationship between throttle position and idle valve position) may be adjusted externally to meet individual engine requirements.  Idle valve is connected to the throttle valve by means of an external adjustable link and controls fuel flow through the low speed range of operation and is adjustable to obtain good idling characteristics without affecting fuel metering in the high power range.  Mixture control valve gives full rich mixture on one stop and a progressively leaner mixture as it is moved toward idle cutoff.  The full rich stop defines sea level requirements and the mixture control provides for altitude leaning ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 74 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL SERVO INTERNAL AIRFLOW (73-00-01) The Fuel Injection Systems meters fuel in direct ratio to the volume of air being consumed by the engine at any given time, which is accomplished by sensing Venturi suction and impact air pressures in the throttle body. Opening or closing the throttle valve results in a change in the volume of air being drawn into the engine, which results in a change in the velocity of air passing across the impact tubes and through the venturi. When air velocity increases, the pressure at the impact tubes remains relatively constant depending upon the inlet duct configuration, air figure location, etc. The pressure at the Venturi throat decreases. Which creates a differential (impact minus suction) used over the entire range of operation of the fuel injection system as a measurement of the volume of air consumption. Reciprocating engines operate most efficiently in a very narrow range of air to fuel or fuel/air ratios. The injection system uses the measurement of air volume flow to generate a usable force which to regulate the flow of fuel to the engine in proportion to the amount of air being consumed. This is accomplished by channeling the impact and Venturi suction pressures to opposite sides of a diaphragm. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 75 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL SERVO EXTERNAL PARTS (73-00-01) ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 76 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. OPERATION - CRUISE CONDITION (73-00-01) The two opposing forces (fuel and air differentials) are equal, and the regulator servo valve (which connects both diaphragms by a stem) is kept ata a fixed position that allows discharge of just enough metered fuel to maintain pressure balance. If the throttle is opened to increase power, air flow immediately increases. This results in an increase in the pressure differential across the air diaphragm to a theoretical value of "3”. Immediate result is a movement of the regulator servo valve to the right. This increase servo valve opening causes a decrease in pressure in the metered fuel chamber in the metered fuel chamber and an increase in fuel pressure differential across the main metering jet. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 77 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. OPERATION - CRUISE CONDITION (73-00-01) When the fuel differential pressure force reaches a value of "3” (equaling the air diaphragm force) , the regulator stops moving and the servo valve stabilizes at position, which will maintain the balance of pressure differentials, i.e., air and fuel equalizing 3. The servo valve does not meter fuel. The servo valve controls pressure differential across the metering jet. The engine delivers metered fuel through the fuel injector servo unit through a system that includes a flow divider and a set of discharge nozzles (one nozzle per cylinder). The flow divider consists of the following components:  Valve  Sleeve  Diaphragm Spring The primary functions of the flow divider are:  Assure equal distribution of metered fuel to the nozzles at and just above idle  Provide isolation of each nozzle from all the others for clean engine shut down Fuel discharge jet within the fuel nozzle is sized to accommodate the maximum fuel flow required at the rated horsepower As the engine accelerates, it gradually moves the flow divider valve open against the spring pressure. The “V” slot opening to each engine nozzle is greater than the area of the fuel restrictor in the nozzle. The metered fuel is assumed by the nozzles. Cylinders with restricted nozzles will be running lean and remaining cylinders will be rich. Flow divider can be disassembled in the field for cleaning and inspection. When connected to the tester, the flow divider valve should almost open immediately (1/2 psig) ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 78 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. MIXTURE CONTROL (73-00-01) The external idle valve allows the mechanic to properly tune for the proper idle mixture. Idle mixture is correct when the engine gains approximately 25 to 50 rpm from its idle speed setting as the mixture control is placed in cut off. The Venturi in the idle range, the air metering force is not sufficient to accurately control fuel flow (not enough negative Venturi pressure). ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 79 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. OPERATION - FUEL SYSTEM (73-00-01) The manual mixture control (sliding valve) can be used by the pilot to effectively reduce the size of the metering jet. To maintain a differential pressure across the metering jet in proportion to the volume of air flow effective size. Constant head idle spring augments the force of the air diaphragm in the idle and off idle range. The idle spring assures that the regulator servo valve is open sufficiently to allow fuel being metered by the idle valve to flow out to the flow divider. As airflow increases above idle the air diaphragm begins to move to the right in response to increasing air pressure differential. The idle spring will compress until its retainer guide contacts the diaphragm plate. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 80 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. OPERATION - FUEL SYSTEM (73-00-01) From this point, in terms of air flow, fuel flow, or power the constant head idle spring assembly is a solid member moving with the air diaphragm and exerts no force on its own. The constant head spring is furnished on a selection of strengths so the overhaul technician can properly calibrate the injector for idle fuel flow and for the transition to servo regulator controlled fuel flow. The transition from idle to servo regulator controlled fuel flow has to be supplemented with a constant effort spring. This spring assists the air diaphragm to move smoothly from the low air flow idle range to the high power range. A center body seal assembly separates the air section from the fuel section. Leakage through the center body seal causes extremely rich operation and poor cut off. The presence of raw fuel out the impact tubes indicates seal leakage. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 81 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. OPERATION - FUEL NOZZLE (73-00-01) Normally aspirated requires the simple nozzle assembly with the air bleed screen and shroud press in. The air bleed type nozzles discharge fuel inside the nozzle body into a vented chamber. The exit is always exposed to manifold pressure, which on a normally aspirated engine is always less atmospheric, which results in air being drawn in through the air bleed and mixed with fuel in the fuel/air chamber to provide for fuel atomization. This is important to the idle and low power ranges where manifold pressure is weakest and bleed air intake is greatest. Plugged air bleed in this range allows the exit of the fuel restrictor to be exposed to manifold suction that effectively increases the pressure differential across the restrictor and causes an increase if fuel flow through that nozzle. Since this nozzle is in effect, stealing fuel from the other nozzles, this cylinder will run rich and the other cylinders will be correspondingly lean. A net decrease in metered fuel pressure will result and show up on the flowmeter as a lower fuel flow indication. Refer to the RSA Fuel Injection Training Manual for the Comparison Check procedures. Over torque of the nut connecting the fuel line to the nozzle can result in pressing the insert deeper into the body and closing off the air bleed on older nozzles. Over torque can crack the flange off the insert on the newer type nozzles. Torque nut to 25 to 50 inch- pounds. Over torque the nozzles into the cylinder head results in distortion of the base of the nozzle and upsets its calibration and spray pattern. Torque nozzle at 60 inch-pounds. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 82 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL INJECTION SYSTEM – MAINTENANCE PRACTICES (73-00-01) Cessna’s Maintenance Manual Section 73-00-01 provides instructions for removal/installation, adjustment and cleaning of various components used in the fuel injection system. Refer to Cessna’s Maintenance Manual section 73-00-01 and Lycoming Maintenance Manual section 73-00-00) for maintenance information beyond the scope of this section. