Should I Helicoil for exhaust manifold studs?

[NHerron]

Hey guys I just got this ARP stud kit for the exhaust side, and would really like to prevent them from snapping/seizing for ease of removal in the future. Some nice high quality stuff I must say! Anyway, since the ARP stuff is SS and it's threading into aluminum, should I Helicoil all the holes so the engaging metals are the same? I already have to do it to at least one because the aluminum threads were pulled out.

Just a thought, let me know if it'd be worth the hours worth of work. Had to weld a nut to the OEM stud to get it out today, and I rather not have to do it again

 

[JacksonAuto]

Depends on what kind of shape the female threads are in. If you remove the original studs and the threads in the head are in good shape then just use some anti-seize on the new studs. More often than not the threads will be rolled/damaged and will need an insert. This is a result of not only the age of these engines now but also from the weight of a heavy manifold and turbo hanging off of the studs.

 

[livedsm4g63]

How will anti-seize help the studs/threads after a few heat cycles?

 

[JacksonAuto]

Anti seize isn't going to burn off or wear away unless you use a cheap product. Nickel based anti seize will maintain its properties in working environments in excess of 2600*f. It prevents corrosion and galling. I've disassembled engines that I assembled over 10 years ago and the anti-seize was still present on the exhaust fasteners.

Avoid products with copper or any product which is thin and greasy. A good anti-seize will contain over 40% pure nickel and be a thick, nasty paste which seems to jump out of the container and right onto your clothes or anything else you're trying to keep clean.

 

[NHerron]

That part of the manifold doesn't get nearly as hot as the collector area. How do I know? I use a paint stick to mark any bolts I torque down and the marks for the exhaust studs were still bright and red the same as they were when I first marked them. The manifold to turbo bolt marks were gone the first couple days

Well would I be at least significantly better if I helicoiled the studs + antiseize vs just antiseize? This is my hobby so a little extra time can be spent, it's okay. But I just want to be sure before I do it that if I Helicoil them all and one day a stud decides to seize up, then I'd have to double helicoil or something. So I don't want to run into that problem.

I've heard of people automatically helicoiling aluminum threads even though they aren't damaged in the first place, so that's how I come to think about this

This is the kind of AS I have. I also have the silver stuff from NAPA
http://www.jbfleet.com/MSDS/38830.pdf

 

[NHerron]

Just wanted to update, I ended up Helicoiling the studs, some I really didn't need to but enough of them needed it so I just went ahead and did them all. Took me about an hour. Used copper AS on the studs threads as well as the nut ends. Did that to all of them except the middle lower one, which I put RTV on since it threads into an oil galley.

 

[silvreclips]

Used copper AS on the studs threads as well as the nut ends.

Did you not read all the post in this thread? Do not use copper based anti seize on exhaust components. The particles melt under extreme temperatures and you will never get the studs back out. I would remove that stuff before starting that motor.

 

[NHerron]

I'm not too worried about that part of the exhaust since it doesn't get nearly as hot. Did you read the PDF on the stuff I'm using? http://www.jbfleet.com/MSDS/38830.pdf

It's good for the temperature anyway.