Engine - Oil/Coolant Leak Diagnostic Tip

Group 11
Engine

Bulletin Number
11 04 98

Woodcliff Lake, NJ
April 1998
Product Engineering

SUBJECT:
Engine Oil / Coolant Leaks

MODEL:
All with M60 and M62 engines

Situation:

If an engine oil or coolant leak develops in the center or valley of a V8 engine it may be misleading to diagnose due to the fluid flow path.





A leak which occurs in the engine valley due to a poor sealing cylinder head gasket, valley cover gasket, etc. will allow fluid to flow toward the rear of the engine and exit the weep holes in the rear of the block. (see illustration)

From the weep holes the fluid will flow down the rear of the engine block and end up at the transmission bell housing area.

This type of engine oil or coolant leak may appear to be coming from the rear crank shaft oil seal or rear coolant channel cover since the leaking fluid exits at the transmission bell housing area.

Diagnostic Tip:

If an engine oil or coolant leak is detected at the bottom of the transmission bell housing area, the center sound absorbing engine cover should be removed first to inspect the engine valley for signs of fluid leaks.

This will avoid an unnecessary transmission removal and installation to gain access to a rear crank shaft main seal or coolant channel gasket which may not be leaking.

Warranty Information:

Information only.