Help! Main Seal Leak Problem
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Joined: May 2002
Posts: 91
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From: Beaverton OR
Help! Main Seal Leak Problem
Hey all,
I have read so much about that these engines (ls1,ls6) engines don't leak oil.
I had H&C package done and about 4-5 months later I noticed oil on the under side of my car. Initially i thought it was from my oil change but then later starting seeing drips of oil on my garage floor. Sure enough it turned out to be a front main seal.
Bought a whole new timing chain cover assembly and had it replaced. While my tuner was in there we changed out to a different pulley. My old pulley had grooves worn in it big time which was deduced to be the problem. (But what would cause that?)
made the replacments, cleaned engine, off I went. This time it only took about 2.5 months and same problem. Drops of oil on the floor and getting increasingly worse. My new pulley was made of aluminum not the harder stuff that the Stock pulley is made of so I think it took quite a bit shorter time to wear the grooves and create the leak again.
So my question is what would cause the main seal to be cutting the grooves ultimately causing the leak that has been plaguing my car for over a year now?
I have read so much about that these engines (ls1,ls6) engines don't leak oil.
I had H&C package done and about 4-5 months later I noticed oil on the under side of my car. Initially i thought it was from my oil change but then later starting seeing drips of oil on my garage floor. Sure enough it turned out to be a front main seal.
Bought a whole new timing chain cover assembly and had it replaced. While my tuner was in there we changed out to a different pulley. My old pulley had grooves worn in it big time which was deduced to be the problem. (But what would cause that?)
made the replacments, cleaned engine, off I went. This time it only took about 2.5 months and same problem. Drops of oil on the floor and getting increasingly worse. My new pulley was made of aluminum not the harder stuff that the Stock pulley is made of so I think it took quite a bit shorter time to wear the grooves and create the leak again.
So my question is what would cause the main seal to be cutting the grooves ultimately causing the leak that has been plaguing my car for over a year now?
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
The seal isn't cutting any grooves - it's a mylar-like thin membrane that rides on the pulley hub. It's too soft to damage even aluminum.
When you say "grooves" - how many are there? How close to the end of the pulley hub are they? How deep are they? Are you running a dual timing chain?
When you say "grooves" - how many are there? How close to the end of the pulley hub are they? How deep are they? Are you running a dual timing chain?
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Joined: May 2002
Posts: 91
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From: Beaverton OR
water carved the grand canyon
it is right where the main seal pinches down. Oh, and the main seal is of course shot as well.
I would say it is 15-20 thousandths deep. Not sure though. Very visible with the naked eye.
Any idea what would cause that?
Melting Slicks
Joined: Jan 2001
Posts: 2,635
Likes: 2
From: Aloha, Oregon
Originally Posted by Patches
The seal isn't cutting any grooves - it's a mylar-like thin membrane that rides on the pulley hub. It's too soft to damage even aluminum.
When you say "grooves" - how many are there? How close to the end of the pulley hub are they? How deep are they? Are you running a dual timing chain?
When you say "grooves" - how many are there? How close to the end of the pulley hub are they? How deep are they? Are you running a dual timing chain?
Patches: the seal is definitely buzzing into the pulley hub as if excessive crankcase pressure pushing out on the front seal, causing excessive/premature wear on the seal and hub of pulley. It actually wore down a groove around the stock pulley hub about 40mils deep, right where the seal rides on the hub. Yes, double roller, but doesnt matter with stock pulley since stock pulley cinches right into proper place regardless of the oil pump shims required to clear the double roller. I have double rollers on all my h/c customer's cars with stock or UD pulley's- no issues. Its as if his crankcase pressure is not relieving adequately. We've tried many variations of PCV setups except going back to strictly stock. We should try that next, of course, but am curious what others have found with the same issue.
Robert
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
Man, Robert, that is strange. Seems like it would have to be substantially high pressures to push that seal foward hard enough to score alum. I was thinking the hub was rubbing the body of the oil pump due to being spaced out but you obviously have that covered. Could you possibly put a pressure gauge inline to see how elevated it is?
I am so careful putting those seals on because they feel so delicate when you touch them. I have a buddy now with a leak as well but his is from the lower timing cover lip due to inadequate RTV on the cover/pan interface.
I'd be really interested to hear what you ultimately determine is the problem.
I am so careful putting those seals on because they feel so delicate when you touch them. I have a buddy now with a leak as well but his is from the lower timing cover lip due to inadequate RTV on the cover/pan interface.
I'd be really interested to hear what you ultimately determine is the problem.
Melting Slicks
Joined: Jan 2001
Posts: 2,635
Likes: 2
From: Aloha, Oregon
yah, Ed, this is an interesting issue to say the least. This is the 2nd new seal to go. Like I said, we'll try piping the stock PCV back in (we had the CH oil separator bulb inline to the intake port, but that made a bunch of noise. now is plumbed to the TB port, not a great PCV pick point). We'll post what we find.
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Joined: May 2002
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From: Beaverton OR
Robert,
Any ideas? Things I can do at home? It seems to be getting worse every time I drive it which makes sense. It is cutting into that aluminum like butta
I would hate to try do another pulley and main seal without addressing what I have going on.
HELP...my car is bleeding all over my driveway and garage.
Any ideas? Things I can do at home? It seems to be getting worse every time I drive it which makes sense. It is cutting into that aluminum like butta
I would hate to try do another pulley and main seal without addressing what I have going on.
HELP...my car is bleeding all over my driveway and garage.
