Head studs

[Mikeinnj]

How tight do i want to put these into the block ?
Should i use sealant of any kind or an anti seize ?
Thanks Fordbarn !

[PC/SR]

Torque questions come up here occasionally for different parts. Here is a link to a torque chart, which is a good starting place for values. There are others on-line.
http://www.raskcycle.com/techtip/webdoc14.html

[Larry Seemann]

You don't torque the studs into the block. I just put them in with a pair of regular pliers until snug. I use anti seize on the block threads.

[Dave in MN]

I agree with Larry... do not run them tight into the block.
James Rogers gave me this tip and I find it to work rather well. This tip is a bit counter to convention but hear me out. James explained to me a "trick" some engine builders do when assembling an engine is to use Blue or medium strength threadlock on the studs when installing them. As you install the studs, apply liquid or gel threadlock to the de-greased course threads and set the studs at the desired height. Test fit a couple studs so you get the correct amount of the stud's dome above the nut with the head and head gasket thickness factored. Let the threadlock set up over night and continue with assembly. The threadlock will keep the studs from turning further into the block as you torque the head. The threadlock will keep the studs from rust seizing in the head much like a good antiseize will. A bit of heat on the studs will soften the threadlock when you want to remove the studs. I have used this method on the last 8 engines I have assembled and I like the results. Thanks James!
Good Day!
Dave in MN
www.durableperformance.net

[Dave in MN]

Originally Posted by fordgarage

I do similar, except I always used Permatex #2, not threadlock.

Hi Vince, good to hear from you!
I understand the benefit to sealing with Permatex if the threaded stud area is compromised and open to the water jacket . I have used it occasionally for this purpose. I have not tried your method on all studs so I have two questions: When using Permatex #2, will it set up enough to hold the stud from rotating when torquing the head. If so, how long do you leave it "dry" before installing the head?

The reason I use threadlock and often the available "accelerator" is to maintain the height of the stud for good presentation. Every once in awhile, prior to using threadlock, I would get one that wants to spin in further when tightening the head nut and I end up fighting it to maintain proper height above top of block.
Thanks!
Dave in MN

[CarlG]

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Originally Posted by fordgarage

I do similar, except I always used Permatex #2, not threadlock.

Same here. I typically let it set overnight.

[Rich in Tucson]

What I have seen done several times is a little different than that mentioned above but similar. It is to use a hard setting Loctite (I think blue works; heat must be used to loosen it) on the head nuts on the fine threads of the head studs on the bench to set the stud dome above the head nut. Let cure. Then Permatex #2 is used on the coarse threads which are screwed in with the head sitting on the block. This may take some finagling to get the studs through the head and gasket while ensuring that no cross threading into the block occurs. Then the head is torqued as usual. I have heard it argued that this makes it more difficult to get the right torque value since you are adjusting with coarse threads rather than fine threads but if everything is in good shape (meaning primarily the threads in the block) I disagree. If you pull block threads, it needed a Helicoil or other fix anyway.

[Geo. H]

Seems to me like using the coarse threads for the torque value won't work. The thread pitch is different, so a different torque value would apply. Besides that, the main reason for using studs is to eliminate wear on threads which can't be easily replaced.

[Brentwood Bob]

Rich, this would have helped me replacing loose studs without removing the head. Instead I wirebrushed the replacement, and put antisieze on the coarse threads, then the replaced stud worked loose in a relatively short time.

[Brentwood Bob]

Mikeinnj, there is a thread on 6-5-2011 titled loose head nuts. It might help. Bob

[MikeK]

Henry's original dome-headed studs bottomed out when originally installed in a new block, so their sinking further in was not an issue.

If you need a stud to be higher, shim it at the bottom of the hole with punched metal discs, similar to brake pills. When you find the correct shim/height combo with the studs themselves (not the top nuts) torqued in about 20 ft/lbs (via double nut or vice-grips on the shank) you can remove them and re-install to 20 ft/lbs with permatex#2 or other favorite waterproof goo to prevent 'wet' holes.

Now, because the studs have perfect height and are somewhat tight, they will not wander up or down during torquing/re-torquings of the head nuts.

[AL in NY]

I use a method similar to MikeK's, but I use small flat stainless steel washer and silicon gasket sealer on the threads to keep the water out of the stud hole. My thinking here is if I ever run pure water in the cooling system, some may seep into the stud holes. If it remains there as pure water, it can freeze and fracture out the bottom of the stud hole and cause leak. Just another thought on the subject...............

[Dave in MN]

Originally Posted by MikeK

Henry's original dome-headed studs bottomed out when originally installed in a new block, so their sinking further in was not an issue.

If you need a stud to be higher, shim it at the bottom of the hole with punched metal discs, similar to brake pills. When you find the correct shim/height combo with the studs themselves (not the top nuts) torqued in about 20 ft/lbs (via double nut or vice-grips on the shank) you can remove them and re-install to 20 ft/lbs with permatex#2 or other favorite waterproof goo to prevent 'wet' holes.

Now, because the studs have perfect height and are somewhat tight, they will not wander up or down during torquing/re-torquings of the head nuts.

Mike,
Thanks for the info on Henry's method....
Regarding shimming with "pills" and torquing to 20#. I see a lot of blocks that have been chased with a standard tap and the fit of the stud to the block is a bit loose. Add 20# of pressure on the stud to the 55# torque from the head nut and I think one would see an increase in failure of the threads in the block. I am just speculating! I guess if the threads are already loose...they are already in a state of failure.
Good Day!
Dave in MN

[Mikeinnj]

Thanks everyone for all the tips and suggestions !