How to remove broken exhaust stud

[coreydmc]

Stayed up last night. Job is all done. Thanks DMC-81 for the advice and picture!

[DMC-81]

Stayed up last night. Job is all done. Thanks DMC-81 for the advice and picture!

Excellent. You are welcome, glad that it was helpful.

[David T]

Typically you should not use a sealant (even high temperature) on the exhaust manifold gaskets. That said, sometimes it is necessary especially if there is a need to hold the gaskets in place because there are no studs. As for using too much Never Seize, if the studs loosen up or break it is because the holes in the exhaust manifold are not large enough and when the parts expand they put huge sideways stresses on the studs. After a few cycles bad things start happening. Cast iron expands a LOT under all of that heat and if you don't allow for it things happen. If the head surface is flat and the manifolds are flat the gaskets should seal properly without the need for any sealant. In fact, back in the 80's many cars didn't use gaskets. The theory was, let them leak, air would get in, the oxygen would help to burn any excess HC and the tailpipe emissions would be lowered. Didn't work so well. It raised engine bay temps, was noisy and reduced HC insignificantly. It caused may automakers to go to an air injection system, adding an air pump and pumping air into the exhaust manifolds. That was eventually discarded because the systems didn't last long.

[DMC-81]

Typically you should not use a sealant (even high temperature) on the exhaust manifold gaskets. That said, sometimes it is necessary especially if there is a need to hold the gaskets in place because there are no studs. As for using too much Never Seize, if the studs loosen up or break it is because the holes in the exhaust manifold are not large enough and when the parts expand they put huge sideways stresses on the studs. After a few cycles bad things start happening. Cast iron expands a LOT under all of that heat and if you don't allow for it things happen. If the head surface is flat and the manifolds are flat the gaskets should seal properly without the need for any sealant. In fact, back in the 80's many cars didn't use gaskets. The theory was, let them leak, air would get in, the oxygen would help to burn any excess HC and the tailpipe emissions would be lowered. Didn't work so well. It raised engine bay temps, was noisy and reduced HC insignificantly. It caused may automakers to go to an air injection system, adding an air pump and pumping air into the exhaust manifolds. That was eventually discarded because the systems didn't last long.

David, that was not my experience. As I said, the studs loosened up because of vibration/flexing of the engine. The holes were not an issue. Too much of a good thing can have detrimental effects...just like too much di-electric grease. I had an annoying problem with the dash warning lights coming on after a battery install in the same daily driver car. After months of frustrating troubleshooting, I traced it to an excessive amount of di-electric grease applied by the auto parts store when they installed the new battery. I wiped off the excess, reinstalled the terminals, and BOOM, problem solved.

[Ron]

I picked up some high temp manifold gasket RTV sealer to use on both sides of the exhaust manifold gasket.

You do not want to use RTV sealer.

If you have imperfections in the head, it might make sense to use RTV High-Temp gasket MAKER, depending on how bad it is.
If you have imperfections in the manifold, you should have them resurfaced.
You are better off without RTV if the surfaces are ok because it is only good to 650F.

Note some re-sellers say you can use it on exhaust, but the official site only lists "Valve covers, oil pans, timing covers, and thermostat housings" on their Application tab.

EDIT: If you must/do...Don't use the Permatex RED, use something like Permatex® Sensor-Safe High-Temp RTV Silicone Gasket Maker.

[Ron]

David, that was not my experience. As I said, the studs loosened up because of vibration/flexing of the engine. The holes were not an issue. Too much of a good thing can have detrimental effects...just like too much di-electric grease. I had an annoying problem with the dash warning lights coming on after a battery install in the same daily driver car. After months of frustrating troubleshooting, I traced it to an excessive amount of di-electric grease applied by the auto parts store when they installed the new battery. I wiped off the excess, reinstalled the terminals, and BOOM, problem solved.

+1

I've always make sure the threads are clean then put a dab on my finger and rolled the threads in it. Plenty!
This weekend, I removed exhaust bolts and nuts that I put in 389 Hypo manifolds 18 years ago (and it basically sat for the last two years) -- No problems.

[David T]

Once heated the Never Seize becomes a powder and is not going to make things shake apart. If the parts loosened up it is because the holes in the manifold were not large enough to allow some expansion or you did not torque properly. No one else has experienced this problem so it is something unique to the way you did it, not the use of Never Seize.

[DMC-81]

Once heated the Never Seize becomes a powder and is not going to make things shake apart. If the parts loosened up it is because the holes in the manifold were not large enough to allow some expansion or you did not torque properly. No one else has experienced this problem so it is something unique to the way you did it, not the use of Never Seize.

David, that is an incorrect assumption, and it's pretty humorous for you to suggest that I didn't torque the studs properly. I always research and fastidiously use proper torque specs, as my posts here will indicate.
Like I said previously, an excess amount of the compound WAS the cause. Removing the excess on the same studs installed into the same manifold with the same hole diameter resolved the problem.

By the way, here are the directions on a Never Seize product:

DIRECTIONS:

1. For best results, part surfaces must be clean and free of grease.
2. Apply a light coating of product to parts.
3. Assemble parts.
4. Wipe away any excess compound.

https://www.permatex.com/products/lu...e-lubricant-2/

[David T]

I never said to get sloppy with the stuff but I never had the hardware loosen up because of Never Seize either. What I have learned over the years, if the holes in the manifolds make it tight to install over the studs, the expansion and contraction over time will loosen things up and/or fracture the studs. I always check for enough "slop" to allow for expansion. If necessary I enlarge the holes. The surface where the nut rides on the manifold must be flat and square and I use flat washers. If you install the long threaded end of the studs into the cylinder head it is possible you "bottomed out" on the threads on the "short" side and hit your torque before you actually got the joint under full compression. I also like the S/S hardware kit that PJ Grady sells, very nice but pricey. When working on marine engines they use brass nuts and I never had a problem removing them even if Never Seize was not used. Removing steel or S/S hardware from an aluminum head is always problematic especially if Never Seize is not used.

[DMC-81]

I never said to get sloppy with the stuff but I never had the hardware loosen up because of Never Seize either. What I have learned over the years, if the holes in the manifolds make it tight to install over the studs, the expansion and contraction over time will loosen things up and/or fracture the studs. I always check for enough "slop" to allow for expansion. If necessary I enlarge the holes. The surface where the nut rides on the manifold must be flat and square and I use flat washers. If you install the long threaded end of the studs into the cylinder head it is possible you "bottomed out" on the threads on the "short" side and hit your torque before you actually got the joint under full compression. I also like the S/S hardware kit that PJ Grady sells, very nice but pricey. When working on marine engines they use brass nuts and I never had a problem removing them even if Never Seize was not used. Removing steel or S/S hardware from an aluminum head is always problematic especially if Never Seize is not used.

No David, you didn't say sloppy, but you said:

MAP gas doesn't get it hot enough. An Oxy-Acetalyne torch will do it. Heat it up to cherry red, let it cool, heat it again and then remove it, along the threads, from the head. Then Heli-coil it. Use plenty of Never Seize when you put it back together.

And then:

Never Seize. Use liberally on all of the exhaust hardware but be careful, it can get messy.

... which is more than the product's instructions of a light coating.