SERVICE MANUAL AND INSTRUCTIONS FOR CONTINUED AIRWORTHINESS FOR THE WIPAIRE MODEL 8750 AMPHIBIOUS/SEAPLANE FLOAT ON THE CESSNA MODEL 208/208B CARAVAN

5.1 BLEEDING THE HYDRAULIC SYSTEM ...................................................................................................... 69 CHAPTER 6 WATER RUDDER ................................................................................... 71 6.0 BASIC DESCRIPTION .............................................................................................................................. 72 CHAPTER 7 ELECTRICAL .......................................................................................... 75 7.0 ELECTRICAL SYSTEM ............................................................................................................................. 76 SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 8 of 104 Revision D CHAPTER 8 TKS SYSEM EQUIPPED AIRCRAFT REQUIREMENTS ............... 79 8.0 TKS SYSTEM .......................................................................................................................................... 80 BASIC DESCRIPTION.................................................................................................................................... 80 CHAPTER 9 RECOMMENDED PROCESSES, PRODUCTS AND INSP. CHECKLISTS .................................................................................................................. 81 9.0 SERVICING INSTRUCTIONS .................................................................................................................... 82 9.1 CORROSION REMOVAL ......................................................................................................................... 84 9.2 MAINTENANCE CHECKLIST .................................................................................................................... 85 9.3 FLOAT REMOVAL AND RE‐INSTALLATION GUIDE ................................................................................... 90 9.4: WEIGHING PROCEDURES FOR CESSNA 208/208B, CARAVAN ................................................................ 96 CHAPTER 10 TROUBLESHOOTING ......................................................................... 97 CHAPTER 11 INSTALLATION PRINT INFORMATION ..................................... 101 CHAPTER 12 AIRCRAFT INSTALLED PERFORMANCE ITEMS AND DECRIPTIONS .............................................................................................................. 103 12.1 WING FENCES ................................................................................................................................... 104 12.2 VORTEX GENERATORS ...................................................................................................................... 104 12.3 FLOAT SUCTION BREAKERS ............................................................................................................... 104 SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 9 of 104 P/N 1005723 Doc. No. W8750-24-01 THIS PAGE INTENTIONALLY LEFT BLANK SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 10 of 104 Revision D LIST OF FIGURES FIGURE 1-1: FRONT VIEW CESSNA 208 CARAVAN ............................................ 15 FIGURE 1-2: TOP & SIDE VIEWS CESSNA 208 CARAVAN ................................. 16 FIGURE 1-3 FRONT VIEW CESSNA 208B CARAVAN ........................................... 17 FIGURE 1-4: TOP & SIDE VIEWS CESSNA 208B CARAVAN .............................. 18 FIGURE 1-5: FLOAT TERMINOLOGY ..................................................................... 19 FIGURE 1-6: MAINTENANCE ACCESS POINTS .................................................... 20 FIGURE 1-7: HYDRAULIC ........................................................................................... 22 FIGURE 3-1: NOSE WHEEL & BOX .......................................................................... 35 FIGURE 3-2: NOSE WHEEL GREASING .................................................................. 37 FIGURE 3-3: NOSE GEAR & BOX ITEMS ................................................................ 40 FIGURE 4-1: MINIMUM BRAKE ................................................................................ 43 FIGURE 4-2: MAIN GEAR, LOWER .......................................................................... 46 FIGURE 4-3: MAIN GEAR GREASING POINTS ..................................................... 48 FIGURE 4-4A: MAIN GEAR ADJ. DOWN ................................................................. 50 FIGURE 4-4B: MAIN GEAR ADJ. DOWN ................................................................. 51 FIGURE 4-5: MAIN GEAR ADJ. UP............................................................................ 52 FIGURE 4-6: MAIN GEAR DOWN STOP ADJ.......................................................... 53 FIGURE 4-7: ROTARY ACTUATOR .......................................................................... 62 FIGURE 4-8: MAIN SHOCK STRUT .......................................................................... 63 FIGURE 6-2: WATER RUDDER/STEERING ............................................................ 73 FIGURE 6-3: WATER RUDDER/STEERING ............................................................ 74 SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 11 of 104 P/N 1005723 Doc. No. W8750-24-01 THIS PAGE INTENTIONALLY LEFT BLANK SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 12 of 104 Revision D NEW CUSTOMER INFORMATION Customer Name Billing Address Shipping Address Phone Number Fax Number Purchasing Contact Phone Number E‐Mail Fax Number Accounts Payable Contact Phone Number E‐Mail Fax Number Type(s) of Aircraft Owned or Maintained Model(s) of Floats and Skis Owned or Maintained FedEx and/or UPS account number (if applicable) Please return to Wipaire Customer Service: Fax 651‐306‐0666 Phone 651‐306‐0459 CustomerService@wipaire.com SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 13 of 104 P/N 1005723 Doc. No. W8750-24-01 THIS PAGE INTENTIONALLY LEFT BLANK SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 14 of 104 Revision G CHAPTER 1 INTRODUCTION AND GENERAL INFORMATION 1.0 INTRODUCTION This manual is provided for the owners of Wipaire model 8750 Floats as installed on the Cessna 208 Caravan and 208B Grand Caravan. It has two main priorities: To inform owners of the level and amount of servicing required to properly maintain their floatplane, and to provide technical data and servicing as specified to maintenance professionals charged with servicing the floats. The service products referred to throughout this manual are described by their trade names and may be purchased from the Wipaire Parts Department. When performing standard repairs for Wipline Aluminum Floats, please refer to the “Structural Repair Manual For Wipline Aluminum Floats” part number 1008274. It is available free of charge online at www.wipaire.com. We, at Wipaire, welcome your purchase and look forward to years of satisfying exchanges with you. Your floats are built with pride and attention to detail, but we want that care to extend beyond your purchase. Our customer service department is available for your questions 24 hours a day, 7 days a week, where ever you are in the world. Parts Sales and Technical Support Dept: Wipaire, Inc. 1700 Henry Avenue – Fleming Field South St. Paul, MN 55075 Telephone: (651) 306-0459 Fax: (651)-306-0666 Website: www.wipaire.com Email: CustomerService@wipaire.com In this service manual we have worked hard to include many repair scenarios in addition to the recommended products, practices, and routine maintenance required to keep your floats in working order. When a float part is significantly changed or an additional inspection is recommended or required, often a service letter and/or kit is issued. If a warranty is issued, most commonly it is for an 18 month time period, so it is crucial to check for service letters specific to your float model at each periodic inspection to be eligible. Service Manuals and the installation prints included are also revised periodically and also to be kept updated. Service letters, Service Kits and Service Manuals are available on our web site at no charge, www.wipaire.com. NOTE: IT IS CRITICAL TO CHECK FOR MANUAL UPDATES EACH TIME AN INSPECTION IS EXECUTED. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 15 of 104 P/N 1005723 Doc. No. W8750-24-01 FIGURE 1-1: FRONT VIEW CESSNA 208 CARAVAN SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 16 of 104 Revision IR FIGURE 1-2: TOP & SIDE VIEWS CESSNA 208 CARAVAN SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision B Page 17 of 104 P/N 1005723 Doc. No. W8750-24-0 FIGURE 1-3 FRONT VIEW CESSNA 208B CARAVAN SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 18 of 104 Revision B FIGURE 1-4: TOP & SIDE VIEWS CESSNA 208B CARAVAN SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 19 of 104 P/N 1005723 Doc. No. W8750-24-01 FIGURE 1-5: FLOAT TERMINOLOGY SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 20 of 104 Revision IR FIGURE 1-6: MAINTENANCE ACCESS POINTS SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision B Page 21 of 104 P/N 1005723 Doc. No. W8750-24-01 1.1 GENERAL FLOAT INFORMATION The model 8750 amphibious float is an all aluminum structure. The alloy used throughout is mostly corrosion resistant 6061-T6, with 2024-T3 and 7075-T651 used in strength critical fittings and panels. Interior parts are cleaned, acid-etched and then primed prior to being riveted for enhanced corrosion resistance. Exterior surfaces are cleaned, alodine is applied as a corrosion resistant barrier, and then primed and custom painted. Model 8750 floats contain sixteen (16) water tight compartments per hull. Access to the inside of the floats for cleaning, inspection and repairs is through the access covers on the float deck and the access covers inside the wheel well. Figures 1-1 and 1-2 show three view drawings of the Cessna 208 as installed on Wipline model 8750 amphibious floats. Figures 1-3 and 1-4 show three view drawings of the Cessna 208B as installed on Wipline model 8750 amphibious floats. As a part of the float installation, the following additional changes are made to the landplane: 1. The hydraulic landing gear retraction system components and cockpit controls are added 2. The landing gear emergency gear operation hand pump and system are added 3. A water rudder steering system is installed 4. Auxiliary Vertical Fins (Finlets) are added 5. A seaplane extended chord rudder is installed 6. TKS pod & reservoir (if equipped) is removed Operational information is detailed in the Cessna 208 Airplane Flight Manual Supplement or Cessna 208B Airplane Flight Manual Supplement. Actual displacement for each float in fresh water is: Amphibian: at 100% Buoyancy = 8240 pounds at 80% Reserve = 9155 pounds Seaplane: at 100% Buoyancy = 8741 pounds at 80% Reserve = 9712 pounds SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 22 of 104 Revision C LANDING GEAR The landing gear incorporated within the amphibious floats is a retractable quadricycle type with two swiveling nose (or bow) wheels and four (4) (two (2) dual sets) of main wheels. Shock absorption is provided by air-oil shock struts on the two main landing gear assemblies and composite flat springs on the nose gear assemblies. Each main wheel is equipped with a hydraulically-actuated disc brake. Landing gear extension and retraction is accomplished by two (2) electrically-driven hydraulic pumps and four (4) hydraulic actuators (one (1) for each gear). The hydraulic pumps are located in the aircraft empennage and can be accessed by removing the aft cabin bulkhead. The hydraulic actuators are located adjacent to each gear. Hydraulic system fluid level should be checked at 25-hour intervals and should be serviced to levels in accordance with the installed placard using MIL-H-5606 (red) hydraulic fluid. The fluid level placard (Figure 1-7) is installed on the forward hydraulic Reservoir. FIGURE 1-7: HYDRAULIC FLUID LEVEL PLACARD The nose wheels are fully castoring for maneuverability while the airplane is under engine power or being towed. The main landing gear has dual 6:00x6 8-ply tires and the nose gear has a single 5:00x5 10- ply tire. All tires must be approved to TSO C62, type III. Differential use of the main- wheel brakes steers the aircraft on land. Item Fluid Type Qty. Main Gear Shock Strut MIL-H-5606 975 +/- 20 mL 33 +/- 0.75oz. Main Gear Shock Strut Nitrogen or Air 425 +/- 25 psi Main Gear Tires Nitrogen or Air 60 +0/- 5 psi Nose Gear Tires Nitrogen or Air 60 +/- 5 psi Hydraulic Pump reservoir MIL-H-5606 A/R per placard FIGURE 1-8: FLUID TYPES AND QUANTITIES SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 23 of 104 P/N 1005723 Doc. No. W8750-24-01 LANDING GEAR CONTINUED Grease zerks are provided in many locations that have pivoting joints. Greasing is recommended at 25 hour intervals, or more often depending on operating environment, with HCF Grease or equivalent. See Figure 3-2 for nose gear grease zerk locations. See Figure 4-3 for main gear grease zerk locations. STRUT PACKAGE The strut package attaches the floats to the aircraft. The strut package is comprised of the forward struts, main pylons, rear cross-wires, and front cross wires (or flying wires). The streamlined struts are made from extruded aluminum alloys. The main pylon is built from machined aluminum trusses, internal ribs, and skinned with aluminum sheet. WATER RUDDERS The floats are equipped with water rudders attached at the rear of the float structure. These rudders steer when the floats are in the water. Rudder controls are integrated into the existing aircraft rudder system and should move in the same direction as the air rudder. Water rudders are extended and retracted with a handle installed to the right of the pilot seat. Water Rudder & Springs SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 24 of 104 Revision IR 1.2 CLEANING The outside of the float should be kept clean by washing with fresh water and soap. Special care should be taken to remove engine exhaust trails, water-line marks, and barnacle deposits. After salt water operations, washing with fresh water should be done daily with special attention paid to hard to reach places like: - skin seams - wheel well areas - float attach points - hardware Alternatively, water taxiing in fresh water at step-speed can help flush the floats themselves, but additional rinsing should be conducted on struts and fittings. The float interior should be flushed out, especially if salt water or polluted water gets inside the compartments. If the floats are being stored inside a building either installed on the aircraft or not, it is strongly recommended to remove the inspection covers so the interior of the floats can dry out. Even without direct contact with saltwater, this hydraulic pump in the aircraft fuselage has severely corroded due to being in a saltwater environment without being kept clean. OPERATORS IN SALT WATER ARE STRONGLY CAUTIONED RINSING THE AIRCRAFT AND FLOATS WITH FRESH WATER AT THE END OF EACH DAY IS CRITICAL. ADHERING TO THESE CLEANING RECOMMENDATIONS ARE VITAL FOR KEEPING CORROSION TO A MINIMUM. FAILURE TO CLEAN THOROUGHLY CAN SEVERLY SHORTEN THE LIFE OF THE FLOATS. SALT WATER, POLLUTED WATER AND THEIR ENVIROMENTS, ARE STRONGLY AND DIRECTLY LINKED TO CORROSION AND MUST BE HANDLED PRO ACTIVELY. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 25 of 104 P/N 1005723 Doc. No. W8750-24-01 1.3 CORROSION Corrosion is the process by which metals are turned into oxides. It is a natural and ultimately unavoidable chemical reaction that is accelerated by dissimilar metals in contact with each other, and enclosed spaces and contaminants like dirt and exhaust deposits that hold moisture against the metal. If that moisture is salt water or fresh water that is polluted, it conducts the electrolytes better and the process of corroding is faster. Most aircraft and most floats are made out of aluminum due to its strength to weight ratio, and its ability to withstand fatigue and remain field repairable. Steel is used for strength in hardware and landing gear parts, and these are often areas where these dissimilar metals cause corrosion. Areas where moisture and dirt mix and stay wet against metal are common sites of oxidation. Float strut attach points, water rudders, and skin joints are examples of areas where this occurs. CORROSION HOT SPOTS - DISSIMILAR METAL CONTACT LIKE LANDING GEAR, FLAOT ATTACH POINTS AND OTHERS. - ENCLOSED SPACES THAT STAY MOIST LIKE LANDING GEAR FLAOT INTERIORS, SKIN LAP- JOINTS, AND OTHERS. - CONTAMANINATES ON THE METAL LIKE DIRT, SALT, ENGINE EXHAUST AND OLD OR OTHERWISE COMPRISED GREASE SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 26 of 104 Revision C 1.3 CORROSION (CONT.) Cladding, plating, anodizing, painting, greasing and waxing are all processes used to help protect metal from corrosion; Wipaire uses all these techniques during manufacture. But due to the rugged way our floats are used and the environment, these surface sealers become abraded or wear away, leaving the metal exposed. Removal of corrosion is detailed more fully in Chapter 9, but there are a few things an owner can do to stop the spread of corrosion and minimize the damage. Aside from the already detailed cleaning and inspection procedures, an anti-corrosion spray like Corrosion X, or its equivalent, should be used liberally. Because it has the ability to displace moisture and contaminants, it can be used when the floats are still wet or when they are dry. Periodically, hardware should be covered with waterproof grease. Especially in a salt water environment, bolts should be removed at least once a year and grease applied to the shafts, bolt/screw heads, and nuts. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 27 of 104 P/N 1005723 Doc. No. W8750-24-01 1.4 FLOAT HANDLING & JACKING To jack the floats for servicing tires, brakes, or doing retraction tests, it is recommended that a floor type jack (three ton minimum.) be used if lifting apparatus is not available . These jacks are commonly used for truck repair. The jack should be positioned on the keel centerline on the first bulkhead forward of the step. The jack should contact the keel squarely and if room permits, slip a board between the jack and keel. CAUTION! Due to critical angle of aircraft when single float jacking; check that wing fuel tank valves are confirmed closed, if possible use wing tie rope from float side to be jacked and tie off to tug. Raise the float slowly; making sure the aircraft stays balanced. After raising, block up the keel in several places and lower the jack. Raise only one float at a time with the opposite float wheels chocked. Position a sawhorse under main and after body keel to keep aircraft from tipping fore and aft. TOWING When towing the amphibian aircraft, two lugs are provided on the lower forward side of the nose spring. A rigid “V” frame can be fabricated to attach to these lugs for towing the aircraft with a tractor. Wipaire parts has this tow bar available for purchase. HOISTING Hoisting the aircraft can be performed using a lifting apparatus that attaches to the aircraft with lifting rings which are installed at the wing spar joints. Contact Wipaire Parts for details if necessary to remove or install floats LEVEL The level reference for the Caravan is two jig located nut plates and screws installed on left side of fuselage below side windows and forward of cargo door. Weight and balance information should be taken with aircraft in a level attitude. The float deck is at a 4 degree nose-down incidence from the aircraft level reference. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 28 of 104 Revision IR 1.5 MOORING For land operations, the aircraft is equipped with three fixed mooring points. Two are located on the outboard edge of the wing struts and the other is located on the underside of the tail section of the aircraft. Mooring Procedure on Land: 1. Position the aircraft near mooring location and it point into the wind. 2. Set the parking brake and/or chock the main wheels. 3. Install the aircraft control column lock. 4. Install the flight control gust lock. 5. Tie down the aircraft to anchor points on the ground. 6. Install provided engine inlet covers, pitot tube covers, and propeller anchor assembly. 7. Attach a static ground cable to one of the aircraft tie-down eyelets and the ground anchor point. For water operations, the floats are equipped with two deck cleats on each float, one forward near the pilot/copilot doors, and one aft near the cargo door. Mooring Procedure on Water at Dock: 1. Position the aircraft near the dock and point into the wind as much as able. 2. Install the control column lock. 3. Install the flight control gust lock. 4. Tie down using both deck cleats to secure aircraft to dock and keep it from moving if wind direction shifts. Mooring Procedure on Water at Buoy: 1. Position the aircraft near buoy. 2. Install the control column lock. 3. Install the flight control gust lock. 4. Tie to buoy using one deck cleat and leave sufficient slack in the rope so that the aircraft can move as the wind direction shifts without causing damage to aircraft. