DIAGNOSING TRANSMISSION OIL LEAKS - THM 700R4

TO DIAGNOSE A TRANSMISSION OIL LEAK PROPERLY THE FOLLOWING PROCEDURE SHOULD BE USED. DIAGNOSIS PROCEDURE: THE FOLLOWING PROCEDURE IS PREFORMED ON CAR. 1. CLEAN ALL RESIDUAL OIL FROM THE TRANSMISSION. (C.R.C.'S ELECTRA- MOTIVE CLEANSER, OR EQUIVALENT IS RECOMMENDED). REPEAT CLEANING PROCESS UNTIL ALL RESIDUAL OIL IS REMOVED. 2. DUST THE ENTIRE TRANSMISSION WITH A WHITE POWDER (EG. LEAK TRACING POWDER OR SPRAY FOOT POWDER). IF RESIDUAL OIL IS LEFT ON THE TRANSMISSION, IT WILL NECESSITATE THE CLEANING AND DUSTING PROCEDURE BE REPEATED. 3. AFTER NORMAL OPERATING TEMPERATURE (170 DEGREES F) HAS BEEN OBTAINED, LET THE TRANSMISSION STAND FOR AT LEAST THIRTY (30) MINUTES (ENGINE OFF). 4. INSPECT THE TRANSMISSION FOR LEAKAGE BY FOLLOWING RED OIL TRACES LEFT IN THE POWDER. 5. ONCE THE LEAK HAS BEEN DIAGNOSED AS TO LOCATION AND TYPE (WETNESS, MOIST, DAMP, ETC.) REFER TO THE FOLLOWING REPAIR PROCEDURE: IMPORTANT: STEPS 1-4 SHOULD BE USED WHEN DIAGNOSING ANY TRANSMISSION FOR AN OIL LEAK. 6. REPEAT STEPS 1-4 FOLLOWING REPAIR OF SUSPECT LEAK SOURCE. FIGURE ITEM PART NAME LEAK CAUSE CORRECTION NUMBER NO. 1 1 TRANS. OIL PAN -LOW BOLT TORQUE -RETORQUE AND RE- CHECK BOLTS -GASKET LEAK -REPLACE GASKET 1 2 CASE -POROSITY -REPAIR PER SERVICE MANUAL -CRACKED -REPLACE CASE 1 3 COOLER FITTINGS -LOW TORQUE -RESEAL AND RE- OR PRESSURE TORQUE PLUGS -RECHECK 1 4 T.V.CABLE -CONNECTOR COCKED -REMOVE CONNECTOR CONNECTOR AND INTERFERING AND REINSTALL WITH MOUNT -SEAL DAMAGED -REPLACE SEAL -CONNECTOR -REPLACE CONNECTOR CRACKED CABLE 1 5 SERVO COVER -POROSITY -REPLACE(SEE FIG.2) 2 1&2 -"O" RING DAM- -REPLACE(SEE FIG.2) AGED 1 6 FILL TUBE -SEAL MISSING OR -REMOVE FILL TUBE DAMAGED AND REPLACE SEAL -TUBE BENT ABOVE -REPLACE TUBE TRANSMISSION 1 7 CONVERTER SEAL -SEAL DAMAGED -REPLACE SEAL 3 - -SEAL BLOWN OUT -(SEE FIG.3)CHECK FOR OVERSIZED SEAL BORE OR RE- STRICTED DRAIN- BACK PASSAGE. 1 8 PUMP ASSEMBLY -PUMP BOLTS LOOSE -RETORQUE AND RE- CHECK -PUMP TO CASE RING -REMOVE AND RE- CUT OR DAMAGED PLACE RING RE- CHECK. IF LEAK PERSISTS, REPLACE OIL PUMP BODY WITH PART NO. 8642986) OR REPAIR (SEE FIG. 3) 3 - -PUMP POROSITY -REPLACE PUMP BODY PART NO.8642986 1 9 CONVERTER ASM. -HUB OR SEAM -REPLACE CONVERTER WELD LEAK 1 10 VENT -LEAKING -CHECK FOR OIL OVERFILL AND CORRECT AS NECESSARY 1 11 ELECTRICAL -"O" RING MIS- -REMOVE CONNECTOR CONNECTOR SING OR DAMAGED AND REPLASE SEAL -CONNECTOR -REPLACE CONNECTOR DAMAGED 1 12 MANUAL SHAFT -SEAL ASSEMBLY -REPLACE SEAL DAMAGED 1 13 GOVERNOR COVER -GAPS IN SEALANT -RESEAL (LOCTITE OR R.T.V. 1 14 SPEEDO FITTING -LOW BOLT TORQUE -RETORQUE BOLT AND RECHECK -SEAL DAMAGE -REPLACE SEAL 1 15 REAR EXTENSION -POROSITY -REPAIR PER SER- VICE MANUAL -CRACKED -REPLACE -LOW BOLT TORQUE -RETORQUE AND RE- CHECK -EXTENSION TO -REPLACE SEAL CASE SEAL DAM- AGED -EXTENSION SEAL -REPLACE SEAL ASSEMBLY TORN OR DAMAGED

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