Skyhawk L4-121 2.0L Turbo VIN M FI (1987)
Crankshaft Main Bearing Seal: All Technical Service Bulletins
Engine - Rear Main Seal Noise
Bulletin 87-6-15
Date
June '87
Ref. No. 87-137-6
Corp. Ref. No. 706006
SUBJECT:
DIAGNOSIS OF REAR MAIN SEAL NOISE
MODELS AFFECTED: 1987 SKYHAWKS (WITH THE LL8 2.0L L-4 ENGINE VIN CODE 1)
Reports have been received of rear main seals being replaced because of a "chirping" or "squealing" noise that goes away when an oil is sprayed into that
area. However, improper engine ventilation can produce an internal vacuum depression which draws air past the seal.
If the noise symptom disappears when the oil dipstick is removed (preventing internal vacuum depression), check the fresh air feed hole in the air inlet
rubber duct for blockage where it connects to the metal pipe going to the rocker cover. Cut out any blockage to eliminate the noise problem and the need
for rear seal replacement.
WARRANTY INFORMATION
Labor Operation Number:
T1224
Labor Time:
.3 Hour
Trouble Code:
92