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 29 of 104 P/N 1005723 Doc. No. W8750-24-01 THIS PAGE INTENTIONALLY LEFT BLANK SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 30 of 104 Revision IR CHAPTER 2 AIRWORTHINESS LIMITATIONS SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 31 of 104 P/N 1005723 Doc. No. W8750-24-01 AIRWORTHINESS LIMITATIONS This Airworthiness Limitations section is FAA approved and specifies maintenance required under paragraphs 43.16 and 91.403(c) of the Federal Aviation Regulations unless an alternative program has been FAA approved. The aircraft Airworthiness Limitations are unchanged as a result of installation of the amphibious floats and the associated systems addressed by this STC. FAA APPROVED_________________________ DATE_________________________ SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 32 of 104 Revision IR THIS PAGE INTENTIONALLY LEFT BLANK SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 33 of 104 P/N 1005723 Doc. No. W8750-24-01 CHAPTER 3 NOSE GEAR SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 34 of 104 Revision IR 3.0 NOSE GEAR The nose gear consists of composite fiberglass beams that are attached on top to a moving carriage and on the bottom to blocks that caster. Inside the block is a castoring pin that is set into the machined fork assembly; the castoring pin allows the nose wheel to pivot 360 degrees. Geometry is such that no shimmy dampers are necessary. The nose gear has an over-center down lock. Retraction occurs when pressure is applied to the forward face of the actuator piston and the carriage is drawn along the tracks in the nose box. Gear position light proximity switches are closed when the piston (containing magnetic material) has reached either end of its travel. Refer to Figure 3.1 for visual reference The nose gear has single 5:00 x 5 10-ply tire. All tires must be approved to TSO C62, type III. NOSE WHEEL AND TIRE REMOVAL To remove each nose wheel 1. Jack the aircraft, completely lifting both hulls. It is not recommended to jack only one hull. 2. Cut cotter pin and remove axle nut. 3. Remove the AN4 bolt securing the opposite side of the axle. 4. Pull/Push the axle through the side plate. (either direction) taking care to set spacers aside as they are removed. 5. Wheel will drop out between side plates once axle has been removed a sufficient distance. Each nose wheel is a split-type rim. To remove the tire: 1. Remove air from tire. 2. Remove six (6) bolts that hold the wheel together. 3. Split rim and remove tire and tube. Nose tires should be replaced when the tread is worn through in any area. Reinstallation is the reverse of removal. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 35 of 104 P/N 1005723 Doc. No. W8750-24-01 FIGURE 3-1: NOSE WHEEL & BOX SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 36 of 104 Revision IR 3.1 ADJUSTMENT/TEST NOSE GEAR Refer to Figure 3.1 for visual reference. Adjustment of actuator stroke is provided at the ends of the piston rods. The length of the nose gear rod is adjusted such that the over-center knuckle (brass) rollers just bottom out on the down side and the piston just bottoms out on the mounting flange. The up stops nests in the up-stop pins. Nose gear proximity switches are located on clips that are mounted on the outer cylinder body, one on each end. The most forward switch is for the gear down lights and most aft is for the gear up position lights. Set the proximity switch mounting clip along outer cylinder body to a position such that the light goes out when the over-center track is about ¼ inch from bottomed position while traveling in the up direction. Lights should come on about 1/8 inch from the bottomed position while traveling in the down direction. The cylinder piston has a magnet that will activate the proximity switches. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 37 of 104 P/N 1005723 Doc. No. W8750-24-01 3.2 NOSE GEAR BASIC SERVICING Refer to Figure 3-2 for visual reference. The nose gear pivot assembly should be cleaned and inspected every 25 hours or more frequently whenever in water for an extended period of time, especially saltwater. Tracks and blocks should be cleaned and left dry or alternately cleaned and wiped with a rag with dry silicone spray on it. The nose wheels contain grease nipples for the wheel bearings. They should be greased every 25 hours. Nose tires are standard 5:00 x 5, 10-ply, inflated to 60 +/- 5 psi. All tires must be approved to TSO C62, type III. FIGURE 3-2: NOSE WHEEL GREASING SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 38 of 104 Revision IR 3.3 NOSE GEAR DISASSEMBLY (In float or removed from float) Items refer to areas on Figure 3-3 1. Disconnect hydraulic lines. Item 1 2. Remove the 4, NAS1103-2 bolts and washers attaching the Nose Ram, Item 2, to the flange assembly, Item 3, and slide the Nose Ram off of the flange assembly. 3. Inspect interior bore of the Nose Ram for corrosion and pitting. 4. Loosen AN316-10R Jam Nut, Item 4, on Nose Ram Rod End, Item 5. 5. Using a strap wrench or other suitable, non- marring tool, unthread the Ram, Item 6, from the Nose Ram Rod End. Do not attempt to remove the ram piston top (brass) from the ram shaft (stainless steel). They are assembled as a unit and permanently secured. 6. Remove Ram Assembly, Item 3, if desired to replace the T-seals, Item 10, felt wiper, Item 7, and plastic wiper, Item 8. 7. Replace T-seals on the Nose Ram, Item 9, and Ram Assembly, Item 3, if necessary. The T-Seal in the Cylinder End-Cap, Item 11, can be replaced by removing the NAS1103-2 bolts and removing the cap from the Cylinder. 8. Slide the Trolley, Item 12, out bottom of nose gear track. 9. If worn or damaged, replace the 4 Slide Blocks, Item 13, and the 2 Track Rollers, Item 14. 10. Grease the 2 axles, Items 15 & 16, when reassembling. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 39 of 104 P/N 1005723 Doc. No. W8750-24-01 3.4 NOSE GEAR ASSEMBLY Items refer to areas on Figure 3-3 1. Insert the Ram Assembly, Item 6, into the Flange Assembly, Item 3, if removed during disassembly. 2. Slide the Trolley, Item 12, with installed blocks and rollers into nose box track from bottom. 3. Pull forward on the Link, still attached to the Rod End, Item 5, to place the rollers, Item 14, into the down lock pocket on the nose box track. 4. Thread the Ram Assembly, Item 6, onto the Rod End, Item 5, until the ram piston contacts the Flange Assembly, Item 7, while at the same time the rollers are seated in the down lock pocket. Both the piston and the rollers need to bottom out against their respective mating parts at the same time. 5. Tighten the AN316-10R jam nut against the rod end. 6. Install the Nose Ram, Item 2, onto the Flange Assembly, Item 3, being careful not to nick T-Seals on bolt holes. Fasten with NAS1103-2 bolts and necessary washers. 7. Oil felt wiper through oil cup on the Flange assembly, Item 3. 8. Connect hydraulic lines to cylinder and cycle gear to fill cylinder with fluid. 9. Service hydraulic system with Mil-H-5606 if necessary. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 40 of 104 Revision IR FIGURE 3-3: NOSE GEAR & BOX ITEMS SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 41 of 104 P/N 1005723 Doc. No. W8750-24-01 THIS PAGE INTENTIONALLY LEFT BLANK SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 42 of 104 Revision IR CHAPTER 4 MAIN LANDING GEAR BRAKES & GEAR RETRACTION SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision F Page 43 of 104 P/N 1005723 Doc. No. W8750-24-01 4.0 GENERAL The main landing gear incorporated within the amphibious floats are retractable, quadricycle type with four main wheels in a dual tire formation. Air-oil shock struts on the two main landing gear assemblies provide shock absorption. The main landing gear has dual 6:00 x 6 8-ply tires. All tires must be approved to TSO C62, type III. The gear system is hydraulically actuated and driven by two hydraulic pumps. Brakes are hydraulic and there is a caliper on each main wheel. BRAKE REMOVAL & INSPECTION Each main wheel has a dedicated brake caliper. To remove the brake caliper: 1. Remove two mounting bolts on each caliper. 2. Compress the caliper piston using a c-clamp. 3. Slide caliper off of the brake disc. Brake pads should be replaced when the minimum section thickness is less than 0.100”, see Figure 4-1. Generally, the brake discs should be checked for wear, grooves, deep scratches, and excessive pitting. Pitting deeper than 0.015” or thickness below 0.327” is cause for replacement. MAIN WHEEL AND TIRE REMOVAL AND INSPECTION To remove each main wheel: 1. Remove brake caliper. 2. Drain oil from the axle by removing the plug in the hub cap of the inboard wheel. 3. After oil drains, remove snap ring and hub cap. 4. Cut cotter pin and remove axle nut. 5. Pull wheel off of axle. Each main wheel is a split-type rim. To remove the tire: 1. Remove air from tire 2. Remove 3 bolts that hold wheel together 3. Split rim and remove tire and tube Inspect an oil sample taken from the axle. Look for signs of bearing wear including metal shavings or other impediments in the oil. If the oil sample is clean and there are no abnormalities with the wheel spinning, further inspection including removing the wheel only needs to be done at the inspector’s discretion. Note: Some grease may show up in the oil sample as a result from grease used by the wheel manufacturer. Grease does not affect the wheel bearing lubrication, but oil may be changed to flush loose grease from the system if desired. Main gear tires should be replaced when the tread is worn through in any area. Reinstallation is the reverse of removal for tires, wheels, and brakes. FIGURE 4-1: MINIMUM BRAKE LINING THICKNESS SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 44 of 104 Revision IR MAIN GEAR/WHEEL ALIGNMENT There is no way to adjust the alignment within each main gear wheel set. If the tires are showing signs of abnormal/unsymmetric wear, some component has likely been worn/bent. Starting with the axle, examine each main gear component and mounting point for signs of damage/deformation. Replace damaged components once found. If no gear/bulkhead/airframe components are found to be damaged, use the following procedure to align left and right floats: 1. Move aircraft to level surface, ensure both nose wheels are facing aft (i.e. positioned for forward motion) 2. Measure the length of the forward flying wires, from the aft face of the clevis on each end. These distances should be equal. If they are not, loosen the jamb nuts and adjust the wires as required so the length of each is equal. 3. Tighten each forward wire until is snug, then tighten the jamb nuts. Wire should not be overly tight, but should be tight enough to prevent excessive motion at the center. 4. Next, tighten the aft wires in a similar fashion; measuring between the face of the clevises and loosening, then tightening the wires until they are of equal. Secure with jamb nuts. BLEEDING BRAKE SYSTEM Whenever the hydraulic brake lines are disconnected and reattached the brake system should be bled. To bleed the brake system: 1. Check that all lines are properly attached between the brake calipers and brake master cylinders 2. Check brake fluid reservoir level and fill to MAX line (located on the pilot side of the engine compartment mounted to the firewall). 3. Depress brakes using pilot pedals, brakes will likely be “spongy” and need significant travel to build braking force. 