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 83 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL INJECTION SYSTEM – MAINTENANCE PRACTICES (73-00-01) Always observe the following general precautions and rules during fueling, defueling, fuel bay purging, repairing, assembly or disassembly of system components, and electrical system checks and repairs on the airplane fuel system. Plugs or caps should be placed on all disconnected hoses, lines and fittings to prevent residual fuel drainage, thread damage, or entry of dirt or foreign material into fuel system. Flush system any time fuel system is opened with 1/2 gallon of fuel at the inlet of servo and flow divider using the fuel boost pump. Keep all parts clean and free of contaminants when working on fuel injection system. Make a note number and position of washers for reinstallation when removing the mixture and throttle control linkages from control unit. Torque nuts in a crisscross (opposite) pattern to 90 inch-pounds and then re-torque nuts in the same manner to a final torque value of 180-200 inch pounds. Refer to Cessna’s Maintenance Manual Chapter 76 Throttle Control - Maintenance Practices, Figure 201 and Chapter 76, Fuel Mixture Control - Maintenance Practices and Figure 201 for an illustration of washer and linkage sequence when installing mixture and throttle control linkages. Cotter Pin Hole Do not back the nuts off to line the cotter pin hole up with the castellation’s in the nut. Torque each nut to 30 inch-pounds and then proceed tightening the nut until the cotter pin hole lines up with the castellation in each nut. Do not exceed 50 inch-pounds. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 84 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL INJECTION SYSTEM – MAINTENANCE PRACTICES (73-00-01) Refer to Cessna’s Model 172 Maintenance Manual Chapter 71, Cowling - Maintenance Practices for removing and installing the engine cowls. The Fuel Injection System Maintenance practices consist of the following tasks.  Fuel Distribution Valve  Injection Nozzles Lubricants Use only fuel-soluble lubricants (such as engine oil) on the nozzle threads during installation. Idle Speed and Mixture Adjustment Refer to Cessna’s Model 172 Maintenance Manual Chapter 73 Section 73-00-01 Figure 201 for adjustment procedures. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 85 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL INJECTION SYSTEM – MAINTENANCE PRACTICES (73-00-01) Propeller and Propeller Blast During adjustment procedure stay clear of propeller and/or propeller blast to avoid possible injury or death. Precision Airmotive Service Letter SIL RS-67 For additional information in conjunction with procedures below, refer to the Precision Airmotive Service Letter SIL RS-67. Oil Temperature It may not be possible to get an oil temperature of 150°F (65°C) at cooler ambient temperatures. In that condition, it will be necessary to set the idle speed and mixture at a lower temperature. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 86 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL INJECTION SYSTEM – MAINTENANCE PRACTICES (73-00-01) Fuel Mixture To aid in the adjustment of the fuel mixture, the clevis on the fuel servo has an L (lean) and R (rich) stamp on it to indicate the direction that the thumb wheel should be moved to enrich the fuel mixture and increase the RPM rise. Turn the thumb wheel in the opposite direction you will lean the fuel mixture and decrease the RPM rise. After each adjustment is made, the engine speed should be increased to approximately 1800 RPM and held for approximately 10 to 15 seconds to clean the spark plugs and clear the cylinders of excess fuel. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 87 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL INJECTION SYSTEM – MAINTENANCE PRACTICES (73-00-01) Fuel Mixture 2 If the mixture was excessively rich or lean when this procedure was started the engine speed will require readjustment as the fuel mixture is adjusted to the desired value. Set the idle speed to the specified RPM after the mixture has been set to get the 10 to 50 RPM rise a lean condition. Idle Speed and RPM changes. Small changes in the idle speed and RPM are permitted. Find the cause of any large variations in RPM. Injector Nozzle Cleaning Refer to Cessna’s Model 172 Maintenance Manual Chapter 5, Inspection Time Limits for the injector nozzles and fuel strainer cleaning intervals. Refer to Cessna’s Model 172 Maintenance Manual Chapter 5, Inspection Time Limits for the air throttle shaft lubrication intervals ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 88 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. TROUBLESHOOTING (73-00-01) Refer to Cessna's Model 172 Maintenance Manual Section 73-00-01, Table 101 for trouble shooting the fuel injection system. The trouble shooting procedures consist of the following malfunctions:  High Fuel Flow Reading Unsatisfactory  Fuel Cutoff.  Engine Will Not Increase to the Necessary Rpm Rough Idle.  Low Takeoff Fuel Flow.  Engine Is Difficult To Start.  Engine Operates Rough. