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*Piston* · 11-08-2002, 10:45 PM

Double check the missing bolt as Chucks70 mentioned. Very common and will usually leak very bad at highway speeds and not so much while idling.

Degrease the engine and let it dry, make sure your oil level is good then find a nice clean/dry area to let your truck run a bit.

Once things are dry and you have a clean area, start the engine and let it idle for a few minutes while checking for leaks. See any leaks underneath yet? While the engine is still somewhat dry, you'll be able to trace back to the source of the leak. If no, raise the rpm to 1200 or so (first step on a Q-jet carb choke) while checking for leaks. Look closely at the intake end rails(where the block meets the intake). If after 10 minutes of run time and you still have no leaks, may be time to take it in. Find someone thats willing to do a dye leak detection. They will add a few ounces of oil dye and verify your leak using a blacklight. (this is the basic procedure I would take at the shop)

You mentioned the front seal/timing cover, did you check your harmonic balancer shaft? the seals create a very deep groove in the balancer sealing area and will leak. If so, install a harmonic balancer sleeve.

11-08-2002, 10:45 PM	#3
Piston Account Suspended Join Date: Oct 2002 Location: Olathe, KS Posts: 2,300	Double check the missing bolt as Chucks70 mentioned. Very common and will usually leak very bad at highway speeds and not so much while idling. Degrease the engine and let it dry, make sure your oil level is good then find a nice clean/dry area to let your truck run a bit. Once things are dry and you have a clean area, start the engine and let it idle for a few minutes while checking for leaks. See any leaks underneath yet? While the engine is still somewhat dry, you'll be able to trace back to the source of the leak. If no, raise the rpm to 1200 or so (first step on a Q-jet carb choke) while checking for leaks. Look closely at the intake end rails(where the block meets the intake). If after 10 minutes of run time and you still have no leaks, may be time to take it in. Find someone thats willing to do a dye leak detection. They will add a few ounces of oil dye and verify your leak using a blacklight. (this is the basic procedure I would take at the shop) You mentioned the front seal/timing cover, did you check your harmonic balancer shaft? the seals create a very deep groove in the balancer sealing area and will leak. If so, install a harmonic balancer sleeve.