4. Loosen hydraulic fitting at one brake caliper just enough to let fluid and air seep out when brakes are actuated. 5. While one person actuates the brakes, a second person should watch the brake caliper with the loose fitting. 6. If air is in the system, actuating the brakes will cause bubbles in the fluid coming out of the loosened brake caliper fitting. 7. Actuate the brakes through full travel several times until all the bubbles have been released and fluid is being expelled at the loose caliper without signs of air. 8. Tighten the loose caliper fitting. 9. Check fluid level in brake fluid reservoir and refill to MAX line as necessary. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision F Page 45 of 104 P/N 1005723 Doc. No. W8750-24-01 10. Repeat procedure at each caliper. 11. When complete, brakes should not feel “soft” or “spongy” when actuated. BLEEDING BRAKE SYSTEM (ALT.) When the Hydraulic Brake system is disconnected use the primary procedures listed in the previous section, or as an alternative method to bleed the brake system is cross bleeding between main gear calipers and to brake reservoir (Back Bleeding). To bleed the brakes system using this alternate method: 1. Connect pressurize brake bleeding system to outboard caliper. CAUTION WHEN PERFORMING CROSS BLEEDING, IT MAY BE NECESSARY TO REMOVE RESIDUAL FLUID FROM BRAKE RESEVERIOR TO PREVENT OVERFLOW. 2. Open inboard and outboard bleeders on main gear and pump fluid between calipers till all air has been purged from calipers. 3. Tighten inboard caliper bleeder and continue pressurization to reservoir till all air has been purged from line. 4. Perform steps 1 thru 3 on opposite main gear 5. When complete check brake fluid in reservoir service to max line if necessary. 6. When complete, brakes should not feel “soft” or “spongy” when actuated. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 46 of 104 Revision F FIGURE 4-2: MAIN GEAR, LOWER SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision IR Page 47 of 104 P/N 1005723 Doc. No. W8750-24-01 4.1 MAIN GEAR RETRACTION DESCRIPTION Refer to Figures 4-1, 4-2, 4-3, 4-4A, 4-4B, 4-5 and 4-6 for visual reference. Retraction and extension of the main gear is accomplished with a hydraulic rack and pinion type actuator. The actuator consists of two opposing pistons connected by a geared rack, with a rotating pinion gear in the middle. Hydraulic fluid is transferred from one piston to the other using an electrically reversible hydraulic pump located in the empennage of the aircraft. The differential pressure build up causes the piston to move, pushing the rack and rotating the pinion gear and its attached drive shaft. Attached to each end of the drive shaft are actuating arms that drive separate rod linkages with adjustable rod ends. The drive shaft and actuating arms have a keyway to prevent slippage on the rotating drive shaft. The rod linkages push and pull on the Main Gear Top Arm Assembly causing it to pivot around a fixed point. Also attached to the actuators drive shaft is a visual gear position indicator. This indicator consists of colored bands that rotate with the drive shaft allowing the pilot to visually determine the position of the main landing gear by looking at a placard on the deck of the float. Since the actuator rotates through approximately 193 degrees, the rod linkages and the actuating arm pass an over center point, preventing reverse driving of the rack and pinion actuator in both the fully extended and fully retracted positions. The actuator rotation is adjusted by setscrews that determine the length of travel of the actuator pistons. Providing an over center up-lock prevents inadvertent main gear extension in the case of a hydraulic failure. As a secondary safety to ensure the geometry remains over center with a hydraulic failure, a spring is installed on the actuating arm preventing motion of the rack and pinion actuator. Since the retraction mechanism is over center, the weight of the landing gear and oleo, when retracted, also prevent the retraction mechanism from rotating past the over center point. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 48 of 104 Revision F FIGURE 4-3: MAIN GEAR GREASING POINTS SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 49 of 104 P/N 1005723 Doc. No. W8750-24-01 4.1 MAIN GEAR RETRACTION DESCRIPTION (CONTINUED) In addition to the over center locking provided by the rod linkages and actuator arm for the gear extended position, a second down locking method is provided as well. The geometry of the main gear drag link, oleo-pneumatic shock strut and the top arm assembly, provide an additional over center locking method. The force vector from the oleo, (directed in line with the centerline of the oleo assembly) rotates the contacting face on the top arm assembly into contact with the main gear top mount at all positions of oleo stroke. This transfers the landing load into a structure designed to withstand the generated landing forces, as well as prevents the top arm from rotating and collapsing the main landing gear. There are two proximity switches on each main gear unit. One for sensing gear up position, and the other for gear down position. These are easily replaceable and can essentially be adjusted during maintenance, see figure 4-4A and 4-5. The proximity sensors have a built in LED to indicate when they are sensing the gear position. This feature greatly aids in the setup and servicing of the sensors. There are several service points on the main landing gear to pay attention to during maintenance. Grease zerks are located on the pivots of the main gear draglinks, each wheel axle, top and bottom pivot points on the oleo- pneumatic shock strut, and the rotation point of the top arm assembly, see figure 4-3. The adjustable rod end bearings are permanently sealed and do not require servicing. Inspect the rod ends for freedom of movement and corrosion. Replace the rod ends when necessary. Depending on the operating environment, greasing requirements may vary. Highly corrosive environments, such as salt water, may require more frequent inspections. Regardless, the gear should be inspected visually at least every 25 hours for cleanliness and proper lubrication. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 50 of 104 Revision C FIGURE 4-4A: MAIN GEAR ADJ. DOWN SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 51 of 104 P/N 1005723 Doc. No. W8750-24-01 FIGURE 4-4B: MAIN GEAR ADJ. DOWN INSERT TEST PAPER SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 52 of 104 Revision C FIGURE 4-5: MAIN GEAR ADJ. UP SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 53 of 104 P/N 1005723 Doc. No. W8750-24-01 FIGURE 4-6: MAIN GEAR DOWN STOP ADJ. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 54 of 104 Revision C 4.2 MAIN GEAR ASSEMBLY SETUP AND ADJUSTMENT Put aircraft on jacks to allow free extension and retraction of the landing gear. Use safe operating practices when working around moving hydraulic components. The actuators operate at high pressures and generate high forces when repositioning the landing gear. Adjusting the Gear Down position: (See figure 4-4A and 4-4B) 1. Bleed pressure off the hydraulic lines by moving emergency gear position selector both directions to Up and Down. This will relieve pressure in the lines allowing hydraulic lines to be unhooked without spilling fluid that is under pressure, Item 1. Leave emergency gear position selector in the Up position to allow actuator movement. 2. Remove the AN12 bolt at the top of the oleo shock strut attaching it to the top arm assembly, Item 1. This will allow the retraction mechanism to be repositioned by hand without having to move the weight of the tires, oleo and drag link assembly. Place a rag between the drag link and the bulkhead as the gear will rotate and make contact with bulkhead, possibly scratching the finish. 3. Remove the 4 nuts connecting the rod linkages (Item 3) to the actuator arms (Item 5). Remove the rod linkages from the arms. (Note: There are qty. 2 NAS1149F0463P washers between the rod end and the actuator arm.) 4. Remove the spring attached to the actuator arm. NOTE: Steps 5 through 16 are for re-rigging the actuator. If no changes are done to actuator, skip to step 17. 5. Loosen the AN4 bolt and nut holding the actuator arms (Item 5) to the actuator shaft. Remove the two arms from the shaft being careful not to lose the parallel keys. It is not necessary to remove the visual gear position indicator assembly from the outboard actuator arm. 6. Remove the qty. 4, 5/16-18 bolts, that hold the actuator into the channel that runs across the top of the wheel well. 7. Allow the actuator to drop down from channel and remove the up and down hydraulic lines. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 55 of 104 P/N 1005723 Doc. No. W8750-24-01 4.2 MAIN GEAR ASSEMBLY SETUP AND ADJUSTMENT (CONT.) 8. NOTE: The actuator should not need adjustment while in service. The only time adjustment should be necessary is when the actuator is disassembled in order to replace internal seals. Assuming this has been done the remaining steps are for re-rigging the actuator to be installed back in the float. 9. With the actuator assembled and removed from float, attach Wipaire Tool 1004800 to the actuator, taking note that the FORWARD arrow is pointing forward on the actuator. Use the 5/16-18 bolts to attach the tool to the actuator. 10. Rotate the actuator shaft fully to the DOWN position. If the two keyway slots do not line up when the actuators internal piston contacts the “DOWN” adjustment set screw (Item 8), the actuator needs adjustment. It may be necessary to use one of the actuator arms removed in step 5 to help rotate the actuator. 11. To adjust the “DOWN” position, loosen the “DOWN” adjustment screw jamb nut (Item 9) and back off the adjustment screw. 12. Align the keyway on the actuator shaft (Item 4) with the keyway on Wipaire Tool 1004800. Insert the parallel key removed in step 5 into the aligned keyways. 13. Thread in the Down Adjustment setscrew until light contact is made between the setscrew and the actuators internal piston. Do not over tighten as the actuator cannot rotate with Wipaire Tool 1004800 and the key installed. Over tightening can damage the face of the actuator piston. 14. With setscrew positioned against the piston face, tighten the adjustment screw jamb nut (Item 9). 15. Repeat steps 10 - 14 for setting the UP position setscrew. (See figure 4-5) 16. Install actuator in float by reversing steps thru 7. Safety wire 5/16-18 bolts when installed. Outer face of actuator arms should be flush to actuator shaft. It is recommended to leave the spring disconnected during gear rigging. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 56 of 104 Revision C 4.2 MAIN GEAR ASSEMBLY SETUP AND ADJUSTMENT (CONT.) 17. Reattach rod linkages to actuator arms. Loosen the rod linkage jamb nuts and lengthen the rods slightly (Item 3). Make equal adjustments to each rod. 18. Rotate actuator arms until the internal piston is against the Down Adjustment Screw. 