big oil leak!
Thread Starter
Pro
Joined: Aug 2006
Posts: 682
Likes: 1
From: SpringHill florida
big oil leak!
ive posted about this before but am now getting to work on it tonight,where is the most common oil leak to happen in the front of the motor,there's oil all over the idler pulley,so i think it could be the timing chain gasket,i need help!
Thread Starter
Pro
Joined: Aug 2006
Posts: 682
Likes: 1
From: SpringHill florida
Melting Slicks
Joined: Jun 2002
Posts: 2,705
Likes: 30
From: Chesapeake Beach Maryland
2015 C5 of Year Finalist
OK - I am in the middle of the "oil sieve" syndrome repair. Mine also had an oil leak that progressively got worse until I noticed larger and larger spots of oil. The underside of the front of the motor, oil pan, and behind was pretty much covered.
I haven't identified any specific leak location, but it seems it was leaking from the water pump shaft seal, the timing cover gasket, oil pan gasket and probably the intake gasket as well. The car has ~150k miles and needs a little TLC.
I know you don't want to hear this, but it is probably a combination of the intake manifold and the timing cover. Intake gasket won't be a major problem, but the timing cover gasket can be a major undertaking if you are not the wrenching type. I think the Chevy dealership would charge at least $1500 for this job, and wouldn't spend the time cleaning everything up that I am doing along the way.
Good Luck - Feel free to ask questions, as I am well into this job, and just doing a little bit every night or two. Tonight I finally got to the oil pan and it is down, awaiting to remove the timing cover tomorrow.
Cheers
I haven't identified any specific leak location, but it seems it was leaking from the water pump shaft seal, the timing cover gasket, oil pan gasket and probably the intake gasket as well. The car has ~150k miles and needs a little TLC.
I know you don't want to hear this, but it is probably a combination of the intake manifold and the timing cover. Intake gasket won't be a major problem, but the timing cover gasket can be a major undertaking if you are not the wrenching type. I think the Chevy dealership would charge at least $1500 for this job, and wouldn't spend the time cleaning everything up that I am doing along the way.
Good Luck - Feel free to ask questions, as I am well into this job, and just doing a little bit every night or two. Tonight I finally got to the oil pan and it is down, awaiting to remove the timing cover tomorrow.
Cheers
Thread Starter
Pro
Joined: Aug 2006
Posts: 682
Likes: 1
From: SpringHill florida
OK - I am in the middle of the "oil sieve" syndrome repair. Mine also had an oil leak that progressively got worse until I noticed larger and larger spots of oil. The underside of the front of the motor, oil pan, and behind was pretty much covered.
I haven't identified any specific leak location, but it seems it was leaking from the water pump shaft seal, the timing cover gasket, oil pan gasket and probably the intake gasket as well. The car has ~150k miles and needs a little TLC.
I know you don't want to hear this, but it is probably a combination of the intake manifold and the timing cover. Intake gasket won't be a major problem, but the timing cover gasket can be a major undertaking if you are not the wrenching type. I think the Chevy dealership would charge at least $1500 for this job, and wouldn't spend the time cleaning everything up that I am doing along the way.
Good Luck - Feel free to ask questions, as I am well into this job, and just doing a little bit every night or two. Tonight I finally got to the oil pan and it is down, awaiting to remove the timing cover tomorrow.
Cheers
I haven't identified any specific leak location, but it seems it was leaking from the water pump shaft seal, the timing cover gasket, oil pan gasket and probably the intake gasket as well. The car has ~150k miles and needs a little TLC.
I know you don't want to hear this, but it is probably a combination of the intake manifold and the timing cover. Intake gasket won't be a major problem, but the timing cover gasket can be a major undertaking if you are not the wrenching type. I think the Chevy dealership would charge at least $1500 for this job, and wouldn't spend the time cleaning everything up that I am doing along the way.
Good Luck - Feel free to ask questions, as I am well into this job, and just doing a little bit every night or two. Tonight I finally got to the oil pan and it is down, awaiting to remove the timing cover tomorrow.
Cheers
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Sythetic or Not?
My car leaks oil but that's how I know I still have oil in there.....if it stops leaking I'll begin to worry about it.
From my experience large leaks usually occur from the crank seals -- look at the rear main seal or the timing cover crank seal. These types of leaks are very common. A little oil can go a long way. It might not hurt to do a compression test to ensure that's not a "blow by" gremlin in there. If you have a compression "blow by" problem new seals won't help for long.
Let me ask you this....have you switched over to sythenic motor oil?
If you've noticed that your car is leaking more oil than usual since the switch then that's your problem: "ultra thin synthetic motor oil". Synthetic oils can make loose seals leak ~ if you insist on using sythetics use a heavier wieght to slow the leaks down a bit.
Earlier model engine seals were not designed to stand up to sythetic oils. If you entend on using synthic oil get an approved seal intended for that use.
Good luck!
From my experience large leaks usually occur from the crank seals -- look at the rear main seal or the timing cover crank seal. These types of leaks are very common. A little oil can go a long way. It might not hurt to do a compression test to ensure that's not a "blow by" gremlin in there. If you have a compression "blow by" problem new seals won't help for long.
Let me ask you this....have you switched over to sythenic motor oil?
If you've noticed that your car is leaking more oil than usual since the switch then that's your problem: "ultra thin synthetic motor oil". Synthetic oils can make loose seals leak ~ if you insist on using sythetics use a heavier wieght to slow the leaks down a bit.
Earlier model engine seals were not designed to stand up to sythetic oils. If you entend on using synthic oil get an approved seal intended for that use.
Good luck!
Team Owner
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
Cruise-In IV Veteran
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You can by a U/V light leak detection kit at most auto parts stores. That'll help you positively ID the leaks.
Thread Starter
Pro
Joined: Aug 2006
Posts: 682
Likes: 1
From: SpringHill florida
hopefully i'll be able to throw things back together in time,i feel like im on one of those tv shows where they have a deadline!
Le Mans Master
Joined: Oct 2004
Posts: 5,841
Likes: 19
From: CLT, North Carolina
Most likely cause is the RTV sealant applied between both ends of the intake manifold and the block china rails. Whatever RTV they originally used deteriorates with age and loses its ability to seal and has to be replaced. Second likely cause is the crankshaft hub seal or the waterpump driveshaft seal. If the car has around 100K miles it is likely these parts have wear grooves which will need to be addressed in addition to installing new seals. Another likely cause for LT-1 oil leaks is the Oil filter adapter "O" ring. It takes a set and hardens and leaks. My 96 project car leaked so bad from all these areas at the time I got it that oil was dripping off the mufflers and rear end housing. I have posted in other threads about that.
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Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
hub groove
they sell a hub groove cover that is stainless steel that you tap onto the harmonic balancer hub. it replaces the worn area, and makes the seal tighter and lasts longer. you just have to lube it when you install it, or it will overheat the seal, and may leak prematurely.
Safety Car
Joined: Aug 2006
Posts: 4,147
Likes: 452
From: Port St. Lucie West Florida
they sell a hub groove cover that is stainless steel that you tap onto the harmonic balancer hub. it replaces the worn area, and makes the seal tighter and lasts longer. you just have to lube it when you install it, or it will overheat the seal, and may leak prematurely.
