Is it necessary to untorque a head?

P

Phil B.

Junior Member
A time ago I followed the discussion regarding the choice of gasket materials for the head to water neck interface. I had used the questionable thick paper gasket, and even though I'd dodged the bullet in previous assemblies, as I'm sure others have, I decided to yield to the popular "barners" opinion and substitute a sealer layer instead. Would it be wise to loosen the head in the opposite sequence of tightening to keep the forces equal and preserve the flat plane of the new Snyder's 5.5 head? Or maybe I'm just over thinking this. Thanks for thoughts, Phil
 
I usually try to loosen each head nut about a third of a turn until all have been lossened before I spin off the nuts, but when I haven't been so careful, I haven't warped my head enough so that any head gasket leaks developed in subsequent installations. I think you could get away with just loosening, removing and reinstalling the water neck nuts without warping the head enough to cause headgasket leaks. Better drain the radiator if you try it just in case. Of course others with more experience in this area might have better advice. Have the kids returned to UMF yet?
 
Methinks you are "overthinking" a tad. When I put on my gaskets, regardless of
type of head (high compression or regular head) and regardless of type of gasket,
I just torqued it down to 55 and used the pattern suggested in Les Andrews book.
It never caused a problem. after about fifty miles, re-torque it again just for fun
and giggles. I never had any problems with this procedure-----though I'm sure some
of the guys will disagree, lol. Hmmmmm, after re-reading your post, perhaps I mis-
understood your question.

Jack
 
I have taken loose individual stud nuts for whatever reason , then re-torqued them with no ill effects. This includes the pair that hold the water neck on. When I go back with them, I will re-torque the whole head in the proper sequence.

Having said that, unless there is a compelling reason to take the gasket out, and it's not leaking or hasn't broken the ears off the water neck, I'd just leave it until next time you have to remove it for some reason.
 
Thanks guys, probably when I was younger I would have just taken off the neck and not worried about the rest of the head (probably do that now). The engine has not had water added yet and has not been started since the rebuild. Think UMF opens this weekend, arrivals come on hurricane winds it seems, we'll be battening down tomorrow.
 
I would proceed With the gasket change as planned. Just undo the two water neck nuts. I encourage you to make the change, because mine took a long time to break. But it finally did, long after I thought I was an exception. Just found a puddle under the car one day.

Just reread your last post. All the more reason to change it now. They don't break until the paper gasket gets water saturated.
 
For my two peeny worth, when removing head I slacken each stud nut a 1/3 turn each till they're all slackened off
 
I'm sorry, but I have to restate my opinion, as I think the above is just not sound advice. Having lived through the paper gasket experience, it is asking for trouble, when now is a convenient time to guarantee a future failure will not happen. The paper gaskets squish out of the mating surface after the paper gasket gets saturated with coolant. When that happens, the stresses on the ears of the water outlet cause the failure. Right now your system is dry, the gaskets are firm, and you are being lured into a sense of success, when the stage has yet to be set for the failure. It's so simple now to just pull that gasket out, and either use the proper copper gasket, or no gasket at all, just a skim film of sealer. Just be sure both surfaces are flat, and you will be fine without worry. Leave the paper in there, and you SHOULD be worrying.
 
Thanks to all for your interest and advice, I'm inclined to make the change to sealer before I fill the system with water, Russ makes a good arguement for the "stitch in time saves nine " approach, and I will proceed by only removing the nuts holding the neck, and upon tightening retorque the whole head. Then again after fire-up, probably more than once. Phil
 
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