19. Shorten the Rod Linkage until the Top Arm Contact Face (Item 15) touches the contact face of the Top Mount (Item 7). Make equal adjustments to each rod. Actuator needs to be rotated fully against the Down Adjustment Screw. 20. Visually inspect the Rod Linkage position (Item 3) versus the actuator shaft (Item 4). When rigged correctly, the bottom edge of the rod linkage should pass through the shaft as shown in Figure 4-4A. 21. Ensure gear is in down and locked position. 22. Using a small digital protractor, the over- center angle will be verified. Lay the protractor across the bottom of the lower two screw holes in the actuator arm. Note: Older float models may not have flat spot shown; use the same location as shown. Zero the protractor. See Figure 4-4B. Then place the protractor on the top or bottom of the rod linkage. The measured angle should be 4° ± 1°. Repeat for the other actuator arm and rod linkage by zeroing the protractor on the other actuator arm and measuring the rod linkage angle. 23. If angle is lower than required, the down Adjustment Screw (Item 8) should be turned out to allow more rotation. If the angle is greater than required, the actuator is over- rotating and the adjustment screw should be turned in. One turn of the adjustment screw changes the angle by approximately 2°. 24. If adjustments have been made to the Down Adjustment Screw, the Rod Linkage (Item 3) may need to be shortened or lengthened so that the Top Arm Contact Face (Item 15) still makes contact with the Top Mount. 25. Repeat steps 22 through 24 until angles measure within tolerance. 26. With setscrew positioned against the piston face, tighten the adjustment screw jam nut (Item 9). SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 57 of 104 P/N 1005723 Doc. No. W8750-24-01 4.2 MAIN GEAR ASSEMBLY SETUP AND ADJUSTMENT (CONT.) 27. Preload the rod linkages by shortening each rod by 1/2 turn after the contact faces touch on the Top Arm and Top Mount. Tighten the Rod Linkage jamb nuts. 28. Check the operation of the over center down lock. As the actuator rotates causing the contact faces to touch, the actuator arm should continue to rotate and “snap” past Top Dead Center (TDC). Make sure that there is preload on the linkage rods so that contact faces remain touching past TDC. Push and pull on the Top Arm Assembly (Item 2) to ensure it is locked over center. The Top Arm Assembly needs to be contacting the Top Mount (Item 7) when the gear is extended to properly transfer the landing loads. Ensure Top Arm and Top Mount are making contact by sliding a 3- inch wide piece of paper in (See Figure 4-4B and photo on this page), then moving gear to down and locked position. If paper is tight, gear is rigged correctly. If paper is able to slide out, then the Top Arm and Top Mount are not making proper contact and need further adjustment. 29. Reattach spring. 30. Loosen the (Fig 4-6, Item 1) jam nut on the Main Gear Down Stop Assembly, and screw in the NAS-428 adjustment bolt (Fig 4-6, Item 2). Verify the bolt does not touch the Top Arm when gear is in the down position. When the aircraft is off the jack stands and the weight of the aircraft fully on the SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 58 of 104 Revision C wheels, adjust the NAS-428 bolt to lightly make contact with the Main Gear Top Arm when the gear is in the full down position, then turn the bolt one and a half turns in so that the bolt no longer makes contact with the Top Arm. Gap should be about 0.050 inches. Tighten the jam nut. NOTE: There are three “over center” locks on the main gear when the gear is down. The first is the over center rod linkages that are adjusted in the above steps. The second is from the spring pulling on the actuator arm when the gear is in the down position. The spring prevents the actuator from moving in the event of a loss of hydraulic pressure. The third comes in the form of the angle between the oleo-pneumatic shock strut and the Top Arm Assembly. The vector of the oleo force is “over center”, about at the rotation point on the Top Arm Assembly. Thus, one could effectively remove the entire gear actuator, and the geometry of the Oleo and the Top Arm alone would force the contact faces of the top arm and top mount together and lock it “over center.” There are also two “over center” locks when the gear is in the retracted “UP” position. The first is a spring installed on the actuating arm that prevents motion of the rack and pinion actuator in the event of a hydraulic failure. The second over center lock comes from the geometry of the gear in the up position. Since the retraction mechanism is driven over center, the weight of the landing gear and oleo, when retracted, prevent the retraction mechanism from rotating past the over center point. The weight of the gear wants to rotate the Top Arm Assembly, however, when rotating the Top Arm, the rod linkages must also move. The geometry is such that the rod linkages are “over center” on the actuator shaft centerline, and thus the rod linkages are trying to rotate the actuator more toward the “UP” position and in turn force the actuator piston face into the up adjustment setscrew. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 59 of 104 P/N 1005723 Doc. No. W8750-24-01 4.3 ADJUSTING THE GEAR UP POSITION 1. DO NOT adjust the rod linkages (Item 3) when setting the over center up adjustment. 2. Rotate the actuator rotation arm fully toward the gear up position. 3. When the actuators internal piston contacts the “UP” adjustment setscrew, check to make sure all the linkages have rotated past Top Dead Center (TDC) by pushing and pulling on the Top Arm Assembly. The “UP” adjustment screw (Item 10) should not need to be adjusted if properly set using Wipaire Tool 1004800 during the actuator maintenance. (If it is found that one can reverse drive the rotary actuator and pull the gear down by hand, the rod linkage and the actuator arms have not moved past TDC. Re-check the position of the “UP” stop using Wipaire Tool 1004800. If the “UP” position is found to be correct, look for signs of damage in the floats as something is out of position preventing the stop setting using Tool 1004800 from being correct. Call Wipaire’s Customer Service Department for specific instructions. 4. Bleed air from hydraulic system by actuating the gear several times with the electric hydraulic pumps. See Chapter 5, Section 5.1, for specific bleeding instructions. 5. If it is necessary to adjust gear up and down position switches proceed to next section. If not, lower gear and reattach oleo shock strut to top arm assembly. When aircraft weight is fully on the wheels, remember to set the NAS-428 bolt on the Main Gear Down Stop Assembly (refer to Section 4.2 Step 30). SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 60 of 104 Revision C 4.4 ADJUST MAIN UP AND DOWN POSITION SWITCHES 1. With the aircraft still on jacks, position the gear in the “UP” position. This allows access to the gear down proximity switch. 2. Loosen the jam nut on the Gear Down Proximity Switch located on the back of the Main Gear Top Mount. Thread the Gear Down Proximity Switch in or out until the face of the sensor is flush with the face of the Main Gear Top Mount. Reference Figure 4-4B. Tighten the jam nut on the proximity switch to 10 +/- 3 inch-pounds. 3. Thread out the Set Screw Adjustment (Item 6), located on the Top Arm Assembly (Item 2). 4. Position the gear in the “DOWN” position. With the aircraft master switch on, thus providing power to the proximity switch, thread the Set Screw Adjustment (located on the Top Arm Assembly) in until the LED light built into the proximity switch initially illuminates with the gear arm in the full down over center locked position, then thread the set screw in an additional half turn. 5. Reposition the gear to the “UP” position. 6. Loosen the jam nuts on the gear up proximity sensor. 7. Adjust the gear up proximity sensor switch to have between a 0.030 - 0.060” gap between the proximity sensor plate and the proximity sensor. Tighten the jam nuts on the proximity sensor to 10 +/- 3 inch- pounds. 8. At this point, check to insure that the built in LED on the proximity sensor is illuminated when the sensor plate is rotated in front of the sensor. 9. With the gear in the full up position, loosen the AN6 bolt holding the proximity sensor plate to the Main Gear Top Arm and the socket head cap screw that prevents rotation of the sensor plate. 10. Rotate the sensor plate so that the sensor is near the edge of the plate with the gear in the up position. Reference Figure 4-5 inset. 11. Tighten the AN6 bolt, socket head cap screw, and re-safety AN6 bolt. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 61 of 104 P/N 1005723 Doc. No. W8750-24-01 12. Check for proper light illumination on the gear selector in the cockpit in both the up and down position. 13. If necessary, reattach the oleo shock strut to the Top Arm Assembly. 14. Remove aircraft from jack stands SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 62 of 104 Revision C FIGURE 4-7: ROTARY ACTUATOR SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 63 of 104 P/N 1005723 Doc. No. W8750-24-01 FIGURE 4-8: MAIN SHOCK STRUT SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 64 of 104 Revision C 4.5 EMERGENCY GEAR OPERATION An emergency hand pump is provided in case of total electric pump failure or loss of fluid. The emergency hand pump draws hydraulic fluid from the bottom of the hydraulic power pack reservoir. The hydraulic power pack electric pumps have fluid pickup tubes that do not reach the bottom of the hydraulic fluid reservoir. This prevents the electric pump from being able to pump all the fluid out of the system. The remaining small reserve quantity of fluid below the electric pump pickup tube is then reserved exclusively for the emergency hand pump. The quantity of reserve fluid below the electric pump pickup tubes is sufficient to raise or lower the landing gear with the hand pump alone. