TRANSMISSION OIL PAN LEAKS NEW OIL PAN200-200C

BEGINNING SEPTEMBER 6, 1983 A NEW TRANSMISSION OIL PAN (FIGURE 1) AND HEX HEAD SCREW AND CONICAL WASHER ASSEMBLY (FIGURE 2) WENT INTO PRODUCTION FOR ALL THM 200C TRANSMISSIONS. REFER TO THE CHART BELOW AND VERIFY SERIAL AND MODEL NUMBERS. IF THE SERIAL NUMBER IS PRIOR TO THE NUMBER ON THE CHART THEN FOLLOW THIS PROCEDURE. MODEL SERIAL BH 48567 OI 17716 CZ 1041 JY 1074 OR 1071 OU 1724 SERVICE PROCEDURE: 1. DIAGNOSE SOURCE OF LEAK TO BE CERTAIN LEAK IS FROM THE TRANSMISSION OIL PAN AREA. (REFER TO SERVICE BULLETIN HM 83-44 FOR DIAGNOSING TRANSMISSION OIL LEAKS). 2. IF A LEAK IS DETERMINED TO BE FROM THE TRANSMISSION OIL PAN AREA: - REMOVE THE OIL PAN AND GASKET - CLEAN THE CASE OIL PAN FACE (WITH SOLVENT) AND VISUALLY INSPECT THE CASE OIL PAN FACE FOR NICKS, AND R.T.V. SEALANT (ROOM TEMPERATURE VULCANIZING SEALANT). MAKE SURE ALL R.T.V. SEALANT IS REMOVED FROM THE CASE OIL PAN FACE. 3. IF THE THM 200 TRANSMISSION BEING SERVICED IS A 1979 OR EARLIER MODEL VERIFY WHICH TRANSMISSION OIL SCREEN IS BEING USED. (FIGURE 3) IF THE OLD OIL SCREEN IS BEING USED (FIGURE 3) IT MUST BE REPLACED WITH THE NEW OIL SCREEN (FIGURE 3) PROVIDED IN THE SERVICE PACKAGE. 4. REPLACE THE FORMER OIL PAN (FIGURE 1) HEX HEAD SCREWS (FIGURE 2) WITH NEW OIL PAN (FIGURE 2) AND HEX HEAD SCREW AND CONICAL WASHER ASSEMBLIES. (FIGURE 2) ORDER SERVICE PACKAGE 8638929. THIS SERVICE PACKAGE CONTAINS THE FOLLOWING: 1 - 8648160 - NEW OIL PAN 1 - 8648161 - TRANSMISSION OIL PAN GASKET 11 - 8643683 - HEX HEAD SCREW AND CONICAL WASHER ASSEMBLY 1 - 8630789 - SCREEN ASSEMBLY TRANSMISSION OIL 1 - 8628300 - GASKET, SCREEN TO VALVE BODY 1 - 8632952 - INSTRUCTION SHEET THESE PARTS ARE ALSO AVAILABLE SEPARATELY. TORQUE ALL HEX HEAD SCREEN TO 11.0 N.M. (9.0 FT. LBS.) THEN RETORQUE ALL THE HEX HEAD SCREWS A SECOND TIME TO THE SAME SPECIFICATIONS AS ABOVE. THE SECOND RETORQUE IS IMPORTANT BECAUSE THE GASKET MATERIAL RELAXES AFTER THE FIRST TIGHTENING.

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