Oil Leak
Thread Starter
Instructor
Joined: Sep 2009
Posts: 192
Likes: 0
From: Yukon OK
Oil Leak
So I was changing the oil on my 1986 Vette for the first time and I tried to fix a very small oil leak that it had by tightening some bolts on the undercarrage around where the leak seemed to be coming from. Now the leak has gotten worse.
In about 3-4 hours it leaked oil about the size of my palm.
I'm not sure the name of the part that the leak originated from but it is located about 6-8 Inches from the oil drain plug towards the rear of the car. Any ideas on what it is and how I made it worse? I'm pretty new to working on cars (GM especially) so I probably screwed somthing up
In about 3-4 hours it leaked oil about the size of my palm. I'm not sure the name of the part that the leak originated from but it is located about 6-8 Inches from the oil drain plug towards the rear of the car. Any ideas on what it is and how I made it worse? I'm pretty new to working on cars (GM especially) so I probably screwed somthing up
Team Owner
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The only I could think is a cork gasket. You over-tight it.
You have to do "surgery" my friend. You need a new oil pan gasket and all the other extras that come with it. I could be wrong
.
You have to do "surgery" my friend. You need a new oil pan gasket and all the other extras that come with it. I could be wrong
.
Racer
Joined: Sep 2007
Posts: 438
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From: Grandville, Michigan
I agree with PLRX. The gasket probably was deteriated and has to be replaced. Tightening only split it open more.
Pro
Joined: Feb 2009
Posts: 589
Likes: 1
From: PA
I'm wondering if he's talking 6 to 8 inches horizontally (towards the rear of the car). Maybe he tightened up a transmission pan bolt and split that gasket?????
Hey Iglo, what size socket were you using on this bolt? This might give a us clue what you were tightening.
Hey Iglo, what size socket were you using on this bolt? This might give a us clue what you were tightening.
Last edited by 65747785; Oct 28, 2009 at 05:28 PM.
Thread Starter
Instructor
Joined: Sep 2009
Posts: 192
Likes: 0
From: Yukon OK
After further review I definitely tightened the Transmission pan. I'm 99% positive that oil is leaking and not tranny fluid. There is an aluminum plate between the oil pan and the transmission pan and that is where the oil accumulates. I checked the valve cover gaskets and one side is leaking but it doesn't appear to be nearly enough to be the leak I'm looking for. I called a local vette mechanic today and he is going to put it on a lift monday and try to figure out whats leaking. He said that he'd look at it for free so I figure thats a good deal
Also I asked what he would charge to change the rear seal if that was the problem and he said about $300. Does that sound about right price wise? I really don't think I could handle that myself and it seems pretty reasonable considering the amount of work involved.
Pro
Joined: Feb 2009
Posts: 589
Likes: 1
From: PA
Yep, sounds like the rear seal. Chevy engines are notorious for that. It's not a hard job, but time consuming. He can do this job with the engine in the car, he probably told you that.
I guess $300 is good, I don't know because I do these things myself. Maybe call some other shops just to get a price. This will let ya know if his $300 is a good deal. Don't call the Chevorlet dealer as they're very high priced on repairs.
It all depends on how bad the leak is. If it's not that big, leave it alone for a while. But don't park on someone's nice new driveway.
I guess $300 is good, I don't know because I do these things myself. Maybe call some other shops just to get a price. This will let ya know if his $300 is a good deal. Don't call the Chevorlet dealer as they're very high priced on repairs.
It all depends on how bad the leak is. If it's not that big, leave it alone for a while. But don't park on someone's nice new driveway.
Pro
Joined: Feb 2009
Posts: 589
Likes: 1
From: PA
Oh, I wanted to say, you can change your trans pan gasket and filter inside, it's a pretty easy job. Just have a big catch bucket underneath the pan when loosening the bolts, then seperating the pan from the transmission. Once you get past the dirty work (trans fluid dripping) then it's clear sailing the rest of the way. Make sure the mating surface (gasket area) of the trans case is free of fluid.
A couple tips. Once you clean the pan, eyeball for flatness around the pan where the bolt holes are. If you see some that are raised, smack em with a hammer on a flat surface (work bench or...) to make em level. You might want to paint the outside of the pan too.
Use Permatex #2 on both sides of the new gasket and a dab on all the bolts. It'll never leak again.
A couple tips. Once you clean the pan, eyeball for flatness around the pan where the bolt holes are. If you see some that are raised, smack em with a hammer on a flat surface (work bench or...) to make em level. You might want to paint the outside of the pan too.
Use Permatex #2 on both sides of the new gasket and a dab on all the bolts. It'll never leak again.
Last edited by 65747785; Oct 29, 2009 at 11:47 AM.
Cruising
Joined: Jan 2009
Posts: 14
Likes: 0
From: Indianapolis Indiana
Lou dog, $300. is not bad to replace rear main, if I did it, I'd charge you $500. (just kidding)
Now this is just the beginng, your first of several projects you will endure over the years because it becomes additive to perfect this one and in time you will be making more money and be able to have more exspensive ones. Most are money pits but it's fun and rewarding in the long run.
Need any help, give a call.
love ya,
grandpa
Now this is just the beginng, your first of several projects you will endure over the years because it becomes additive to perfect this one and in time you will be making more money and be able to have more exspensive ones. Most are money pits but it's fun and rewarding in the long run.
Need any help, give a call.
love ya,
grandpa
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Melting Slicks
Joined: Nov 2005
Posts: 2,736
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From: WAY UPSTATE NY
Oh, I wanted to say, you can change your trans pan gasket and filter inside, it's a pretty easy job. Just have a big catch bucket underneath the pan when loosening the bolts, then seperating the pan from the transmission. Once you get past the dirty work (trans fluid dripping) then it's clear sailing the rest of the way. Make sure the mating surface (gasket area) of the trans case is free of fluid.
A couple tips. Once you clean the pan, eyeball for flatness around the pan where the bolt holes are. If you see some that are raised, smack em with a hammer on a flat surface (work bench or...) to make em level. You might want to paint the outside of the pan too.
Use Permatex #2 on both sides of the new gasket and a dab on all the bolts. It'll never leak again.
A couple tips. Once you clean the pan, eyeball for flatness around the pan where the bolt holes are. If you see some that are raised, smack em with a hammer on a flat surface (work bench or...) to make em level. You might want to paint the outside of the pan too.
Use Permatex #2 on both sides of the new gasket and a dab on all the bolts. It'll never leak again.
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
Bolts go into blind holes, so goop on them will prevent the bolts from sealing, as you cannot get an accurate torque reading.