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 65 of 104 P/N 1005723 Doc. No. W8750-24-01 CHAPTER 5 HYDRAULICS SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 66 of 104 Revision C 5.0 HYDRAULIC SYSTEM WET HANDLE VS. DRY HANDLE SYSTEM These instructions are for the later model “dry handle” hydraulic system that is used for new 8750 float installations. For legacy installations retrofitted from 8000’s to 8750s, the “wet handle” pump system may be installed. The dry handle system is characterized by a gear selector head containing an electrical switch that is connected with wires to the aft fuselage mounted pump. The pump direction is reversible. The legacy wet handle system is characterized by a gear selector head that contains a mechanical valve and is connected with hydraulic lines directly to the gear. The pump direction is not reversible. For retrofit installations, where the model 8750 is mated to the wet handle equipped aircraft, operation of the hydraulic system is the same as with the model 8000 installation – pressure and return lines at the fuselage exits are connected to pressure and return lines at the strut (pylon) attach points. The only electrical difference between the standard and retrofit hydraulic system is the addition of a port and starboard (low) power wire that runs to the powered proximity switch that commands main gear position indication. See drawing number 1006012, revision A, or later approved revision, for electrical information pertaining to the hydraulic system. See drawing number 1006004, latest revision for hydraulic system descriptive information for the retrofit installation. For Cessna 208 see drawing number 1006005, revision A or later approved revision, or for Cessna 208B see drawing number 1006016 revision A or later approved for hydraulic system descriptive information for the current production installation. From the aircraft belly – up the hydraulic system should be maintained with ICA document number 1002554, revision G or later approved revision, as applicable to the model 8000 installation. From the aircraft belly – down, the hydraulic system shall be maintained with these ICA SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision D Page 67 of 104 P/N 1005723 Doc. No. W8750-24-01 The following instructions pertain to the current production dry-handle system configuration with reversible pumps. BASIC DESCRIPTION A pressure of between 500 psi and 700 psi in the “DOWN” position and 500 psi and 1200 psi in the “UP” position is maintained in the supply line. When the pressure falls below 500 psi in the “UP” and “DOWN” position, the pressure switch activates the pump solenoid, providing power to the pump. When the pressure reaches 700 psi in the “DOWN” position and 1200 in the “UP” position, the pressure switch deactivates the solenoid and the pump motor stops. A check valve on the output side of the pump retains pressure in the system while the pump is off. The pump has an interval relief valve that directs fluid back to the un-pressurized pump reservoirs when the line pressure exceeds 1400 psi. The system also has an internal relief valve to protect against thermal expansion when line pressure exceeds 1900 psi. A timer circuit is included on the powerpack that commands pump operation briefly regardless of pressure switch position when a new gear position is selected; this allows the gear system to avoid potential thermal lock caused by fluid expansion during flight or on the ground. “POWERPACK” PUMP ASSEMBLY, IN AFT FUSELAGE SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 68 of 104 Revision C FIGURE 5-1: HYDRAULIC SCHEMATIC HYDRAULIC RAMS LOCATED IN FLOATS UNION FITTINGS FOR WHEEL/FLOAT SWAP DUAL DIRECTION PUMP INTERNAL SHUTTLE VALVE WITH 1150 RELIEF +/- 150 PSI 1400 PSI THERMAL RELIEF UP AND DOWN PREASURE SWITCHES FOR EACH PUMP UP 500-1000 PSI DOWN 500-700 PSI AFT FUSELAGE MOUNTED POWER PACK WITH PUMPS, PREASURE SWITHCES AND CHECK VALVES. CROSS FITTINGS LOWER FUSELAGE EMERGENCY HAND PUMP IN CABIN A RET DN NOSE GEAR RAMS W/POSITION SWITCHES UP DOWN UP DOWN DOWN UP DOWN UP MAIN GEAR RAMS W/PROXIMITY SWITCHES RET UP DN UP RET S B SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 69 of 104 P/N 1005723 Doc. No. W8750-24-01 5.1 BLEEDING THE HYDRAULIC SYSTEM The system automatically bleeds, provided sufficient oil is maintained in the reservoir. To check the fluid level, fill the reservoir through the servicing point on the power pack assembly with MIL-H-5606 hydraulic oil and cycle the gear. If the reservoir empties, stop the cycle by pulling the pump motor circuit breakers. Fill the reservoir again and complete the cycle. Continue this procedure until the fluid level in the reservoir stabilizes (it will vary in level between gear up and down positions). If the fluid level continues to decline during gear cycles, check for external leaks. When the fluid level stabilizes, fill the reservoir to the normal operating range as placarded on the pump reservoir. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 70 of 104 Revision C THIS PAGE INTENTIONALLY LEFT BLANK SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 71 of 104 P/N 1005723 Doc. No. W8750-24-01 CHAPTER 6 WATER RUDDER SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 72 of 104 Revision C 6.0 BASIC DESCRIPTION Water rudder retract and hand pump, mounted to cockpit floor The water rudder-retract system is manually operated by a lever through a system of cables and pulleys. A lever in the cockpit controls the position of the rudders. The lever has a locking feature that prevents inadvertent operation of the rudders in flight. Steering is directed from the aircraft rudder steering system. The controls are interconnected and seamless to the operator. The water rudder moves with the air rudder. WATER RUDDER RIGGING All cables in the water rudder steering system should be rigged to 30 +/- 5 lbs. Retraction cables should be rigged such that the top of the rudder blade is approx. 1 inch from the rudder stop on the rudder post in the up position and that the cables are just slack in the down position. Water rudders should be centered, when the air rudder is centered, by adjusting turnbuckles. There is no left or right rigging adjustment related to the maximum travel of the water rudder system. For 208 cable routing see figure 6-2 or installation drawing 1006006, revision A or later approved revision. For 208B cable routing see figure 6-3 or installation drawing number 1006015 Rev A or later approved. Water rudder retract handle with lock – pull finger lock to move handle. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 73 of 104 P/N 1005723 Doc. No. W8750-24-01 SEE INSTALL DRAWING # 1006006 REV A OR LATER APPROVED REVISION FIGURE 6-2: WATER RUDDER/STEERING CABLE ROUTING, MODEL 208 SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 74 of 104 Revision C SEE INSTALL DRAWING # 1006015 REV A OR LATER APPROVED REVISION FIGURE 6-3: WATER RUDDER/STEERING CABLE ROUTING, MODEL 208B SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 75 of 104 P/N 1005723 Doc. No. W8750-24-01 CHAPTER 7 ELECTRICAL SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 76 of 104 Revision C 7.0 ELECTRICAL SYSTEM WET HANDLE VS. DRY HANDLE SYSTEM These instructions are for the later model (current production) “dry handle” electrical system that is used for new 8750 float installations. For legacy installations retrofitted from 8000’s to 8750s, the “wet handle” system may be installed. The dry handle system is characterized by a gear selector head containing an electrical switch connected with wires to the aft fuselage mounted pump. The pump direction is reversible. The direction the pump turns is controlled by the gear position switch. The legacy wet handle system is characterized by a gear selector head that contains a mechanical hydraulic valve and is connected with hydraulic lines directly to the gear. The pump direction is not reversible. For retrofit installations, where the model 8750 is mated to the wet handle equipped aircraft, operation of the hydraulic system is the same as with the model 8000 installation – pressure and return lines at the fuselage exits are connected to pressure and return lines at the strut (pylon) attach points. The only electrical difference between the legacy 8000 and retrofit 8750 system is the addition of a port and starboard (low) power wire that runs to the powered proximity switch that commands main gear position indication. For Cessna 208 see drawing number 1006012, revision A, or later approved revision, for electrical information pertaining to the retrofit. For Cessna 208/208B see drawing number 1006011, revision A, or later approved revision, for electrical system descriptive information for the current production dry handle reversible pump installation. For Cessna 208 wet handle installation, the pump/handle electrical system should be maintained with the ICA pertaining to the model 8000 installation, document P/N 1002554, revision G or later approved revision, with consideration for the two additional power wires shown in drawing 1006012, revision A or later approved revision. For Cessna 208/208B dry handle installation, the pump/handle electrical systems should be maintained with these ICA. The dry handle SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 77 of 104 P/N 1005723 Doc. No. W8750-24-01 system is installed standard for all new 8750 installations starting May, 2012. BASIC DESCRIPTION The following electrical systems are added with the installation of Wipline 8750 floats on the Cessna 208/208B: 1. 24V DC Hydraulic pumps (2), each pump with its own dedicated circuit breaker 2. Gear selector head, for changing pump flow directions to actuate the landing gear up and down, and indicate gear position For detailed schematic information regarding the electrical system, refer to the previously listed Wipaire, Inc. wiring diagrams. ELECTRIC HYDRAULIC PUMPS The installed 24V DC electrically reversing hydraulic pumps are wired independently to allow failure of one pump without affecting the other pump. The pump is electrically shut-off in the up and down directions by a fluid pressure switch that cuts pump power when sufficient hydraulic pressure is obtained in the gear system. Gear swings should take less than 45 seconds with both pumps operating. If the gear cycle time is greater than 45 seconds it is likely that one pump is not pumping efficiently and/or not operating correctly. This can be verified by pulling each pump breaker to see if the system functions on one pump, but not the other. GEAR SELECTOR HEAD The installed gear selector head is similar to units used in several other models of Wipline floats. This selector head switches current directions to the electric pumps, reversing their pumping direction. It also indicates gear positions using four blue and four green incandescent lights. The lights for the nose gear are turned on with a magnetic switch that senses a magnet in the hydraulic cylinder piston. The lights for the main gear position are triggered by inductive proximity switches that are triggered by metal flags on the main gear arm. Lights are a cartridge style and can be replaced by pulling them out from the bezel. A suspected defective light can be quickly replaced with an adjacent light for troubleshooting a suspected defective bulb. