Oil leak question
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 27
Likes: 0
From: CO
Oil leak question
So a little back story. The gentleman that previously owned the car was a bit of a mechanical "hot mess" Not a DIY sort of guy. He was running the car about 95 and started blowing a lot of smoke. Oil on the exhaust type of smoke. My job is to fix this problem....
I don't see much of a leak when the car is sitting. It hardly leaks at all when idling.. When you start to drive and things get pressurized, thats when the fun starts.
I have one valve cover gasket replaced which didn't fix anything..
I see oil pooling here in front of the block
Is there a high pressure oil line here? would that be something that would leak if the RPM's were high? The car has 88K miles, and has sat for awhile, so it's possible a hose or seal has split/cracked.
I am just looking for a starting point.
Thanks!
Shawn
I don't see much of a leak when the car is sitting. It hardly leaks at all when idling.. When you start to drive and things get pressurized, thats when the fun starts.
I have one valve cover gasket replaced which didn't fix anything..
I see oil pooling here in front of the block
Is there a high pressure oil line here? would that be something that would leak if the RPM's were high? The car has 88K miles, and has sat for awhile, so it's possible a hose or seal has split/cracked.
I am just looking for a starting point.
Thanks!
Shawn
Pro
Joined: Sep 2012
Posts: 610
Likes: 12
From: Seattle Wa
The coolant lines are notorious for leaking. They usually split where the rubber and metal meet. I replaced mine with 1/2in rubber trans coolant lines, and then found the next leak, and so on, and so on. Now this week I just got another coming from the passenger side. These motors have really good oil pressure, so as soon as you seal one spot it moves to the next weakest point. h
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 27
Likes: 0
From: CO
Interesting...he said he thought it was the dipstick, and I see the PCV has no hose on it. That wouldn't explain the oil pooling in the original picture though......
Team Owner
Joined: Mar 2012
Posts: 27,118
Likes: 135
From: Montgomery, Alabama
2017 C6 of Year Finalist
Is there oil on the under side of the hood? My '92 started leaking at the front gasket and there was a line of oil that had been thrown up on the under side of the hood. Oil was also in the area shown in your photo.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Pro
Joined: Sep 2012
Posts: 610
Likes: 12
From: Seattle Wa
On mine those are Transmission coolant lines. Not sure if they are different from year to year though. You keep saying its oil, but if it were tranny fluid, it would be red, so Im a bit confused, but on mine I have tranny lines on the passenger side, and oil on the drivers side. You can replace them with rubber, just make sure you use ones for oil. h
Pro
Joined: Sep 2012
Posts: 610
Likes: 12
From: Seattle Wa
Do the lines go into the radiator? If so, they are tranny lines. You might try tightening them, as there isnt many places where they can leak. Check you tranny fluid too, if its leaking that bad, it should be low. h
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 27
Likes: 0
From: CO
They don't go into the radiator. They actually go into what looks like the front steering stabalizer. Now mind you, this is my first vette, and I am still not sure what everything is under the hood. But, from a 4X4 lovers perspective, it looks like they go into the steering stabalizer, or the front axle. (from a 4X4'ers perspective) I know that is NOT what it is, but I am not sure what the line are going into.
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 27
Likes: 0
From: CO
The more I think about this, I am almost convinced it is the transmission lines. That would explain why idling doesn't leak, but when in drive and getting the RPM's up the fluid starts flying!
Racer
Joined: Oct 2012
Posts: 350
Likes: 2
From: Huntsville AL
They don't go into the radiator. They actually go into what looks like the front steering stabalizer. Now mind you, this is my first vette, and I am still not sure what everything is under the hood. But, from a 4X4 lovers perspective, it looks like they go into the steering stabalizer, or the front axle. (from a 4X4'ers perspective) I know that is NOT what it is, but I am not sure what the line are going into.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Your "steering stabilizer" is the steering rack.
I think you might have a leak at the timing chain cover. On my car the outer ring of the harmonic balancer came loose and walked into the timing chain cover and rubbed a hole in it. You can tell if this is your problem by looking at the timing tab on the timing chain cover. The front edge of the harmonic balancer should be about 3/8" in front of the timing tab. Here's a pic (this is not a Corvette, but you get the idea):
This is what a timing chain cover looks like after the harmonic balancer outer ring has walked into it. I sealed the hole with JB Weld about 10 years ago. I just pulled this off because the crankshaft seal was leaking.
I think you might have a leak at the timing chain cover. On my car the outer ring of the harmonic balancer came loose and walked into the timing chain cover and rubbed a hole in it. You can tell if this is your problem by looking at the timing tab on the timing chain cover. The front edge of the harmonic balancer should be about 3/8" in front of the timing tab. Here's a pic (this is not a Corvette, but you get the idea):
This is what a timing chain cover looks like after the harmonic balancer outer ring has walked into it. I sealed the hole with JB Weld about 10 years ago. I just pulled this off because the crankshaft seal was leaking.
Last edited by Cliff Harris; Jul 24, 2013 at 04:43 AM. Reason: Added pic of timing chain cover.
Pro
Joined: Mar 2013
Posts: 628
Likes: 13
From: Indiana
That's odd. I also had an oil leak but never found it. My hose to my PCV valve was collapsed and when I replaced it the oil leak stopped. My FSM states that a bad PCV can cause oil leaks I just don't know where it was coming out. This was a very small leak and as far as I know it never reached the ground but did coat the starter area. My dipstick also kept popping out. Maybe that is where it came from.
Last edited by Klyde; Jul 12, 2013 at 06:23 PM.
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 27
Likes: 0
From: CO
Thank you everyone for the suggestions. I still haven't found the leak, but please keep throwing out ideas!
Question: Can the timing cover be replaced without pulling the engine?
Thanks!
Shawn
Question: Can the timing cover be replaced without pulling the engine?
Thanks!
Shawn