SERVICE LETTER NO. 1302

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Piper Aircraft, Inc. 2926 Piper Drive Vero Beach, FL, U.S.A. 32960 Date: December 1, 2022 (S) (OVER) SERVICE LETTER NO. 1302 ATA/JASC: 2821 SUBJECT: REPLACEMENT OF LOCKING GASCOLATOR DRAIN VALVE MODELS AFFECTED: SERIAL NUMBERS AFFECTED: Group A: PA-11 Cub Special All PA-15 Vagabond All PA-16 Clipper All PA-17 Vagabond All PA-18/-18A/-19 Super Cub All PA-20 Pacer All PA-22-125/-135/-150/-160 Tri-Pacer / Caribbean All PA-22-108 Colt All Group B: PA-28-140 Cherokee 140 All PA-28-150/-160 Cherokee 150 / 160 All PA-28-180 Cherokee 180 All PA-28-151 Cherokee Warrior All PA-28-161 Cherokee Warrior II 28-7716001 through 28-8616057, 2816001 through 2816096 PA-28-161 Cadet 2841001 through 2841290 PA-28-181 Archer II 28-7690001 through 28-7990626, 28-8090001 through 8690056, 2890001 through 2890145 PA-28-201T Turbo Dakota All PA-28-236 Dakota 28-7911001 through 28-8611009, 2811001 through 2811032 PA-28R-180 Arrow All PA-28R-200 Arrow II All PA-28R-201 Arrow III 28R-7737001 through 28R-7837317, 2837001 through 2837043 PA-28R-201T Turbo Arrow III All PA-28RT-201 Arrow IV All PA-28RT-201T Turbo Arrow IV All SERVICE LETTER NO. 1302 PAGE 2 of 8 COMPLIANCE TIME: At owners/operators discretion. APPROVAL: The engineering aspects of this service document have been shown to comply with the applicable Federal Aviation Regulations and are FAA approved. PURPOSE: Before 1990, Piper airplanes were equipped with a gascolator assembly (aka the fuel strainer bowl or fuel filter bowl) manufactured with a locking drain valve. Starting in 1990, Piper replaced the locking drain valve with a non-locking drain valve. Due to its locking capability, locking drain valves could be left open through operator error, after the completion of the preflight checklist. While an engine is operating, an open gascolator drain valve could allow air to enter the fuel system or it could drain fuel from the tanks. Either of these conditions could lead to fuel starvation and engine failure. To prevent the possibility of the gascolator drain valve being left locked open, Piper recommends replacing any installed locking drain valve with the non-locking drain valve. INSTRUCTIONS: NOTE: Early Piper Aircraft models were certified under CAR 3 rules and there is no regulatory requirement for a manufacturer’s maintenance manual. For aircraft models that do not have a maintenance manual, Piper recommends the use of AC 43.13-1B (latest revision). See also “Civil Aeronautics Manual 18”. 1. Remove the engine cowling. Refer to Chapter 71-10-00 of the appropriate Airplane Maintenance Manual (AMM) or Powerplant section of the appropriate Service Manual (SM) for instructions on cowling removal. 2. Locate the gascolator assembly, mounted on the forward left side of the firewall as shown in Figure 1. Inspect and determine which drain valve is installed. • If a locking fuel drain valve is installed, proceed to step 3. • If a non-locking fuel drain valve is installed, proceed to step 8. 3. Pull the main power circuit breaker to the OFF position and set the fuel selector valve to the OFF position. 4. Remove the gascolator from the airplane. Refer to Chapter 28-20-00 of the appropriate AMM or Fuel System section of the appropriate SM for instructions on gascolator removal. NOTE: Before removing, drain fuel from the gascolator bowl. Use a suitable container to collect the drained fuel. 5. Remove the locking fuel drain valve from the gascolator and install the non-locking fuel drain valve as shown in Figure 2. 6. Install the gascolator assembly. Refer to Chapter 71-10-00 of the appropriate AMM or Fuel System section of the appropriate SM for instructions on gascolator installation. CAUTION: TAKE CARE TO ENSURE NO FIRE HAZARD EXISTS BEFORE RESTORING POWER TO AIRPLANE. 7. Reset the main power circuit breaker to the ON position and set the fuel selector valve to the LEFT or RIGHT fuel tank. Turn ON the fuel pump and pressurize the fuel system to check the gascolator assembly for leaks. Turn OFF fuel pump and correct any leaks found. 8. Install the engine cowling. Refer to Chapter 71-10-00 of the appropriate Airplane Maintenance Manual (AMM) or Powerplant section of the appropriate Service Manual (SM) for instructions on cowling installation. 9. Complete a logbook entry documenting compliance with this service letter. SERVICE LETTER NO. 1302 PAGE 3 of 8 Figure 1 (Sheet 1 of 3) Gascolator Drain Valve FWD UP SEE DETAIL A SIDE VIEW LEFT SIDE LOOKING INBOARD (PA-18-150 SHOWN, OTHER GROUP A MODELS SIMILAR) DETAIL A GASCOLATOR ASSEMBLY SEE DETAILS C & D SERVICE LETTER NO. 1302 PAGE 4 of 8 Figure 1 (Sheet 2 of 3) Gascolator Drain Valve SEE DETAIL B SIDE VIEW LEFT SIDE LOOKING INBOARD (PA-28-181 SHOWN, OTHER GROUP B MODELS SIMILAR) FWD UP DETAIL B GASCOLATOR ASSEMBLY SEE DETAILS C & D SERVICE LETTER NO. 1302 PAGE 5 of 8 Figure 1 (Sheet 3 of 3) Gascolator Drain Valve DETAIL C NON-LOCKING DRAIN VALVE (P/N 492-312) DETAIL D LOCKING DRAIN VALVE (P/N 492-022) NO LOCKING SHOULDER LOCKING SHOULDER SERVICE LETTER NO. 1302 PAGE 6 of 8 Figure 2 (Sheet 1 of 2) Installation of Non-Locking Drain Valve DRAIN VALVE (P/N 492-312) SEE NOTE GASOLATOR BOWL GASCOLATOR BOWL ASSEMBLY GROUP A MODELS NOTE INSTALL WITH VALVE CLOSED. USE LOCTITE #567, IN ACCORDANCE WITH MANUFACTURER’S INSTRUCTIONS. DO NOT ALLOW LOCTITE TO ENTER SYSTEM. INSTALL VALVE BY HAND WITH A MINIMUM OF 2 ½ TURNS, A MAXIMUM OF 3 ½ TURNS INTO GASCOLATOR BOWL. SERVICE LETTER NO. 1302 PAGE 7 of 8 Figure 2 (Sheet 2 of 2) Installation of Non-Locking Drain Valve DRAIN VALVE (P/N 492-312) SEE NOTE 1 SEALING LOCKNUT (P/N 458-946) SEE NOTE 2 ELBOW ADAPTER GASCOLATOR BOWL NOTES 1. INSTALL WITH VALVE CLOSED. USE SEALANT, LOCTITE #290, IN ACCORDANCE WITH MANUFACTURER’S INSTRUCTIONS. APPLY A MAXIMUM APPLICATION OF ONE DROP COATING ON 2ND, 3RD, AND 4TH THREADS EVENLY. DO NOT ALLOW LOCTITE TO ENTER SYSTEM. INSTALL VALVE WITH A MINIMUM OF 2 ½ TURNS, A MAXIMUM OF 3 ½ TURNS IN ADAPTER.