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 78 of 104 Revision C THIS PAGE INTENTIONALLY LEFT BLANK SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 79 of 104 P/N 1005723 Doc. No. W8750-24-01 CHAPTER 8 TKS SYSEM EQUIPPED AIRCRAFT REQUIREMENTS SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 80 of 104 Revision C 8.0 TKS SYSTEM BASIC DESCRIPTION The TKS ice protection system is a system that releases glycol based fluid through laser-drilled panels on the leading edges of the wings, horizontal, vertical stabilizers and other components to prevent ice accumulation. A slinger ring on the propeller also emits fluid to keep the prop, windshield, cargo pod and landing gear free of ice. TKS SYTEM MODIFICATION WHEN FLOATS INSTALLED For requirements and guidance on modifying the TKS Icing System on Cessna 208/208B Caravan when 8750 series floats are installed refer to Wipaire installation drawing 1004806 revision A, or later approved revision. – The TKS fluid pod must be removed and connections capped and covered. For additional control surface movement changes see Wipaire installation drawing 6C1-2023. Control throws are different for the floatplane and TKS equipped landplane. The TKS system is disabled when the floats are installed. CAUTION THE CESSNA 208/208B WITH MODEL 8750 FLOATS IS NOT APPROVED FOR FLIGHT IN KNOWN ICING CONDITIONS. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 81 of 104 P/N 1005723 Doc. No. W8750-24-01 CHAPTER 9 RECOMMENDED PROCESSES, PRODUCTS AND INSP. CHECKLISTS SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 82 of 104 Revision F 9.0 SERVICING INSTRUCTIONS As coded in the Inspection Time Limits chart in this section, there are items to be checked each 25, 50, 100, and 200 hours. Also, there are notes on special items which may require servicing at more frequent intervals. * When conducting an inspection at 25 hours, all items marked for 25 hours would be accomplished. * at 50 hours, the 25 and 50-hour items would be accomplished. *at 100 hours, the 25, 50, and 100-hour items would be accomplished. * at 200 hours, the 25, 50, 100 and 200-hour items would be accomplished. * A complete inspection (Annual Inspection) would include all 25, 50, 100, 200 hour items. Below is a list of recommended lubricants and “protection” products when servicing float hull and other amphibious components. This lists products used by Wipaire during assembly of the floats. There may be equivalent products just as satisfactory for protection. However, it is recommended if trying different products, to inspect them frequently so as to determine their effectiveness. Protection of nuts, bolts, hydraulic lines, metal surfaces, or electrical connections. Dinitrol AV30 Dinol Group General Lubricants LPS 1, LPS 2 and LPS 3 LPS Industries CRC – SP400 Soft Seal CRC Industries Oil Bath Wheel System Aeroshell Multigrade W 15 W 50 Oil Shell Global Solutions* *For main gear assemblies including the oil bath wheel system, any standard engine oil is acceptable. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision E Page 83 of 104 P/N 1005723 Doc. No. W8750-24-01 Wheel Bearings, Main Gear Retract Mechanism, Nose Gear Pivot and Rod Ends *HCF Grease, P/N 605 HCF Industries *Aeroshell 22 Shell Global Solutions *Green Grease, Multi-Purpose Green Grease Inc. *Aviation Grease SHC 100 ExxonMobil Aviation Lubricants * If existing grease cannot be identified you must lubri-flush all float grease fittings until visibly exhausting all old grease and new grease is coming out. Additionally if you cannot determine existing grease in wheel bearings, completely clean and repack bearings with new grease. Metal Corrosion Protection Boeshield T9 Rust Protection Boeing Company Corrosion X ACF-50 Rust Protection Tef-Gel Ultra Safety Systems, Inc. Float Sealant 890 B2 or B4 Pro Seal Company PR 1440 C PPG Aerospace RTV Silicones General Electric SIKAFLEX 201 or 252 Sika Manufacturing Teflon Spray 6P-730A Comet Industries Hydraulic Fluid Mil-H-5606 Electrical Insulating Compound *Dow Corning 4 (DC4) Dow Corning Corporation Bolt Torque Bolts in Critical Areas - For common, correct torque when installed, or when visual inspection indicates a need for a torque check. **Tension Nut Nut-Bolt Size Torque Limits (in-lbs) Min. Max. 8-36 12 15 10-32 20 25 1/4-28 50 70 5/16-24 100 140 3/8-24 160 190 7/16-20 450 500 1/2-20 480 690 9/16-18 800 1,000 5/8-18 1,100 1,300 3/4-16 2,300 2,500 7/8-14 2,500 3,000 1-14 3,700 4,500 1 1/8-12 5,000 7,000 1 1/4-12 9,000 11,000 **Shear Nut Nut-Bolt Size Torque Limits (in-lbs) Min. Max. 8-36 7 9 10-32 12 15 1/4-28 30 40 5/16-24 60 85 3/8-24 95 110 7/16-20 270 300 1/2-20 290 410 9/16-18 480 600 5/8-18 600 780 3/4-16 1,300 1,500 7/8-14 1,500 1,800 1-14 2,200 3,300 1 1/8-12 3,000 4,200 1 1/4-12 5,400 6,600 ** A Torque of 80% should be used when Tef-Gel is applied to the bolt. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 84 of 104 Revision C 9.1 CORROSION REMOVAL Corrosion is usually detected visually, which is why Wipaire strongly recommends the previous cleaning and inspection procedures. It can appear as a white or pale green powder, discoloration of the metal surface, or bubbles and blisters under the surface of the paint. Light corrosion is removed by gentle sanding or chromic acid. Moderate and severe corrosion (blistering, flaking and pitting) can be removed by heavier sanding or grinding. Reinforcement or replacement of affected areas may be necessary if there is critical loss of strength in parent metal and depends on location and other factors. Pylon before repair… Pylon Fully Repaired After removing the corrosion, restore the area to the original finish, like prime and enamel, or coat the metal with a waterproof grease. CORROSION X, or equivalent, should also be applied to stop corrosion and repel moisture and contaminants. Corrosion Limits Area Allowable Thickness loss Bottom skins 30% Side Skins fwd of Step 30% Side Skins aft of Step 20% Top Deck 30% Machining 0.015” Struts 0.030” NOTES: 1. Maximum surface area for skin corrosion, up to to the maximum depth, shall not exceed one (1) square inch and must be separated by at least 14 inches from any other skin corrosion damage. 2. For machined fittings, struts, and pylons, corrosion limits are provided as maximum pitting depths. Corroded surface area for these limits shall not exceed 0.5 square inches, and must be separated by at least 5 inches from any other corrosion damage FIGURE 8-1: CORROSION LIMITS SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 85 of 104 P/N 1005723 Doc. No. W8750-24-01 9.2 MAINTENANCE CHECKLIST SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 86 of 104 Revision C INSP MECHANIC Lt. Rt. HOURLY LIMITS Annual X X X X X X X X X X X 200 X 100 X X X X X X 50 X 25 X or more often INSTRUCTIONS / PROCEDURES Details If the airplane is exposed to salt or polluted water, the chance for corrosion increases dramatically. Daily basic cleaning is essential. Float exterior – inspect for damage, wrinkled metal, corrosion, paint loss, etc. If the floats are installed, remove the center section fairings for access. Strut and attach fittings: clean upper attach fittings and dog bone saddle area, If off aircraft, re-grease bolts and return. Boarding steps disassemble as needed and grease the step-slide tubes. Remove forward and aft pylon fairings and open rope access door. Inspect door for security. Inspect overall inboard and outboard skins and fairings for damage or corrosion. Inspect pylon and drag brace structure for corrosion or deformation. Inspect all attaching hardware for security, damage, and corrosion. Apply ACF 50 to Pylon Float Deck attach point hardware prior to reinstallation. Spreader Bars: inspect for loose screws and cracks. On the aircraft and floats: re-coat exposed hardware with suitable coating for corrosion per section 9.0 Servicing Instructions of this manual. Closely inspect for wrinkled metal & cracked flanges. After inspection, coat latch mechanism with suitable anti-corrosion grease to protect per section 9.0 Servicing Instructions of this manual. General Wash aircraft and floats with fresh water and inspect surfaces, hardware and strut connections for corrosion. Check installed placards against the AFM/POH Supplement Section 2, and installation drawings. Float Installation: Pylon, Inspect pylon structure and attachment to float and aircraft. Disassemble and grease the flying wire clevis bolts/pins. Float Structure (Interior): Baggage compartment covers and seals: inspect for condition, security, operation, excessive wear, and corrosion under nut- plates. Pumper Tube Installation: inspect for condition, security, and routing of hoses. General Hulls & Struts Float Interior SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision C Page 87 of 104 P/N 1005723 Doc. No. W8750-24-01 INSP MECHANIC Lt. Rt. HOURLY LIMITS Annual X X X X X X X X 200 X 100 X X X 50 X 25 X X INSTRUCTIONS / PROCEDURES Details Water rudder blades and posts – inspect for damage, security of attachment, corrosion, paint, rigging. Check post bolts and bushings and lube with LPS 2. Check top and bottom rollers for rotation and lube with LPS 2 or similar product. Tension cables 30 lbs. +/- 5lbs. All hardware should be coated with suitable corrosion prevention compound per section 9.0 Servicing Instructions of this manual. Nose tracks and blocks – clean and dry or clean and wipe with silicone spray. Check side play – 3/32” to 1/8” max tolerance. General Water rudder blades – inspect condition. Water rudder steering and retract systems – inspect the following: cables for broken wire; fittings for cable slippage, cracks and distortion; cable pulleys for freedom of rotation and cable guard pins for presence; rigging. Remove, clean, inspect, and grease the Aux. finlets on the horizontal stabilizer. Pump and indicator light wiring – inspect for chafing, broken, or loose terminals and general condition. Pressure Switches – inspect wiring, mounting, and general condition Pump Motors – inspect wiring, mounting, and general condition. Inspection and servicing nose gear tracks: Nose Gear Box/Block Tracks measured at slide route for wear. .050” or less wear tolerance. Water Rudder System & Tail Electrical System Landing Gear Systems SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 88 of 104 Revision C INSP MECHANIC Lt. Rt. HOURLY LIMITS Annual X X X X X X X X X X X X X X 200 X X 100 X X X X X 50 X X 25 X X X X INSTRUCTIONS / PROCEDURES Details Check fluid level indication on tanks; Fill as needed Main Wheels: 60 psi +/- 5 psi. Nose Wheels: 60 psi +/- 5 psi. When the plastic reservoir is removed, the visible screens should be inspected and cleaned before reassembly. General Nose gear pivot blocks and forks – inspect for condition, lubrication, corrosion, and paint. Nose & Main wheel bearings – Grease Zerks. Inspect Hydraulic rotary actuator in the main wheel well. Hydraulic fluid level : MIL -H-5606 Wheels and tires – inspect for wear, pressure, and condition. Brake assemblies – inspect for wear, corrosion, and leakage. Hydraulic fluid in reservoir should be checked for moisture or other contaminates and changed if necessary. Main and Nose gear actuators, Assemblies – inspect for condition, lubrication, leakage, corrosion, and cleanliness. Nose gear springs – scotch ply springs, inspect for cracks, delamination and paint. Main gear drag link bushings – inspect for condition, lubrication, and corrosion. Clean the wheel wells to facilitate general condition inspection. Main gear oleos – inspect for evidence of leakage, proper extension, and check cylinder for corrosion, pitting, cleanliness, and security. Hydraulic lines and fittings – inspect for leaks, condition, and security. Brake system plumbing – inspect for leakage, condition, and security. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision F Page 89 of 104 P/N 1005723 Doc. No. W8750-24-01 INSP MECHANIC Lt. Rt. HOURLY LIMITS Annual X X X X X 200 X X 100 X X 50 25 INSTRUCTIONS / PROCEDURES Details If full servicing is required, use 5606 hydraulic fluid & Nitrogen Cylinder. Cylinder PSI 400-450 Cylinder Capacity 975 +/- 20mL Inspect main gear up and down linkage for proper engagement. Inspect nose gear trolley for proper travel. Inspect nose gear for excessive play in the down position. Re-grease bearings with suitable water resistant grease per section 9.0 servicing Instructions of this manual. Check oil level and take sample of oil from axle. Inspect per main wheel and tire removal and inspection section of this manual, located in section 4.0 General Main gear oleos – Check for static compression, leaks and proper pressure. The oleo should be fully serviced, replaced, or overhauled as required at annual inspection. Perform retraction tests as follows: 1. Hoist aircraft and place on stands. 2. Turn on Aircraft Master switch. 3. Select Gear ‘UP’ position using selector. 4. Verify gear lights indicate gear positions correctly while gear is in transit and at the end of travel. 5. Select Gear ‘DOWN’ position using selector. 6. Verify gear lights indicate gear positions correctly while gear is in transit and at the end of travel. Perform Emergency Gear Retractions/Extension tests as follows: 1. Pull gear pump circuit breakers (2) 2. Select desired gear position using Emergency Selector Valve. 3. Extend emergency hand pump handle and pump vertically until force increases noticeably (150+ strokes). 4. Verify gear lights indicate gear positions correctly while gear is in transit and at the end of travel. 5. Repeat in opposite direction. Nose and Main wheel bearings – disassemble and inspect (nose wheel only if main gear oil bath system is installed) Main gear with oil bath wheel system installed SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 90 of 104 Revision C 9.3 FLOAT REMOVAL AND RE-INSTALLATION GUIDE SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision F Page 91 of 104 P/N 1005723 Doc. No. W8750-24-01 INSP. MECHANIC Lt. Rt. FLOAT REMOVAL INSTRUCTIONS / PROCEDURES THIS IS INTENDED AS A GENERAL GUIDE. EACH INSTALLATION MAY HAVE SUBTLE DIFFERENCES. ALWAYS USE THE INSTALLATION DRAWINGS AS THE FINAL REFERENCE. ALL WORK SHOULD BE DONE BY CERTIFIED AIRCRAFT TECHNICIANS. 1. Connect the lifting bar to the hoist and position aircraft underneath 2. Remove wing gap strips 3. Inspect aircraft lifting rings for proper assembly and installation before connecting the lifting bar to the aircraft 4. Attach ropes and ballast to tie-down rings as required to keep aircraft level while lifting 5. Lower aircraft so wheels just touch and relieve hydraulic pressure before Pulling pump circuit breakers. Install tie-wrap to shank for safety 6. Remove the following items from aircraft : Nose gear cover plate. Lower nose cowlings. Steering bungee from nose gear attach point. Front flying wire fitting. Strut fairings and belly plate. Tail hatch cover & tail cone (if needed). Rear cargo struts and step assembly. Auxiliary fins (cover holes with cover plates) Nuts from top bolts in forward struts. Bolts from front step struts. Cotter pins from pulley brackets under cargo door. Aft cabin bulkhead and cabin seats as required. Floor cover plates for access to steering cables. Fairleads from under the cabin floor. Elevator down-spring and cable. Hydraulic lines at the Main Gear Box location and cap. Re-mark Airspeed Indicator as needed per print SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 92 of 104 Revision C INSP. MECHANIC Lt. Rt. FLOAT REMOVAL INSTRUCTIONS/PROCEDURES (CONT.) THIS IS INTENDED AS A GENERAL GUIDE. EACH INSTALLATION MAY HAVE SUBTLE DIFFERENCES. ALWAYS USE THE INSTALLATION DRAWINGS AS THE FINAL REFERENCE. ALL WORK SHOULD BE DONE BY CERTIFIED AIRCRAFT TECHNICIANS. (Remove the following items from aircraft continued) Retract cable (Secure in main gear well). Break lines and cap. Electrical cannon plug in main wheel well. Steering cables in tail. Remove rudder horn or clamp to main rudder cables. 7. Assemble main gear if needed. 8. Install nose gear and attach steering bungee. 9. Assemble support crew, minimum six (6) crew members. 10. With wheels just touching the ground, remove the 4 main gear saddles and upper front attach bolts. 11. Lift aircraft and remove floats. 12. Lower aircraft positioning main gear assembly for installation. 13. Torque main gear saddle bolts to 75 ft. lbs. 14. Connect brake lines and bleed for air bubbles. 15. Install main gear belly plate and fairings. 16. Remove front strut fittings. 17. Install pilot and co-pilot step assemblies. 18. Replace Passenger Door Cable Assy. (2) P/N S2837-2 with original Cable Assy. (2) P/N S2837-1 19. Install tail cone and tail hatch cover. 20. Install lower LT. cowling. 21. Install all nose gear fittings. 22. Install all floor plates and carpet. 23. Install aft bulkhead. 24. Install any seats previously removed. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision F Page 93 of 104 P/N 1005723 Doc. No. W8750-24-01 INSP. NOTES: MECHANIC Lt. Rt. FLOAT REMOVAL INSTRUCTIONS/PROCEDURES (CONT.) THIS IS INTENDED AS A GENERAL GUIDE. EACH INSTALLATION MAY HAVE SUBTLE DIFFERENCES. ALWAYS USE THE INSTALLATION DRAWINGS AS THE FINAL REFERENCE. ALL WORK SHOULD BE DONE BY CERTIFIED AIRCRAFT TECHNCIANS (Remove the following items from aircraft continued) 25. Remove aircraft from hoist and add air to tires as required. 26. Install wing-root fairings. 27. Check all placards to conform to landplane category. 28. Make logbook entry. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 94 of 104 Revision D INSP. MECHANIC Lt. Rt. FLOAT RE-INSTALL INSTRUCTIONS/PROCEDURES THIS IS INTENDED AS A GENERAL GUIDE. EACH INSTALLATION MAY HAVE SUBTLE DIFFERENCES. ALWAYS USE THE INSTALLATION DRAWINGS AS THE FINAL REFERENCE. ALL WORK SHOULD BE DONE BY CERTIFIED AIRCRAFT TECHNICIANS. 1. Remove the nose and main gear fairings and the belly plate. 2. Remove wing gap strips and the tail cover. 3. Install the finlets and seal. 4. Remove aft panel inspection covers for Hydraulic pump access and cables. 5. Remove pilot and Co-pilot steps. 6. Replace Passenger Door Cable Assy. (2) P/N S2837-1 with Cargo Door Cable Assy. (2) P/N S2837-2 7. Install front strut fittings. 8. Disconnect brake lines and cap. 9. Cut Tie-wrap from pump circuit breakers. 10. Tie ropes from tie-down rings. Connect lifting bar to hoist and inspect aircraft lifting rings for proper assembly before connecting to aircraft. Use ballast from tie-down to ensure level lifting. 11. Raise aircraft until wheels are just touching the ground and assemble. 12. Assemble support crew, minimum six (6) crew members. 13. Remove saddles holding main gear in place. With crew support crew stabilizing aircraft, hoist aircraft clear of main gear and roll away from aircraft. 14. Lube saddles on aircraft and saddle bolts and position floats under aircraft. 15. Lower aircraft to floats, install front struts first then lower aircraft onto Saddles and install clamps. 16. Torque the saddle bolts to 75ft/lbs. 17. Remove the Nose gear. 18. Install the flying wire fitting. Install flying wires, rig with regard to airflow. 19. Secure the steering bungee and connect the hydraulic lines. 20. Locate jack stands under floats. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision F Page 95 of 104 P/N 1005723 Doc. No. W8750-24-01 INSP. NOTES: MECHANIC Lt. Rt. FLOAT RE-INSTALL INSTRUCTIONS/PROCEDURES (CONT.) THIS IS INTENDED AS A GENERAL GUIDE. EACH INSTALLATION MAY HAVE SUBTLE DIFFERENCES. ALWAYS USE THE INSTALLATION DRAWINGS AS THE FINAL REFERENCE. ALL WORK SHOULD BE DONE BY CERTIFIED AIRCRAFT TECHNICIANS. (Re-Install from aircraft continued) 21. Perform gear check and ensure all lights agree with gear position and gear advisory. 22. Cycle time up? Cycle time down? Check for leakage 23. Hand pump the gear down and up and check for leakage. 24. Install springs for steering cables in the tail of the aircraft. 25. Route and rig the steering cables and water rudder retract cables with 30lbs. +/- 5lbs. 26. Install step struts. 27. Install brake lines and bleed for air bubbles (See Chapter 5 section 5.1 this manual). 28. Install elevator down-spring. 29. Install belly plate and fairings for main gear. 30. Install tail inspection cover, cowling, and wing gap strips. 31. Inflate tires IAW Chapter 1 Figure 1-8 of this manual. 32. Remove aircraft from stands, check for proper main oleo extension (see Section 4) 33. Check aircraft placards against the flight manual supplement or install drawings for accuracy. 34. Plug nose leg fairing holes, pilot, and Co-pilot step holes. 35. Make logbook entry. SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 96 of 104 Revision C 9.4: WEIGHING PROCEDURES FOR CESSNA 208/208B, CARAVAN Level aircraft per manufacturer’s instructions or use the cabin door lower sill. Place scales under the right and left main and nose gears. Place blocking under the right and left main gears to level aircraft. Draw lines on the floor from the centerline main wheels and centerline nose wheel left to right. Drop a plumb bob from the face of the firewall. This is station 100.00. Measure 100.00 inches forward of this point, this is the datum, 0.0. Draw another line between the nose wheel centers and a 4th line between the main wheel centers. Measure the distance from 0.0 to the nose wheel line. This is X1 and X2. Measure the distance from 0.0 to the main wheel line. This is Y1 and Y2. If the floats are seaplane floats, the scales go under the step point in the rear and a point towards the front of the float. These distances are measured and become the same X and Y as for the amphibian. Scale Reading Distance from 0.0 Weight x Arm Weight x Arm = Moment Left Front Right Front Left Rear Right Rear Totals Notes: 1. Zero out or deduct tare weights at the Y arm. + + X1 + + + X2 + + + Y1 + + + Y2 + SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B Revision B Page 97 of 104 P/N 1005723 Doc. No. W8750-24-01 CHAPTER 10 TROUBLESHOOTING SERVICE MANUAL & ICA 8750 AMPHIBIAN/SEAPLANE FLOATS ON CESSNA 208/208B P/N 1005723 Doc. No. W8750-24-01 Page 98 of 104 Revision IR Corrective Action a. Reset circuit breaker b. Jump across pressure switch leads to determine if