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 89 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. INJECTION NOZZLE FLOW TEST (73-00-01) If nozzle plugging is suspected, disconnect injector lines at the nozzles. Cap nozzles with clean valve stem caps to protect nozzles from contamination during removal Refer to Injection Nozzles Removal/Installation. Pull up injector lines taking care that lines are not kinked. Install nozzles back into lines and torque from 25 to 50 inch-pound. Using clear containers (bottles with graduations are preferred) flow fuel into containers using aircraft boost pump and observe nozzle discharge pattern. When the mixture control is placed in the full rich position the nozzles should display a pencil stream pattern. The nozzles should also flow the same amount of fuel from cylinder to cylinder. If an unusual flow pattern or an unequal amount of fuel is noted in any of the containers the nozzles should be thoroughly cleaned. Refer to Injector Nozzle Cleaning. After cleaning install clean protective valve stem caps. It is recommended that after cleaning the nozzles, they be reinstalled in the injector lines and a nozzle flow check is conducted to verify that the nozzles are clean. Following a successful flow check reinstall the protective flow caps and reinstall the nozzles in the cylinders and torque from 55 to 60 inch-pound. Remove protective caps and reinstall injector lines to the nozzles and torque from 25 to 50 inch-pound. Perform leak check ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 90 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL SYSTEM ADJUSTMENTS (73-00-01) Idle Speed and Mixture Adjustment Refer to Cessna's Model 172 Maintenance Manual Section 73-00-01 Figure 201 for adjustment procedures. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 91 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL SYSTEM ADJUSTMENTS (73-00-01) Idle Speed and Mixture Adjustment Propeller and Propeller Blast During adjustment procedure stay clear of propeller and/or propeller blast to avoid possible injury or death. Precision Airmotive Service Letter SIL RS-67 For additional information in conjunction with procedures below, refer to the Precision Airmotive Service Letter SIL RS-67. Ensure that the alternate air door is closed during this adjustment. Run engine until the oil temperature increases to 150°F (65°C). ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 92 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL SYSTEM ADJUSTMENTS (73-00-01) Idle Speed and Mixture Adjustment Oil Temperature It may not be possible to get an oil temperature of 150°F (65°C) at cooler ambient temperatures. In that condition, it will be necessary to set the idle speed and mixture at a lower temperature. With the mixture control in the full rich position, set the idle speed to 675 RPM, +25 or -25 RPM. Advance the throttle to approximately 1800 RPM and immediately return it to idle. Idle speed should be approximately the same as set above. Adjust the fuel mixture control by rotating the knob counterclockwise, toward lean, quickly for approximately one inch, then very slowly until the peak RPM is obtained and the engine speed starts to drop off. Note the difference between the starting RPM and the peak RPM. This is the lean rise.  If the rise is less than 10 RPM it is necessary to enrichen the fuel mixture.  If the rise is more than 50 RPM it is necessary to lean the fuel mixture. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 93 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL SYSTEM ADJUSTMENTS (73-00-01) Idle Speed and Mixture Adjustment Adjustment of the Fuel Mixture To aid in the adjustment of the fuel mixture, the clevis on the fuel servo has an L (lean) and R (rich) stamp on it to indicate the direction that the thumb wheel should be moved to enrichen the fuel mixture and increase the RPM rise. Turn the thumb wheel in the opposite direction you will lean the fuel mixture and decrease the RPM rise. Adjust the thumb wheel to set a rise 10 to 50 RPM.  If the adjustment thumb wheel bottoms out on the blocks, center it as follows:  Measure the distance between the two blocks. Disconnect the spring from the linkage pin.  Remove the cotter pin, linkage pin, wave washer, and flat washer.  Turn the block and adjustment screw until the adjusting thumb wheel is centered.  The distance between the blocks should measure the same as above.  Install the linkage pin, flat washer, wave washer, cotter pin, and spring. After each adjustment is made, the engine speed should be increased to approximately 1800 RPM and held for approximately 10 to 15 seconds to clean the spark plugs and clear the cylinders of excess fuel. Put throttle in idle position. