How to prevent frozen manifold nuts?

[Sparky]

The first time I removed my manifolds, two of the studs spun out of the block because the nuts were corroded tight. I put them back that way, but now I have a new set of studs and nuts and was wondering if there is a good way to prevent it. Will anti-sieze compound work, or will it just burn off?

 

[Pete]

Neverseeze or Ledplate work pretty good.

 

[Tin Lizard]

I've used copper anti-sieze (not the normal silver stuff) with some success. Had to look for it, but found it at NAPA.

 

[CarlG]

I've used copper anti-sieze (not the normal silver stuff) with some success. Had to look for it, but found it at NAPA.

This is what I use.

 

[Jim Mason]

use female manifolds...fwiw,jm

 

[Cool Hand Lurker]

Tip that I learned from a factory guy who had to attach wires to a high temp industral heating unit was to dip the screws in Phillips Milk of Magnesia first. Then the screws always came out again when they had to change the element.
It has worked well for me on exhaust manifold bolts. And not expensive.

 

[Tim B.]

Just a word of caution. If you use anti sieze you will have to adjust the torque because of the lubricant. A general Industrial standard is to reduce the torque value by about 20% for Anti sieze because it eliminates the running torque normally included in the torque value when studs are torqued dry. Tim

www.imperialsupplies.com/pdf/A_FastenerTorqueCharts.pdf

 

[CarlG]

From other threads here, the consensus was just to snug them up, not torque to any particular value.

 

[5window]

use female manifolds...fwiw,jm

And, wear long underwear.

 

[Sparky]

I've used copper anti-sieze (not the normal silver stuff) with some success. Had to look for it, but found it at NAPA.

Thanks, I'll head to my local NAPA.

 

[Doug in NJ]

They make the copper stuff in stick form, sort of like a oversize tube of chap-stick. It's much less messy than the kind in the jar with a brush in the lid.

Doug

 

[Old182]

Sparky, not to make it any more complicated than it needs to be, but be aware that studs should have 2 different class of fits; the fine threads (where the nut goes) is a Class 2 fit or what we normally deal with when using nuts and bolts. But the coarse threads (the end that goes into the base) should be a Class 5 fit or an interference fit. It's the Class 5 fit that holds the stud in the base and allows the nut to be removed with the stud remaining firm. Of course, after 80+ years of use, often the nuts tend to rust or otherwise bind to the fine threads and the stud comes out instead. The studs that I have purchased from the Model A supply houses have not had the Class 5 fit on the coarse end and freely screw into the base. Studs should have to be "driven" usually using double nuts on the fine end. It's advisable then to use some sort of thread locking material on the coarse end of the studs if they can be easily screwed into the bolck. $0.02.

 

[Sparky]

Thanks for the tip, I do have some loctite.

 

[montanafordman]

It's advisable then to use some sort of thread locking material on the coarse end of the studs if they can be easily screwed into the bolck. $0.02.

So would you recommend a small amount of blue loctite on the course threads? And maybe anti-seez on the fine threads?

 

[Old182]

Montana, yes. With non-interference fit coarse threads, and assuming you would chase the block threads with a standard tap, it's probably the best you could do given the situation. There might be others on this site with machining experience that could advise otherwise. I think the only viable alternative would be to clean the original studs (if they're not too corroded) but not run a die over the coarse threads - just a wire wheel.

 

[Tin Lizard]

Lots of cool tips here about the torque values, stick form of copper anti-seize, and now the proper fit of studs. Hadn't thought of any of it, but glad to have been informed. Let me try to add one more: use a rethreading tap or thread chaser on existing threads to help prevent cutting too much material. I have a Snap On set of the rethreading variety that's great, and not as expensive as most Snap On tools.

Rethreading:
http://buy1.snapon.com/catalog/tools.asp?tool=all&Group_ID=1146&store=snapon-store

Thread Chasing (pricey):
http://buy1.snapon.com/catalog/tools.asp?tool=all&Group_ID=1150&store=snapon-store

I agree the wire brush on external/male threads is best if sufficient.

Edit: just found this is covered quite well here:
http://www.fordbarn.com/forum/showthread.php?t=60697

 

[bobpo]

This is what I use.

I've used the copper colored stuff for years and it has never failed me. Got it from my Brother-in-Law who is a Machinist by trade and swears by it. Good enough for me.....