Permatex for sure.
Head gasket leak
Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
Head gasket leak
Hello, I have AFR 195 Heads that I just put on to a stock L98 short block, I used a fel pro 1094 that was suggested to me with 0.015" thickness and my deck height was 0.024", making optimal quench at 0.039".
I almost finished assembling it and was putting in the antifreeze using an evacuator and fill tool when I noticed it wouldn't hold vacuum.
I put a pressure tester on it and located a lot of leaks around the intake, and then I filled it with water and pressurized the system and it is leaking out of both sides of the head, on both heads, right at the gasket.
So, what gasket should I get now to replace this one so it doesn't leak? I'm very pissed off at this point because it was $30 bucks for each head gasket, plus $30 for a set of intake gaskets.
I need something that won't leak but will be pretty decent for quench.
Thanks.
I almost finished assembling it and was putting in the antifreeze using an evacuator and fill tool when I noticed it wouldn't hold vacuum.
I put a pressure tester on it and located a lot of leaks around the intake, and then I filled it with water and pressurized the system and it is leaking out of both sides of the head, on both heads, right at the gasket.
So, what gasket should I get now to replace this one so it doesn't leak? I'm very pissed off at this point because it was $30 bucks for each head gasket, plus $30 for a set of intake gaskets.
I need something that won't leak but will be pretty decent for quench.
Thanks.
Race Director
Joined: Apr 2003
Posts: 17,697
Likes: 1,666
From: moraga ca
Are these new heads or are they used. If used, they might have to be milled a few thousanths to make sure they are flat. I always use a couple coats of Permatex Copper Coat on both sides of my head gaskets and never have had a problem. I also use a small bottle of K-seal stop leak after having my heads off. Good stuff.
Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
Okay, well I talked to one of my buddies who used to build hot rods.
He said that I shouldn't use the Fel Pro 1094 for street use.
He said I should look into a graphite gasket because it expands and contracts better.
I wasn't able to find a graphite gasket, but I did find one made of composite.
He said it was okay to use, but I just want to get some more input. Is a composite gasket okay to use with my build?
And another thing, this gasket is 0.028", which would make my quench area 0.052".
He said that quench on a street application is not as important as it is for drag applications. He said that should be fine for up to like 600 horsepower.
I read online that quench area stops being effective at around 0.060" - 0.080".
Is my quench going to be okay with 0.052" instead of 0.039" which it was before?
It also is lowering my compression from 10.3:1 to 9.99:1
I plan on running 93 octane.
Thanks for the help.
He said that I shouldn't use the Fel Pro 1094 for street use.
He said I should look into a graphite gasket because it expands and contracts better.
I wasn't able to find a graphite gasket, but I did find one made of composite.
He said it was okay to use, but I just want to get some more input. Is a composite gasket okay to use with my build?
And another thing, this gasket is 0.028", which would make my quench area 0.052".
He said that quench on a street application is not as important as it is for drag applications. He said that should be fine for up to like 600 horsepower.
I read online that quench area stops being effective at around 0.060" - 0.080".
Is my quench going to be okay with 0.052" instead of 0.039" which it was before?
It also is lowering my compression from 10.3:1 to 9.99:1
I plan on running 93 octane.
Thanks for the help.
Safety Car
Joined: Jan 2004
Posts: 3,783
Likes: 15
From: Northern California
Wait,...
Were you the one who used an abrasive disc grinder to clean the old gasket material off the block?...
If so, The block is probably warped causing all the leaks...
Edit:
You are the one, I found your post.
http://forums.corvetteforum.com/c4-t...questions.html
.
Were you the one who used an abrasive disc grinder to clean the old gasket material off the block?...
If so, The block is probably warped causing all the leaks...
Edit:
You are the one, I found your post.
http://forums.corvetteforum.com/c4-t...questions.html
.
Last edited by GKK; Mar 4, 2014 at 07:57 PM.
Drifting
Joined: Jul 2009
Posts: 1,257
Likes: 98
From: Ashland PA
2021 C4 of the Year - Modified Finalist
Did you you put thread sealer on all the bolts that require it and did you put rtv on the intake gasket around the coolant passages if not your head may be leaking from those spots.
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Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
I think that may be the reason why it leaked. But I think the new gasket I have will be better because as I'm told the 1094 is meant for engines that are torn down frequently.
Only question though that concerns me, since I used an abrasive disc on the deck, it is all over the internet that the material gets into the rings and into the oil and isn't filtered by the filter and causes premature bearing failure.
I used an air hose to blow out all the dirt and stuff from the rings, and I got a lot of what was in there.
Do you guys think that my bearings will fail? If so, what can I do to stop that from happening?
Thanks.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
You may have a problem with removing bolts where you applied the red threadlocker. Heat will be needed to loosen that stuff.
You shouldn't have a big issue with anything getting past the rings and into the oil. The oil filter will trap that stuff. Definitely do an oil change and replace the filter ASAP.
But as mentioned, your earlier use of a cookie (and I assume an air grinder) on the block deck may be the big problem. If a head gasket (regardless of which one it is) won't seal, then don't worry about quench area, compression ratio, or bearing life as you will be looking at removing the engine and getting the block deck machined.
Is there a tool rental place or maybe an AutoZone store where you can rent a machinist's straightedge? That will tell you if the block surface is straight. And there is nothing wrong with the FelPro 1094 gasket.