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 94 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. FUEL SYSTEM ADJUSTMENTS (73-00-01) Idle Speed and Mixture Adjustment Repeat the procedure until you get the desired RPM rate change at idle. Engine Speed Readjustment If the mixture was excessively rich or lean when this procedure was started the engine speed will require readjustment as the fuel mixture is adjusted to the desired value. Set the idle speed to the specified RPM after the mixture has been set to get the 10 to 50 RPM a lean rise condition. Operate engine to full throttle and back to idle to make sure that the setting has not changed. Idle Speed and RPM Changes Small changes in the idle speed and RPM are permitted. Find the cause of any large variations in RPM ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 95 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Fuel Flow Indicator MAINTENANCE PRACTICES OVERVIEW (73-30-00) The fuel flow indicator maintenance practices consist of the removal and installation of the following components: EGT/Fuel Flow Gage  The fuel flow gage is on the right half of the dual-function EGT/Fuel Flow gage on the left side of the instrument panel.  On NAV III airplanes, fuel flow is displayed in the MFD. Transducer  Refer to Cessna's Model 172 Maintenance Manual Section 73-30-00 Figure 202 for the removal and installation of the transducer for airplanes with Garmin G1000.  Refer to Cessna's Model 172 Maintenance Manual Chapter 71, Cowling - Maintenance Practices for the removal and installation of the engine cowls.  Make sure that the arrow on the transducer shows the correct direction of flow. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 96 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Fuel Injection System Review Fuel from the wing tanks supplies fuel to the fuel injection system through a series of lines, valves and pumps. From the engine-driven fuel pump, fuel enters the fuel/air control unit, passes through the fuel distribution valve, and is routed to individual injection nozzles at each cylinder. The Fuel Injection system consist of the following components:  Fuel/Air Control Unit - Also known as the 'servo regulator,’ is located on the underside of the engine and integrates the functions of measuring airflow and controlling fuel flow.  The control unit consists of an airflow sensing system, a regulator section and a fuel metering section.  Fuel Distribution Valve - Also known as a 'spider’ or a flow divider, is located on top of the engine and distributes fuel evenly to the four cylinders once it has been regulated by the fuel/air control unit.  The fuel distribution valve attaches to the fuel distribution valve, which feeds into a pressure transducer. This transducer measures fuel pressure and translates that reading into fuel flow at the cockpit indicator.  Injection Nozzles (4 total) - Each cylinder contains an injection nozzle, also known as an air bleed nozzle or a fuel injector. o Nozzle incorporates a calibrated jet that determines, in conjunction with fuel pressure, the fuel flow entering each cylinder. o Fuel entering the nozzle is discharged through the jet into an ambient air pressure chamber within the nozzle assembly. o The nozzle assembly also contains a calibrated opening which is vented to the atmosphere, and allows fuel to be dispersed into the intake portion of the cylinder in an atomized, cone-shaped pattern. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 97 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Model Differences 182/206 DIFFERENCES - FUEL INJECTION SYSTEM (73-00-01) The fuel injection system is a low pressure, multi-nozzle, continuous flow system that injects raw fuel into the engine cylinder heads. The injection system is based on the principle of measuring engine air consumption to control fuel flow. More airflow through the Venturi results in more fuel flowing to the engine, and less airflow through the Venturi results in a decreased flow of fuel to engine. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 98 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182/206 DIFFERENCES - FUEL INJECTION SYSTEM (73-00-01) System components include the:  Fuel/Air Control Unit  Fuel Distribution Valve (Flow Divider)  Injection Nozzles (6 Total)  Lines Used o Connect the Components 182 Fuel Distribution Valve  The fuel distribution valve is a rigid line which feeds into a pressure transducer.  This transducer measures fuel pressure and translates that reading into fuel flow at the cockpit indicator. This is not applicable to NAV III airplanes. 206 Fuel/Air Control Unit  Fuel flows from the servo, through the fuel flow transducer, to the distribution valve, and out to the fuel nozzles.  