Rear Head Bolt Seepage Continuous Problem - What To Do

Discussion in '94-95 5.0 - Specific' started by 94mustangsvt, Jul 29, 2014.

  1. 94mustangsvt

    94mustangsvt New Member

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    The driver side rear lower head bolt on my car keeps leaking coolant. I always put ARP thread sealant on all the bolts, but recently when I changed the cam I tried pulling the one bolt out and resealing it again.

    After a few days, the leak is now much worse. The car runs great and has no coolant in the oil. The current block has maybe 10K on it because I got a refreshed level 10 bare block from DSS. However, the seepage issue was a problem on my old block as well so a block issue is pretty much ruled out.

    Are the AFR heads maybe warped somehow? Last time I had them checked out they certainly didn't mention anything. Anyways, I'm trying to figure out what to do at this point. Should I try throwing a new head gasket on that side and hope it works or maybe try torquing the whole head down five more pounds? Any suggestions would be great, thanks.
     
  2. toyman

    toyman Active Member

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    Aren't these Torque-To-Yield head bolts? See here.
     
  3. 94mustangsvt

    94mustangsvt New Member

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    Stock are, but I have ARP head bolts. Supposed to be 80 ft. lbs on the long bolts and 70 ft. lbs on the short bolts with the AFR heads. I currently have them all at 75.
     
  4. BLWNBYU

    BLWNBYU Active Member

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    Which thread sealant did you use?
     
  5. RichV

    RichV Well-Known Member

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    I had a funky leak in a tranny one time that I was chasing for over a year. Turned out it was a hairline crack in the aluminum case. They had to put it under a blacklight to see it.

    I know this will be a PITA, but if you swap side on the heads and see if the leak follows the head or stays. At least you'll know to suspect the block or heads.
     
  6. 94mustangsvt

    94mustangsvt New Member

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    ARP thread sealant
     
  7. 94mustangsvt

    94mustangsvt New Member

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    I had the same issue on a previous block though so I'm suspecting the heads. I'm going to try taking it down 5 more ft. lbs. in hopes of a non-big pain in the ass fix.
     
  8. 330CubeGt

    330CubeGt Well-Known Member

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    I would probably do every bolt to 80-85 ft/lbs if I was in your situation. And see if it helps.

    -330CubeGt