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Discussion Topic:
Head Nut Torque Setting
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BigBlockFord |
04-20-2010 @ 6:30 PM
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Member
Posts: 68
Joined: Nov 2009
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My V8 appears to have coolant corrosion coming from some of the studs. What is the correct torque setting for the heads? Common issue???
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ford38v8 |
04-20-2010 @ 7:36 PM
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Senior
Posts: 2769
Joined: Oct 2009
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Big, assuming you're asking about a Flathead, no amount of torqueing will seal the leaking coolant. The problem is that the studs were installed without the benefit of sealant, needed for those studs that penetrate into the water passages.
Alan
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BigBlockFord |
04-21-2010 @ 7:53 PM
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Posts: 68
Joined: Nov 2009
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Would "Silver Seal" be a product that may help prevent the leakage?
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ford38v8 |
04-21-2010 @ 9:33 PM
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Senior
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Big, I would think that it wouldn't hurt to try, but haven't heard of anything being successful other than actually pulling the stud and using a proper thread sealer on replacing it. If you do pull it, though, remember that the threads within the water passage will be rusted, and will need to work back and forth incrementally for successful removal without damage to the block threads, or breaking the stud. this can be a tricky job unless the heads are removed, providing more grip on the stud.
Alan
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37RAGTOPMAN |
04-23-2010 @ 6:16 AM
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Senior
Posts: 1965
Joined: Oct 2009
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BIG BLOCK What you could try is to drain the coolant, just back off the nuts that are leaking,wind string or even better would be plumbers teflon tape, the old timers used string under the nuts, this is worth a try and will only take minutes, just retorque the head nut back to specs,run the engine to operating temp and retorque when cold. you will not have to replace 2 headgaskets, and silverseal or bar leak will also help, just use a little bit, hope this helps my 3 cents worth 37RAGTOPMAN Pulling the studs and sealing them will be better, but that also is not a guarrantee.it can still leak past the head gasket and seep up the stud and out from the under the nut,,
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supereal |
04-23-2010 @ 9:10 AM
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Posts: 6819
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"Back in the day" it wasn't uncommon to have a "wet" stud after backyard rebuild because we seldom replaced the studs, as we do today. You can try a good sealer, such as Barr's, but it is likely that it won't hold because the stud is probably eroded enough to allow considerable coolant to escape. Many of the stud threads in these old blocks are fragile, and we often have to Helicoil several holes to allow sufficient torquing without pulling out a stud.
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BigBlockFord |
03-13-2011 @ 2:42 PM
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Member
Posts: 68
Joined: Nov 2009
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What is the appropriate setting for torquing the head? Also other common torque settings? Is there a cheat sheet somewhere on basic torque settings?
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37RAGTOPMAN |
03-13-2011 @ 5:11 PM
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Senior
Posts: 1965
Joined: Oct 2009
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I torque mine to 50-55 lbs, just make sure you studs and nuts are not frozen, the nuts must move on the stud, back them off before torquing down, and do it cold, than run the car and retorque after putting a few miles on HOW did you make out with the seepage around the studs, a friend of mine works for a GM dealer, he says, every new car gets 2 tablets of a coolant sealer,its like a solid bars leak, using just water till the leakage stops, it seals up better then antifreeze matter if fact you can buy them from any GM DEALER. hope this helps 37RAGTOPMAN
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Stroker |
03-13-2011 @ 5:16 PM
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Senior
Posts: 1460
Joined: Oct 2009
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Best source I've found for all-around torque spec's: http://www.vanpeltsales.com/FH_web/flathead_specs-85to100mid.htm
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supereal |
03-14-2011 @ 8:59 AM
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Senior
Posts: 6819
Joined: Oct 2009
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For cast iron heads, 50-60 foot lbs. For aluminum heads,35-40 ft lbs. Be sure that the head studs and their threads are clean and dry, and the nuts also have clean threads, or the torque readings will not be correct. We use washers under the nuts on aluminum heads to protect the surface. No washers on iron heads. Be sure to tighten in sequence, beginning at the center. Recheck after all nuts are in place, then again after 100 miles or so. We recheck them when the engine is cool.
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