Never Ending Oil Leaks
Thread Starter
Burning Brakes
Joined: Jul 1999
Posts: 1,110
Likes: 0
From: Andover MA
Cruise-In I Veteran
Never Ending Oil Leaks
I've had my '94 for two years now and have been fighting oil leaks since day 1. I had the intake manifold gaskets replaced and the front crank and waterpump seals replaced. Now, it appears that 1 lower bolt on the timing chain cover is leaking and I think the rear main seal is leaking as well. I spoke with a mechanic last night at my Covette club's cruise night and he told me that a quick fix for the leaking bolt was to remove it and apply some Permatex and put it back in tight. Have any of you heard of some tricks for stopping these leaks? What's involved with replacing the main rear? I understand it's a big job!
Melting Slicks
Joined: Jun 2000
Posts: 2,923
Likes: 1
From: Las Vegas NV
Re: Never Ending Oil Leaks (mshipon)
I believed that you need to drop the trans. to change the rear main seal :yesnod:
I need to do that to my 88 too, and I don't want to do it at home. Please post how much the mechanic charge you to change the rear main.
I need to do that to my 88 too, and I don't want to do it at home. Please post how much the mechanic charge you to change the rear main.
Racer
Joined: Jan 2001
Posts: 324
Likes: 0
Re: Never Ending Oil Leaks (mshipon)
Are there oil drops on the ground when you park the car? Or is there "just" some oil on the engine?
If car is not really leaving oil spots on the floor, I'd stop fighting those leaks. There are not many engines around which are really "dry"...
If car is not really leaving oil spots on the floor, I'd stop fighting those leaks. There are not many engines around which are really "dry"...
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Never Ending Oil Leaks (Klaus)
I think I've got a leak from the oil filter adapter, or possibly the rear main seal. It leaves a few drops a night. Nothing big to me, because I change the oil ever 2500 miles or so and with a few drops every night it won't get low enough to cause a problem. Obviously I check the oil level more often than I would have my other cars.
Safety Car
Joined: Mar 2000
Posts: 3,620
Likes: 2
From: Hillsboro OR
Re: Never Ending Oil Leaks (mshipon)
The permatex on the bolt should work. The rear main seal might actually be that oil filter adapter. The original gaskets on it suck. GM has a new design for it. The oil filter may not be on tight enough. Its small and hard to tighten so it may not be on all the way. I had this problem until I made sure it was at least 3/4 to 1 full turn after the gasket contacts the adapter.
The bolts holding stuff to the engine get loose over time because of the thermal cycling the engine. This eventually promotes oil leaks. Its a good idea to tighten the bolts on those areas once ever 12 to 18 months. The key items are intake, throttle body, waterpump, timing cover and probably the oil filter adapter. Anything aluminum that is bolted on (besides the heads) is a possible source since Aluminum expands more than the cast iron block when it heats up.
Frankly, I wish the EPA would set some guidelines for oil leaks. They are a really big source of oil going into the ground. The side benefit for us is that the engine would leak a lot less oil and stay cleaner.
The bolts holding stuff to the engine get loose over time because of the thermal cycling the engine. This eventually promotes oil leaks. Its a good idea to tighten the bolts on those areas once ever 12 to 18 months. The key items are intake, throttle body, waterpump, timing cover and probably the oil filter adapter. Anything aluminum that is bolted on (besides the heads) is a possible source since Aluminum expands more than the cast iron block when it heats up.
Frankly, I wish the EPA would set some guidelines for oil leaks. They are a really big source of oil going into the ground. The side benefit for us is that the engine would leak a lot less oil and stay cleaner.
Thread Starter
Burning Brakes
Joined: Jul 1999
Posts: 1,110
Likes: 0
From: Andover MA
Cruise-In I Veteran
Re: Never Ending Oil Leaks (AquaMetallic94LT1)
AquaMetallic94LT1,
Thanks for the tips. They really seem to make good sense. I just got home from Corvettes At Carlisle, but will check it out after work tomorrow.
I hope you're right!
Thanks for the tips. They really seem to make good sense. I just got home from Corvettes At Carlisle, but will check it out after work tomorrow.
I hope you're right!
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Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Never Ending Oil Leaks (mshipon)
I'm pretty sure the oil filter adapter is the cause for my leaks. I know the oil filter is on plenty tight and oil still drips right off the filter (even after 3 changes), so I figure it has to be that adapater.
That part number, does it include both the adapter and the o-ring? There are several pieces listed in the service manual that compose the oil/adapter setup (about 5 of them it looks like).
[Modified by Glock'94, 5:56 PM 8/27/2001]
That part number, does it include both the adapter and the o-ring? There are several pieces listed in the service manual that compose the oil/adapter setup (about 5 of them it looks like).
[Modified by Glock'94, 5:56 PM 8/27/2001]
Thread Starter
Burning Brakes
Joined: Jul 1999
Posts: 1,110
Likes: 0
From: Andover MA
Cruise-In I Veteran
Re: Never Ending Oil Leaks (Glock'94)
Curtis... Jeff Kopp stated that the kit includes the gasket and the o-ring. I assume that's all you need. Let me know if you find out some other information.
Thanks!
Thanks!
Thread Starter
Burning Brakes
Joined: Jul 1999
Posts: 1,110
Likes: 0
From: Andover MA
Cruise-In I Veteran
Re: Never Ending Oil Leaks (mshipon)
Alright, I'm starting to get really mad now!!! :mad I got home from Carlise and checked under the car and there was more oil on the front bottom of the engine and spraying back on everything. I've already had the intake manifold gasket changed and just last week had the crank seals replaced when I had my opti and waterpump replaced. My mechanic checked it today before work and cannot really seem to diagnose where the heck it's coming from. He resealed a few timing chain cover bolts with RTV, but we doubt that's the problem. The oil filter is completely dry. Actually, the oil level was fine, so whatever is leaking, is being blown all over the place.
He want's to take the crank pulley off and thoroughly recheck the crank seal and the oil pan seal. Does anyone have any other ideas? What's involved with changing the oil pan seal? Does the engine need to be raised?
I'm worried :( that the new opti may get wet and blow out again $$$. My wife is going to kill me!!!
Please help or send money to.... (just kidding)
He want's to take the crank pulley off and thoroughly recheck the crank seal and the oil pan seal. Does anyone have any other ideas? What's involved with changing the oil pan seal? Does the engine need to be raised?
I'm worried :( that the new opti may get wet and blow out again $$$. My wife is going to kill me!!!
Please help or send money to.... (just kidding)