On turbocharged airplanes, a fuel flow transducer attached to the aft right baffle and connected to the fuel inlet line measures flow. The fuel injection system for the 182 aircraft is located in the bottom section of the engine bay. Operation: Fuel is stored in the wing tanks and moves to the fuel injection system via a series of lines, valves and pumps. From the engine driven fuel pump, fuel enters the fuel/air control unit, passes through the fuel distribution valve, and routes to individual injection nozzles at each cylinder. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 99 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182/206 DIFFERENCES - FUEL INJECTION SYSTEM (73-00-01) 206 - Maintenance Practices:  Fuel/Air Control Unit Removal/Installation  Fuel Distribution Valve Removal/Installation  Injection Nozzles Removal/Installation  Injection Nozzle Flow Test  Idle Speed and Mixture Adjustment  Injector Nozzle Cleaning  Fuel Strainer Cleaning  Air Throttle Shaft Lubrication  Engine Driven Fuel Pump Pressure Setting (T206) 182 – Maintenance Practices  Fuel/Air Control Unit Removal/Installation  Fuel Distribution Valve Removal/Installation  Injection Nozzles Removal/Installation  Injection Nozzle Flow Test  Idle Speed and Mixture Adjustment  Injector Nozzle Cleaning  Fuel Strainer Cleaning  Air Throttle Shaft Lubrication  Engine Driven Fuel Pump Pressure Setting (T182) Maintenance practices for the 182 are the same as for the 172 with one additional step to set the pressure of the engine driven fuel pump. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 100 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182/206 DIFFERENCES - FUEL INJECTION SYSTEM (73-00-01) The fuel injection system for the 206 aircraft is located in the top mid section of the engine bay. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 101 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182/206 DIFFERENCES - FUEL INJECTION SYSTEM (73-00-01) The RSA 10-ED1 fuel injection system installed on the Cessna 206 does not have an automatic mixture control.  Therefore, it is necessary for the pilot to lean the mixture to maintain proper fuel burn and engine temperatures.  The bullet type Venturi installed in the center of the throttle bore in the RSA 10 systems could house an automatic mixture control (AMC) however no Cessna 206 aircraft use a AMC configuration.  Therefore, the internal housing has no AMC on the bullet type Venturi, and simply channels impact air to the air diaphragm and Venturi suction air to the opposite side of the same diaphragm.  The air and fuel diaphragms and the rest of the fuel injection system operate in the same manner as in the 182 and the 172. ATA73 FUEL INJECTION SYSTEM FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 102 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. 182/206 DIFFERENCES - FUEL INJECTION SCHEMATIC (73-00-01) ATA74 IGNITION FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 103 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. ATA74 - Ignition Overview LESSON OBJECTIVES  Explain safety precautions related to the engine ignition system  Explain maintenance practices important to the engine ignition system  Explain normal system operations  Explain system indications  Explain special tooling and test equipment used with Cessna High Wing Series Aircraft  Explain procedures for replacement of unique components ATA74 IGNITION FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 104 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. SYSTEM OVERVIEW - ENGINE IGNITION (74-00-00) The Lycoming IO-360-L2A engine uses two Unison/Slick 4371 series, impulse-coupled magnetos to fire two spark plugs in each cylinder. The left magneto fires the upper left and lower right spark plugs, and the right magneto fires the lower left and upper right spark plugs. Normal operation utilizes both magnetos due to the more complete burning of the fuel/air mixture with dual ignition. A rotary-type switch located on the left switch and control panel controls ignition and starter operation. The MAGNETOS switch positions are OFF, R, L, BOTH, and START. Switch positions: Operate the engine on both magnetos (BOTH position) except for magneto checks. The R and L positions are for checking purposes and emergency use only. Rotating the MAGNETOS switch to the spring-loaded START position, with the MASTER switch in the ON position, the starter contactor closes and the starter, now energized, will crank the engine. Releasing the switch will automatically return it to the BOTH position. ATA74 IGNITION FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 105 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. Ignition System Maintenance Practices IGNITION SYSTEM TROUBLESHOOTING (74-10-00) Troubleshooting charts for the following conditions are available in the Cessna Model 172 AMM (74-10-00):  Engine will not start  Engine will