Harmonic balancer seal, LT1
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Intermediate
Joined: Jul 2011
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Harmonic balancer seal, LT1
I replaced the opti in my 93 and noticed a new oil leak afterward. I retraced my steps and I was very careful to tighten the torqs for the opti. The water pump wouldn't leak oil so i"m OK there.
So I'm thinking that the harmonic balancer seal might be leaking. I always replace a rear main seal for a clutch or trans work just cause it's accessible and it's good insurance against a future leak.
I never really thought about that with the harmonic balancer. Should I expect that after removing it once the seal will have gone bad? What's it take to replace it?
So I'm thinking that the harmonic balancer seal might be leaking. I always replace a rear main seal for a clutch or trans work just cause it's accessible and it's good insurance against a future leak.
I never really thought about that with the harmonic balancer. Should I expect that after removing it once the seal will have gone bad? What's it take to replace it?
Instructor
Joined: Aug 2010
Posts: 200
Likes: 1
From: Somers N.Y.
I replaced the opti in my 93 and noticed a new oil leak afterward. I retraced my steps and I was very careful to tighten the torqs for the opti. The water pump wouldn't leak oil so i"m OK there.
So I'm thinking that the harmonic balancer seal might be leaking. I always replace a rear main seal for a clutch or trans work just cause it's accessible and it's good insurance against a future leak.
I never really thought about that with the harmonic balancer. Should I expect that after removing it once the seal will have gone bad? What's it take to replace it?
So I'm thinking that the harmonic balancer seal might be leaking. I always replace a rear main seal for a clutch or trans work just cause it's accessible and it's good insurance against a future leak.
I never really thought about that with the harmonic balancer. Should I expect that after removing it once the seal will have gone bad? What's it take to replace it?
Thread Starter
Intermediate
Joined: Jul 2011
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It wouldn't matter if I cleaned the leak area. I can't see what's going on in there anyway, too much stuff in too little space.
It looks like I can get the balancer off without taking the water pump off. What's it take to get the seal in and out? Also, I can't remember if there was a gasket with the opti. Is there supposed to be one?
It looks like I can get the balancer off without taking the water pump off. What's it take to get the seal in and out? Also, I can't remember if there was a gasket with the opti. Is there supposed to be one?
Instructor
Joined: Aug 2010
Posts: 200
Likes: 1
From: Somers N.Y.
It wouldn't matter if I cleaned the leak area. I can't see what's going on in there anyway, too much stuff in too little space.
It looks like I can get the balancer off without taking the water pump off. What's it take to get the seal in and out? Also, I can't remember if there was a gasket with the opti. Is there supposed to be one?
It looks like I can get the balancer off without taking the water pump off. What's it take to get the seal in and out? Also, I can't remember if there was a gasket with the opti. Is there supposed to be one?
Team Owner
Joined: Aug 2005
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From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
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2017 C4 of Year
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St. Jude Donor '09 thru '20
Did you install a new water pump drive oil seal?
If you did, likely your oil leak comes from it.
If you did, likely your oil leak comes from it.
Thread Starter
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The water pump drive seems like it's probably it, at least I'd rather replace that than the balancer seal. I took the serpentine belt and tensioner off for the opti but it looks like I might be able to get the waterpump off without disturbing those things. Please let me know if that's true and also what it takes to get the seal in and out.
Team Owner
Joined: Aug 2005
Posts: 34,988
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From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
2018 Corvette of Year Finalist
2017 C4 of Year
2016 C7 of Year Finalist
St. Jude Donor '09 thru '20
Thread Starter
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Joined: Jul 2011
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Nothing I like better than re-doing the same job I hated the first time because I forgot something.
Looks like the whole mess has to come apart again for the seals. My knuckles just started bleeding when they heard about it.
As for parts, I've got the water pump gaskets, the thermostat seems to have a rubber seal. I can't figure out whether there's a paper gasket between the flange and the casting.
I'll need an opti seal, a waterpump spline seal, two o rings and I'll have to find that tool to keep the seal from bending backwards.
Can you confirm that's it?
Looks like the whole mess has to come apart again for the seals. My knuckles just started bleeding when they heard about it.
As for parts, I've got the water pump gaskets, the thermostat seems to have a rubber seal. I can't figure out whether there's a paper gasket between the flange and the casting.
I'll need an opti seal, a waterpump spline seal, two o rings and I'll have to find that tool to keep the seal from bending backwards.
Can you confirm that's it?
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Team Owner
Joined: Aug 2005
Posts: 34,988
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From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
2018 Corvette of Year Finalist
2017 C4 of Year
2016 C7 of Year Finalist
St. Jude Donor '09 thru '20
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St. Jude Donor '12
No paper gasket for the thermostat. The rubber seal is all there is.
For the waterpump oil seal installation tool a whiteboard marker makes a great install tool. There are posts all over the internet with the dimensions to cut it down.
Your list and the modified whiteboard marker should do it.
For the waterpump oil seal installation tool a whiteboard marker makes a great install tool. There are posts all over the internet with the dimensions to cut it down.
Your list and the modified whiteboard marker should do it.
Thread Starter
Intermediate
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Thanks guys, has anyone used a 1/2 inch drive impact wrench with a swivel extension to get at the balancer bolts? Last time I used a bolt through one of the holes to immobilize it and a breaker bar to turn the bolts. It would be $50 well spent to get the air wrench but I don't know if there's enough room in the compartment to get at the bolts.
Pro
Joined: Nov 2008
Posts: 616
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From: Cocoa Beach FL
Hey I'm doing this exact same thing cause I had an oil leak after opti and water pump install! Glad to see I not the only one, and won't be the last either I bet. Lol fun fun fun. But I am at tje point where I have had so many c4s I can't get it all apart in less than an hour and will put it all back together I'm tje morning and that's just saying that I was dumb enough to have to do this more than once! 
Team Owner
Joined: Feb 2006
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From: San Antonio Texas
When I did mine, I had a little wear ring on the hub shaft where it rubs on the seal. On advice from another builder I got a "hub seal saver". It's a little slip-on sleeve that goes over the seal area. It looks like the lower end of a redBull can that has had the top cut off. It's very thin but makes the hub shaft smooth and even again. You heat it up in the oven and slip it over a cold hub shaft. A lot cheaper than getting a new hub.
