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Head bolts leaking coolant!!!!

  • Thread starter Thread starter Spook302
  • Start date Start date Apr 1, 2007
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Spook302

Member
Jun 21, 2005
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Durango CO.
Apr 1, 2007
#1
  • Apr 1, 2007
  • #1
Ok so I have been going through my car and fixing all the little bugs that come with building a whole new drivetrain. I thought my timing cover was leaking. So I brought home a coolant leakdown tester. I pulled the alt bracket off the car to see what the hell was going on. Well it appears that coolant is making its way through the threads and out between the head and the block. This is happening with two seperate bolts. They are located in the front bottom and rear bottom bolts on the passenger side head. I know that coolant is not going into the combustion chamber. The leak is slow no matter how hot the car is. This is because I believe that it is walking seeping through the threads. It is a brand new 347 short block. Brand new track heat heads and of course brand new gaskets along with ARP headbolts. Has anyone ever had this happen? The heads are torque down to arp spec. Second question is Could I just pull those two bolts(Doing so only one at a time. And throw some thread sealer on them and torque them back down?
 
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Mike92GT

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Jan 23, 2002
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Florida
Apr 1, 2007
#2
  • Apr 1, 2007
  • #2
Did you use any thread sealer on the bolts when you put them in? They thread into the water jacket, so they will leak pretty much every time if you don't put sealer on them. I think you should be able to go back and remove them one at a time and seal them, and then torque them back to spec.
 

jtfairlane

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Mar 5, 2006
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Apr 1, 2007
#3
  • Apr 1, 2007
  • #3
What Mike92GT said.

You need to use thread sealer, ARP makes a good one, on the threads of those short head bolts.
 

TomCat

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Apr 19, 2005
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Utah
Apr 2, 2007
#4
  • Apr 2, 2007
  • #4
Are you sure you can just pull them off? I'm not sure at all, but I know it only took one loose bolt on my intake mani to make it leak... and retorquing it wouldn't help much.
 
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Spook302

Member
Jun 21, 2005
109
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Durango CO.
Apr 2, 2007
#5
  • Apr 2, 2007
  • #5
Im not sure I can pull them out without a problem either. I was wondering If anyone had done this. I really dont want to pull everything apart again. That would suck. My worry is that if I pull one out that the head gasket would un seal.
 

jrichker

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Apr 2, 2007
#6
  • Apr 2, 2007
  • #6
Do one bolt at a time and you should be OK. Use ARP sealer or teflon pipe dope (my choice). Then check the torque all the head bolts. You will need to remove the valve covers and upper manifold to get access to the upper head bolts.
 

ozanracing

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Nov 28, 2006
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Apr 2, 2007
#7
  • Apr 2, 2007
  • #7
It's okay to pull the first bolt, clean it and seal it, then replace it and torque. Now do the other bolt. Okay your head gasket will be fine, and you don't have to remove anything..
 
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Spook302

Member
Jun 21, 2005
109
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Durango CO.
Apr 2, 2007
#8
  • Apr 2, 2007
  • #8
Ok so I am going to my work to grab some sealer for my head bolts. Ill tell you how it comes out.
 

ALMOSTFINISHED

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Jan 8, 2004
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Westchester County NY
Apr 2, 2007
#9
  • Apr 2, 2007
  • #9
I had to do the same thing on mine when I did the H/C/I swap. I used ARP head studs and sealer, I had read that the thread pitch of how the studs were cut allows a bit of seapage if you don't booger em up enough with sealer. I did one at a time and was fine, no leaks even with the s-trim blowin 15 psi down its throat. Take your time and it should be good to go.

Nick
 

BlownFiveLiter

have car, will race....wait, it doesn't run
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Apr 2, 2007
#10
  • Apr 2, 2007
  • #10
If you don't find any thread sealer, I used Permatex blue on my head studs, since that's what was specified by TFS. I know some people are reluctant to recommend using it because it's fairly thin and can run, but I've had no issues, so I'll go against the grain and recommend it.
 
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