not idle or run properly ATA74 IGNITION FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 106 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. IGNITION SYSTEM TROUBLESHOOTING (74-10-00) P LEAD Make sure that each magneto P lead is grounded. PROPELLER ROTATION Before you rotate the propeller remove a minimum of one spark plug from each cylinder to prevent the start of the engine. For complete description, operation, troubleshooting, maintenance, overhaul and lubrication requirements of the magnetos, refer to the Lycoming Direct Drive Engine Overhaul Manual, Lycoming Operators Manual, Lycoming Service Instruction 1437 and the Unison 4300/6300 Series Magneto Maintenance and Overhaul Manual. ATA74 IGNITION FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 107 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. MAGNETO REMOVAL/INSTALLATION (74-10-00) Refer to Cessna’s Maintenance Manual Chapter 74 Section 74-10-00 for the removal and Installation of the magnetos. Refer to Cessna’s Maintenance Manual Chapter 71 for remove and install the ring cowl. PROCEDURE The removal and installation for each magneto is typical. ATA74 IGNITION FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 108 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. MAGNETO REMOVAL/INSTALLATION (74-10-00) P LEAD Make sure that each magneto P lead is grounded. PROPELLER ROTATION Before you rotate the propeller remove a minimum of one spark plug from each cylinder to prevent the start of the engine. Disengage the high tension cover from the magneto. For a reference point when you install the magneto, turn the propeller in the normal direction until each impulse coupling releases near Top Dead Center (TDC) on the number one cylinder compression stroke. ATA74 IGNITION FOR TRAINING PURPOSES ONLY SEHW MX Date 2016AUG11 Page | 109 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. MAGNETO REMOVAL/INSTALLATION (74-10-00) IMPULSE COUPLING You will hear a click sound from the impulse couplings when they release. The crankshaft position can be found by the marks on the front or aft face of the starter ring gear support.  Marks on the front face of the ring gear, they must be aligned with the small hole that is found at the two o'clock position on the front face of the starter housing.  Marks on the aft face of the ring gear, they must be aligned with the engine case parting line. Turn the propeller in the opposite direction of the normal propeller operation to approximately 30 degrees BTDC (Before Top Dead Center) on the number one cylinder compression stroke. Turn the propeller in the normal direction to 25 degrees BTDC on the number one cylinder compression stroke. Disconnect the P lead and ground wire from the magneto. Examine the magneto angle to help make sure you put it in the same position for installation. Install the Magneto  Apply a small quantity of silicone grease such as DC4 to each side of the new magneto base gasket, which will help future timing adjustments.  Make sure the magneto drive gear is installed correctly, the nut torqued correctly and the cotter pin is installed. ATA74 IGNITION FOR TRAINING PURPOSES ONLY SEHW MX Date 2017JAN19 Page | 110 © 2017 TRU Simulation + Training, a Textron Company Export Classification C, ECCN EAR99 All Rights Reserved. MAGNETO REMOVAL/INSTALLATION (74-10-00) T-118 TIMING PIN Make sure you remove the T-118 timing pin immediately after you attach the magneto to the accessory case and before the magneto or propeller is turned. Insert the T-118 timing pin into the left or right timing hole in the magneto distributor block, depending on rotation of the magneto. Turn the magneto rotor in the opposite of normal direction until the timing pin engages fully into the distributor gear. If the magneto rotor does not move freely and the pin will not go into the hole in the gear, the pin has hit the pointer on the gear. Pull the pin out far enough to continue to turn the magneto freely in the opposite direction of normal movement until the pointer has passed the pin, and then insert the pin. Turn the magneto rotor until the pin engages the gear. Do a check of the crankshaft to make sure the propeller has not moved and is still set in position with the number one cylinder at 25 degrees BTDC (Before Top Dead Center) on the compression stroke. If the propeller has been turned and only one magneto was removed, it will be necessary to engage the impulse coupling on the magneto that is installed, and establish the crankshaft position. With the number one cylinder at 25 degrees BTDC on the compression stroke, do the steps that follow. Install the magneto with the new base gasket and the T-118 timing pin in position. Engage the magneto drive gear with the engine gear, in a position that will give a range of magneto ti