Oil Leak??
Thread Starter
Cruising
Joined: Mar 2003
Posts: 13
Likes: 0
From: Cold Lake Alberta
Oil Leak??
My 77 with 350 ZZ3 has a leak that I cannot find. The rearmost spark plug boot on the passenger side and the starter and wiring below get coated with motor oil. With the car in park I have cleaned the area up and then watched and revved the engine up with no sign of leakage. Valve cover(centerbolt) is snug. Seems to show up after a cruise. Would appreciate any suggestions?
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
I would run your finger just under the valve cover to see if there is any oil seepage. Since the oil leak is probably coming from it, I would replace the gasket as oil generally runs down, not up. Be sure not to over tighten the bolts as this can damage the sealing ability of the gasket.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
I would run your finger just under the valve cover to see if there is any oil seepage. Since the oil leak is probably coming from it, I would replace the gasket as oil generally runs down, not up. Be sure not to over tighten the bolts as this can damage the sealing ability of the gasket.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
It's very possible it's coming from that troublesome rear intake seal. Wash everything down thoroughly so no oil remains. Take her out for a drive, slow speeds to keep wind in the engine bay to a minimum, and park and take a peek with a flash light.
You should start to see seeping at this point. Watch at the bottom edge at the back of the valve cover, and at the back of the engine where the rear seal is.
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Thread Starter
Cruising
Joined: Mar 2003
Posts: 13
Likes: 0
From: Cold Lake Alberta
Thanks for the advice. Have a spare valve cover gasket so I'll replace that. The test drive will have to wait, got a pesky 4ft snow drift in front of the garage door!! One way or another this problem will be solved this spring.
Valve cover gasket, slight seep and then a little drop...Try some thick corks and even torque on all bolts. The corks have limited lifespan though.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
How's the snow problem? You had time to mess with the leak yet?