95 LT1 Oil Leak
Thread Starter
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Joined: Nov 2003
Posts: 61
Likes: 0
From: Tampa Florida
95 LT1 Oil Leak
It looks like I have an oil leak on the front of the motor. With a flashlight and a mechanics mirror I can see oil on the Opti-Spark and the front of the motor. I can't tell exactly where it is coming from but from reading the posts on the forum I suspect the direct drive on the water pump. I get about 3-5 drops on the garage floor per night. Funny enough my oil never registers low!
My question(s)...would you replace the pump with an electrical unit or rebuild the orginal and put a new seal on the direct drive?
Has anyone replaced the seal on the direct drive without the leak returning?
How hard is it to upgrade to an electric unit and remove the direct drive shaft and plug the hole in the timing chain cover? Can it be done without removing the harmonic balancer and the timing cover? I'd rather not get into that if at all possible.
Should I replace the Opti? I've read a lot of horror stories on the forum about it giving up the ghost with no warning.
What else should I do while I'm working in that area? The car has 110K miles on it. Should I upgrade to a better than stock radiator/fans/thermostat? It runs aroun 193 while cruising and up to 225 at a stop or in traffic until the fan comes on or I crank the a/c.
I appreciate your help.
AimHI
My question(s)...would you replace the pump with an electrical unit or rebuild the orginal and put a new seal on the direct drive?
Has anyone replaced the seal on the direct drive without the leak returning?
How hard is it to upgrade to an electric unit and remove the direct drive shaft and plug the hole in the timing chain cover? Can it be done without removing the harmonic balancer and the timing cover? I'd rather not get into that if at all possible.
Should I replace the Opti? I've read a lot of horror stories on the forum about it giving up the ghost with no warning.
What else should I do while I'm working in that area? The car has 110K miles on it. Should I upgrade to a better than stock radiator/fans/thermostat? It runs aroun 193 while cruising and up to 225 at a stop or in traffic until the fan comes on or I crank the a/c.
I appreciate your help.
AimHI
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Re: 95 LT1 Oil Leak (AimHi)
Are you sure it isn't the front of the intake? This is by far the most common leak on the LT1. The front and rear intake seals where not sealed properly from the factory and are prone to leak.
Thread Starter
Advanced
Joined: Nov 2003
Posts: 61
Likes: 0
From: Tampa Florida
Re: 95 LT1 Oil Leak (AimHi)
It doesn't appear to be on the front of the manifold but I certainly won't rule that out until I take of the air intake and get a good look at it.
Thanks
Thanks
Heel & Toe
Joined: Mar 2004
Posts: 21
Likes: 0
From: Prince George B.C.
Re: 95 LT1 Oil Leak (AimHi)
Tore my engine apart yesterday to find exactly the same problems, hard to tell which was worse, opti-spark or water pump drive, intake is good, going to replace water pump & all three front cover seals. Replacing with electric pump seems like a lot of work. You'll more than likely have to drop the pan to pull front cover & fill the water pump drive hole. Besides, if it lasts another ten years it's not that bad of a job...
Drifting
Joined: Jun 2001
Posts: 1,997
Likes: 1
From: Lake Ozark MO
Re: 95 LT1 Oil Leak (AimHi)
Man, it's GM.. I pulled my engine and replaced every gasket and seal. My oil filter adapter still gives its best effort to seep and the crank sensor o-ring is too lazy to do its job as well.
I must've got the Friday castings.
I must've got the Friday castings.
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Re: 95 LT1 Oil Leak (AimHi)
I agree that you need to eliminate the intake manifold as the source. Look for fresh oil weeping from the front and rear seals. You may also want to check for loose bolts on the corners of the intake manifold.
Coolant temp seems very normal, so I would not touch the cooling system. You should do the normal flush refill however.
Tom
Coolant temp seems very normal, so I would not touch the cooling system. You should do the normal flush refill however.
Tom
Le Mans Master
Joined: Feb 2000
Posts: 9,061
Likes: 214
From: Epping NH
Re: 95 LT1 Oil Leak (Mez)
I had the infamous intake oil leak one time, but before replacing the gaskets, I decided to check the torgue settings of the intake manifold bolts. The suckers where way off.
Tighten the bolts to specs and the oil leak disappeared. 2 years later still no leak. I think this is a simple step a lot of people over look and end up doing more work then maybe needed.
Tighten the bolts to specs and the oil leak disappeared. 2 years later still no leak. I think this is a simple step a lot of people over look and end up doing more work then maybe needed.
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Le Mans Master
Joined: Feb 2002
Posts: 7,858
Likes: 2
Re: 95 LT1 Oil Leak (AimHi)
Its a car thing... I don't think brand even matters. My '94 Dakota drips once in a while. The '97 Taurus fleet car I drive for work drips once in a while. My Vette has had the intake seals replaced and the opti replaced and they suppsoedly replaced the timing cover seal during the opti job, but... I get a light wide film of oil that comes down the front of the engine somewhere and coats the front and bottom of the oil pan. I took it to the dealer, they added flourescent dye and black lighted it (it was under GMPP ext warranty at the time, otherwise would not have used dealer), then they proclaimed that it was not leakage but "condensation". Huh? Since when does MOTOR OIL form as condensate? :cuss Anywho, they said they could not find any oil on the exterior of the engine flouresing under the black light, so it wasn't much of a leak at all, and no change to the dipstick between oil changes. Just a little quarter or nickel size oily spot on the garage floor, so... I don't worry about it.
Race Director
Joined: Feb 2003
Posts: 11,672
Likes: 20
From: Lake Wylie SC
Re: 95 LT1 Oil Leak (AimHi)
Here is an article I wrote last year and it might help you out. I had the same leak. https://www.corvetteforum.com/techti...=231&TopicID=2
Have some fun with it.
Have some fun with it.
