Coolant In Oil
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
I am about to look for the photos bogus posted but want to point out
that I meant to qualify my statement about #8 cyl gasket failures as
being symptomatic for L98's w/ aluminum heads, prior to '91.
LT1 engines like in your '93 haven't appeared on the radar nearly so
frequently.
Also, I see that Andy describes the failure as affecting #7 (rear driver's
side) in a post I just came across. However, others have written about
#8.
.
that I meant to qualify my statement about #8 cyl gasket failures as
being symptomatic for L98's w/ aluminum heads, prior to '91.
LT1 engines like in your '93 haven't appeared on the radar nearly so
frequently.
Also, I see that Andy describes the failure as affecting #7 (rear driver's
side) in a post I just came across. However, others have written about
#8.
.
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
Unfortunately, they no longer seem to be on his site.
Here is the thread - Might have signs of blown head gasket now.
Stingraynut's '88 had sprung a leak.
.
Drifting
Joined: Sep 2005
Posts: 1,867
Likes: 3
From: Pasadena Maryland
I have heard the term STEAM CLEANED when referring to coolant in the combustion chamber. I imagine that is what you are seeing in the #8 plug. If you take the Heads off try to see how evenly the bolts are torqued. My neighbors Rustang blew a head gasket and one bolt was only hand tight, not a factory engine but from a professional builder. Could had been stretch, bad gasket .....? Again f the heads come off take them to a machine shop and have them checked for flatness, the AL heads can warp easier than iron.
Thread Starter
Le Mans Master
Joined: Nov 2000
Posts: 5,689
Likes: 0
From: Cape Coral, FL 33904
Well, just got done with the leakdown test. Number 8 cylinder looks to be the cause. air was coming out into the coolant overflow tank. all other cylinders held good at 78-79psi with setting the gauge at 80psi.
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Race Director
Joined: May 2006
Posts: 10,691
Likes: 71
From: Phoenix Arizona
When you get the heads off, you'll see deteriation of the steel band around the top of the cylinder on the gasket. You will also notice it on other cylinders. Autozone or any parts store should have the gasket sets, buy the Felpros. The cheaper ones could cause problems, and the more expensive ones aren't needed. They will say you need to replace the bolts, but that is pretty much up to you.
Safety Car
Joined: Jul 2001
Posts: 4,871
Likes: 15
From: Detroit's West Side MI
Is the assumption that the old bolts will have stretched and could provide less of a seal than new ones at the same torque?
Race Director
Joined: May 2006
Posts: 10,691
Likes: 71
From: Phoenix Arizona
Supposidly they are stretched from the factory, and might not hold the torque when re-used. I've talked to alot of builders who say re-use them in a street application. If you use them and have a problem, you have something easy to blame.
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
Picked this up a long time ago off one of the aftermarket websites...
"Unlike a conventional bolt, TTY bolts are tightened beyond their elastic range past their yield point from which the bolt material can recover to its original length, and into the plastic phase of the bolt material. The bolt is permanently stretched and for this reason should not be reused. The reliability of these bolts once stretched is greatly reduced. If they are reused, they are permanently stretched further a second or third time. It is also for this reason why you should never retorque a torque to yield bolt."
Factory Service Manual says to not reuse as well.
FWIW
Pro
Joined: May 2007
Posts: 638
Likes: 1
From: Robesonia Pa
...
"Unlike a conventional bolt, TTY bolts are tightened beyond their elastic range past their yield point from which the bolt material can recover to its original length, and into the plastic phase of the bolt material. The bolt is permanently stretched and for this reason should not be reused. The reliability of these bolts once stretched is greatly reduced. If they are reused, they are permanently stretched further a second or third time. It is also for this reason why you should never retorque a torque to yield bolt."
Factory Service Manual says to not reuse as well.
FWIW
"Unlike a conventional bolt, TTY bolts are tightened beyond their elastic range past their yield point from which the bolt material can recover to its original length, and into the plastic phase of the bolt material. The bolt is permanently stretched and for this reason should not be reused. The reliability of these bolts once stretched is greatly reduced. If they are reused, they are permanently stretched further a second or third time. It is also for this reason why you should never retorque a torque to yield bolt."
Factory Service Manual says to not reuse as well.
FWIW
and only a few dollars for insurance the bolts are good! Do it right the first time or pay for it later
Advanced
Joined: Nov 2005
Posts: 54
Likes: 1
From: San Jose California
Don't ever reuse the old bolts, you are just asking for trouble. 
Head gasket set: FelPro p/n: HS9966PT2 - Retail about $179.95
Head bolt set (times 2): FelPro p/n:ES72856 - Retail about $29.95 for each head.
The head gasket set should have pretty much all the gaskets you need to complete the job, including intake, exhaust, etc.
Remember, you need 2 sets of head bolts, one set for each head.
