how to install stainless studs/bolts

I'm preparing to reinstall the cylinder and head on a '74 850 (fairly low mileage) using stainless hardware and want to ask what best practice is regarding Loctite (blue) vs. copper antiseize compound?

Right now, I'm strongly inclined to use antiseize since I'm putting SS studs into an aluminum alloy but given the need to torque everything down, I'm having second thoughts about that approach (antiseize) due to the impact on torque settings - and I don't want to over torque into alloy casing and cylinder head...

Also, what's the concensus on securing the 4 3/8"x16" long bolts for cylinder to crankcase? In this case, I have new stock (steel) bolts. I'm thinking blue Loctite here, and slowly torqueing them down.

Cheers,
Kevin

Hi Kevin,
Sorry I have no answers for you but I am extremely interested in the answers you receive since I am considering doing the same for my 750.

Ed

The ARP SS bolt kits that CNW sell comes with instructions to install with thread lubricant.

Re: Compatibility of fasteners with base metal:

Here is a simple chart:

https://www.fastenal.com/content/feds/p ... rosion.pdf

The following link shows a cold galvanizing product that should provide cathodic protection when applied to stainless fasteners used in aluminum base metal. It is not up to NASA standards, I'm sure, but it can be obtained rather easily. This product applies a zinc coat, and from the chart above, one can see that zinc in aluminum is compatible.

http://www.rustoleum.com/en/rustoleum/p ... pray-paint

Loctite affords cathodic protection (per communication with Loctite technical support). However, when applied, Loctite is liquid and will decrease friction somewhat, likely not as much as oil, but torque values may differ.

Slick

I use low strength Loctite (the purple one) on my stainless studs.
Targeted heat and a stud extractor gets them out with zero damage to your ally.

I use Copaslip between the studs and the nuts.


Not sure I'd be brave enough to use blue loctite, as you may damage the thread in the ally when you want to get your fasteners out.

I think it might be difficult to retorque the head after heat cycling or whatever if using a thread locker. You may want to read Jim Comnoz's posts about head torque loosening and the CNW "waisted bolts" and Jim Schmidt's triangular cross section bolts before using thread lockers. Mine are simply stock stuff so I don't really have personal experience.
Lance

Recommending thread locker on the studs is different from doing that on the bolts.

I use ARP ultra-torque lube on all threads, stud or bolt, steel into aluminum, stainless into steel. It prevents galling as well as delivers accurate torque readings. Never had a reason to use anything else.



http://arp-bolts.com/p/arpultratorque.php

Thanks all. This is part of the dilemna - using antiseize on a stud with threadlocker on a nut most likely means the stud comes out on removing any nut that's threadlocked. Also, as Lance said, a stud with antiseize with an attached threadlocked nut seems like it won't retorque properly - the threadlock will have 'dried' and locked the nut to stud - and stud needs to be bottomed out in the casing so tightening a locked nut onto a 'glued' stud... an obvious bad option.

So that's where I get the idea to threadlock stud and antiseize the nut. IIRC, torque settings are approximatley 20% lower for lubricated vs. 'bare' metal but more homework needed here too.

Of course, the antiseize formula is important for compatability as Slick notes, especially in aluminum alloy...

Blue Loctite looks to be too much, if at all.

Man, this really makes me appreciate the knowledge a good machinist brings to the table. What I thought was a simple task (replace nuts/bolts/studs) turns out to be significantly more complex than I'd have guessed. Despite a degree in automotive engineering, we never covered this level of detail.

I'll read through some of the helpful links from the replies and many thanks once Slick sends (thanks in advance).

Ron, ultra torque looks to work up to 360 degrees which I recall someone recently saying was a pretty common heat range for head/cylinder and a Combat could see 400 degrees.

Of course, most engineers build in a safety figure so that 360 is probably conservative and I guess you've not had any problems.

arbrnrngr said:

Ron, ultra torque looks to work up to 360 degrees which I recall someone recently saying was a pretty common heat range for head/cylinder and a Combat could see 400 degrees.

Of course, most engineers build in a safety figure so that 360 is probably conservative and I guess you've not had any problems.

Click to expand...

Nickel - good to 1315C - http://www.crc.co.nz/Nickel-AntiSeize-- ... a8a27fe61/

I hope you all can open the new links that I have put up.

Re: arbrnrngr's comment about blue Loctite. I usually "blue" most everything, and have never had difficulty removing any nut or stud (except it cannot be done with the fingers). keeping the finger loosening in mind, I do not blue whatever poses a difficulty (like the magneto nuts on Atlas/Dommies). I use red Loctite sparingly ... only in the most critical of applications, and where I can apply heat should I ever want to separate the parts.

Slick

I just installed cNw SS kit, barrel, head studs and waisted head bolts. Blue loctite on studs and oiled bolts and nuts. No loctite on anything that needs
re-torquing.

FWIW, if there is a concern about using Loctite and having it affect torque values they make a green wicking type that is used after the parts are assembled. As far as using stainless I was always told to use anti seize anytime dis-similar metals come in contact with each other. Stainless head bolts sound like a whole different animal and I would follow the company's instruction and only use a product that was specifically for that purpose.
Pete

texasSlick said:

Loctite affords Catholic protection ...

Click to expand...

I'm not even sure what that means, but please, let's keep religion out of the conversation!

Nater_Potater said:

texasSlick said:

Loctite affords Catholic protection ...

Click to expand...

I'm not even sure what that means, but please, let's keep religion out of the conversation!

Click to expand...

Cathodic! .... Cathodic, the word was cathodic! D@&m spell check!

Catholic protection is .... celibacy.

Slick

ha ha ha....that definition never was used by the Irish!
However in this case I think you will see the religious meaning is last....


catholic
[kath-uh-lik, kath-lik]

adjective
1.
broad or wide-ranging in tastes, interests, or the like; having sympathies with all; broad-minded; liberal.
2.
universal in extent; involving all; of interest to all.
3. pertaining to that religion

................priest a rabbi and a minister walk into a bar........................

Onder said:

ha ha ha....that definition never was used by the Irish!
However in this case I think you will see the religious meaning is last....


catholic
[kath-uh-lik, kath-lik]

adjective
1.
broad or wide-ranging in tastes, interests, or the like; having sympathies with all; broad-minded; liberal.
2.
universal in extent; involving all; of interest to all.
3. pertaining to that religion

Click to expand...

The way I see it .....

If you want to instal / insert your stud / bolt into a receptacle ....
but you cannot use a covering ...
and you cannot employ chemical intervention ...
and you cannot withdraw said stud / bolt if fluids will escape ...
then the only safe sure protection is celibacy .... that is, keep your stud / bolt away from any female receptacles.

Isn't that the Catholic protection method?

Slick

Isn't that the Catholic approach to being Cathodic?