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Bad head gasket new 347 build

  • Thread starter Thread starter ebowie
  • Start date Start date Jul 27, 2022

ebowie

5 Year Member
Oct 16, 2018
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Okee Wisconsin
Jul 27, 2022
#1
  • Jul 27, 2022
  • #1
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
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
Jul 27, 2022
#2
  • Jul 27, 2022
  • #2
That new I take a chance on replacing the bad gasket
JMO
 

95BlueStallion

My assy trans to myself
15 Year Member
Feb 22, 2007
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Cedar Rapids, Iowa
Jul 27, 2022
#3
  • Jul 27, 2022
  • #3
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.
 

manicmechanic007

5 Year Member
Sep 26, 2017
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Roy, Utah
Jul 28, 2022
#4
  • Jul 28, 2022
  • #4
I would replace them both
 
Reactions: Gs1987GT

mikestang63

SN Certified Technician
Aug 27, 2012
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In the garage
Jul 29, 2022
#5
  • Jul 29, 2022
  • #5
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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Patrick Sullivan

Member
Jul 1, 2022
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Aurora CO
Jul 30, 2022
#6
  • Jul 30, 2022
  • #6
I am an Irishman relative to Murphy & his law. I'd do both.. just cuz .
 

2Blue2

will be trying this sex one when I can find it
Mod Dude
Mar 5, 2019
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Oahu
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#7
  • Jul 30, 2022
  • #7
Do you know what head gasket was used?

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

Gs1987GT

Active Member
Sep 25, 2019
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MidAtlantic
Jul 31, 2022
#8
  • Jul 31, 2022
  • #8
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.
 

Bullitt347

I have been doing it wrong this whole time
15 Year Member
Mar 23, 2007
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Middle of Maine
Jul 31, 2022
#9
  • Jul 31, 2022
  • #9
Do both.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
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#10
  • Aug 1, 2022
  • #10
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
 
Reactions: General karthief

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
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Florida
Aug 1, 2022
#11
  • Aug 1, 2022
  • #11
revhead347 said:
Unfortunately engine machine shops work in a different dimension and understanding of time.

Kurt
Click to expand...
So true, but when I was young there were a dozen local machine shops.... Now there is one......
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
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#12
  • Aug 1, 2022
  • #12
limp said:
So true, but when I was young there were a dozen local machine shops.... Now there is one......
Click to expand...
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
5 Year Member
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Aug 2, 2022
#13
  • Aug 2, 2022
  • #13
revhead347 said:
Even when there were a dozen of them it took months to get any engine work done.

Kurt
Click to expand...
I would have to say that was not my experience... A few days at the most a week...... Maybe you lived in a larger town and they were busier?
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
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Acworth, GA
Aug 2, 2022
#14
  • Aug 2, 2022
  • #14
limp said:
I would have to say that was not my experience... A few days at the most a week...... Maybe you lived in a larger town and they were busier?
Click to expand...

Yeah, Florida. Massive back log for engine work.

Kurt
 

limp

wrap a little cheese around it and its a done
5 Year Member
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Aug 3, 2022
#15
  • Aug 3, 2022
  • #15
revhead347 said:
Yeah, Florida. Massive back log for engine work.

Kurt
Click to expand...
My Experiences were in Oregon.......
 
B

bwest

Member
Oct 25, 2005
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9
18
Aug 9, 2022
#16
  • Aug 9, 2022
  • #16
limp said:
My Experiences were in Oregon.......
Click to expand...
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.
 

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
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Aug 10, 2022
#17
  • Aug 10, 2022
  • #17
bwest said:
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.
Click to expand...
erha;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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