Bad head gasket new 347 build

ebowie

Member
Oct 16, 2018
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A bad alternator caused my serpentine belt to come off on my new 347 build, only have 100 miles on it. It got hot and my drivers side head gasket is leaking. Is it ok to just replace the bad gasket or do I rip both heads off and start over. Thoughts and opinions
 
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95BlueStallion

My assy trans to myself
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Feb 22, 2007
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Take the head off the bad side, observe the cylinder walls on that side. If they still look nice and smooth, install new gasket and roll with it. If you have scoring from lack of oil lube while it was running, then you know it needs to come back apart.
 

mikestang63

SN Certified Technician
Aug 27, 2012
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do a leak down or compression test on all cylinders to confirm, but I never replace just one side as a precaution. If you are already tearing it down might as well do both sides. Check the heads and deck for being square. I have used the 9333PT1 head gaskets with good success and APR head studs
 
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2Blue2

will be trying this sex one when I can find it
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Do you know what head gasket was used?

Should be matched sets. No brand ‘A’ one side brand’B’ other type stuff.
 

Gs1987GT

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Sep 25, 2019
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Sorry for your troubles.....Coming apart that far, I'm in the do it once and ensure it's right....do both and be done. Even if its fine initially, if the non leaking side is weak now from the heat it could fail soon after and you'll be tearing it apart for a 3rd time. No thanks.
 

revhead347

Apparently my ex-husband made that mistake.
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Ok, there is a possibility that the reason the head gasket leaked is because the engine got hot enough to warp the heads. You want to check the heads to make sure they are not warped when you change the gaskets. It's a simple procedure. If the heads are warped, it usually just requires mild resurfacing that any engine shop can do. Unfortunately engine machine shops work in a different dimension and understanding of time.

Kurt
 
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revhead347

Apparently my ex-husband made that mistake.
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So true, but when I was young there were a dozen local machine shops.... Now there is one......
Even when there were a dozen of them it took months to get any engine work done. The machine shops became obsolete just like the film developers. It's the fact that modern cars have so few engine mechanical failures requiring machine work before doing such work exceeds the value of the vehicle, there isn't much demand for it. It's not a conspiracy.

Kurt
 

limp

wrap a little cheese around it and its a done
Oct 4, 2020
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I guess it depends on where you're at (OR). I've been at 2wks and 6mo+ turn this year on 2 sets of heads.
:perha;ps I didn't state my comment correctly..... I was talking about 30-40 years ago when there were many maching shops around, unlike today where you are lucky to find one in a 50 mile radius with months of wait time for any work to be completed....
 
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