You shouldn't have a big issue with anything getting past the rings and into the oil. The oil filter will trap that stuff. Definitely do an oil change and replace the filter ASAP.
But as mentioned, your earlier use of a cookie (and I assume an air grinder) on the block deck may be the big problem. If a head gasket (regardless of which one it is) won't seal, then don't worry about quench area, compression ratio, or bearing life as you will be looking at removing the engine and getting the block deck machined.
Is there a tool rental place or maybe an AutoZone store where you can rent a machinist's straightedge? That will tell you if the block surface is straight. And there is nothing wrong with the FelPro 1094 gasket.
Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
No.
I got the bolts out. There wasn't any sparks when I used the cookie. And I really didn't want to pull the motor out and have it decked, because then while I have it out I'd have it rebuilt, but I don't have the money for that right now. And if I was to have it rebuilt I would go to a 383. And I really don't have money for that either.
The surface feels smooth, and you can't grab a finger nail on anything.
Also, I had drained the oil before I cleaned the deck, and it already has new oil and filter. So now I have to change it again, plus I'll have to order more ZDDP additive. :/
You may have a problem with removing bolts where you applied the red threadlocker. Heat will be needed to loosen that stuff.
You shouldn't have a big issue with anything getting past the rings and into the oil. The oil filter will trap that stuff. Definitely do an oil change and replace the filter ASAP.
But as mentioned, your earlier use of a cookie (and I assume an air grinder) on the block deck may be the big problem. If a head gasket (regardless of which one it is) won't seal, then don't worry about quench area, compression ratio, or bearing life as you will be looking at removing the engine and getting the block deck machined.
Is there a tool rental place or maybe an AutoZone store where you can rent a machinist's straightedge? That will tell you if the block surface is straight. And there is nothing wrong with the FelPro 1094 gasket.
You shouldn't have a big issue with anything getting past the rings and into the oil. The oil filter will trap that stuff. Definitely do an oil change and replace the filter ASAP.
But as mentioned, your earlier use of a cookie (and I assume an air grinder) on the block deck may be the big problem. If a head gasket (regardless of which one it is) won't seal, then don't worry about quench area, compression ratio, or bearing life as you will be looking at removing the engine and getting the block deck machined.
Is there a tool rental place or maybe an AutoZone store where you can rent a machinist's straightedge? That will tell you if the block surface is straight. And there is nothing wrong with the FelPro 1094 gasket.
The surface feels smooth, and you can't grab a finger nail on anything.
Also, I had drained the oil before I cleaned the deck, and it already has new oil and filter. So now I have to change it again, plus I'll have to order more ZDDP additive. :/
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 112
From: Michigan
Sounds like you got lucky on the bolts. I think you'll be fine with the .028 gasket if the heads weren't clean up with the disc. I know of a engine that the block and iron heads where both cleaned up with disc and it didn't leak with a .039 gasket. Far as bearings, I'd start saving for that 383.
edit: Well I know when I use red thread lock both surfaces are clean and oil free, so it can do it's job.
edit: Well I know when I use red thread lock both surfaces are clean and oil free, so it can do it's job.
Last edited by BOOT77; Mar 5, 2014 at 04:54 PM.
Melting Slicks
Joined: May 2010
Posts: 2,082
Likes: 3
From: Conowingo Maryland
using a grinder of any sort on mateing surfaces you are asking for trouble as said by C4crusier you need to get a straight edge and go over the block with a fine tooth comb. There are a couple of ways in doing it but I like haveing a light on one side and see if it shines thru as you place and move the edge at different locations. Also you want thread sealeant not locker.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
No.
I got the bolts out. There wasn't any sparks when I used the cookie. And I really didn't want to pull the motor out and have it decked, because then while I have it out I'd have it rebuilt, but I don't have the money for that right now. And if I was to have it rebuilt I would go to a 383. And I really don't have money for that either.
The surface feels smooth, and you can't grab a finger nail on anything.
Also, I had drained the oil before I cleaned the deck, and it already has new oil and filter. So now I have to change it again, plus I'll have to order more ZDDP additive. :/
I got the bolts out. There wasn't any sparks when I used the cookie. And I really didn't want to pull the motor out and have it decked, because then while I have it out I'd have it rebuilt, but I don't have the money for that right now. And if I was to have it rebuilt I would go to a 383. And I really don't have money for that either.
The surface feels smooth, and you can't grab a finger nail on anything.
Also, I had drained the oil before I cleaned the deck, and it already has new oil and filter. So now I have to change it again, plus I'll have to order more ZDDP additive. :/
Why do you want/need ZDDP oil additive? I can see it when breaking in a new engine, but for amount of miles on your motor, just use a good grade of full synthetic oil. That should be all you need.
Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
Cookies like the ones you used are a plastic material so there would be no reason to look for any sparks. Smoothness of the deck surface really doesn't matter. How straight the deck is does. You really need to check that. If the deck fails that check, be prepared to pull the engine as the chances are you will not get a good seal that will last any length of time.
Why do you want/need ZDDP oil additive? I can see it when breaking in a new engine, but for amount of miles on your motor, just use a good grade of full synthetic oil. That should be all you need.
Why do you want/need ZDDP oil additive? I can see it when breaking in a new engine, but for amount of miles on your motor, just use a good grade of full synthetic oil. That should be all you need.