Manifold exhaust studs
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Exhaust Manifold studs
Well I used my handy dandy stud removal tool. Heated the manifold around the stud as hot as it would get, all three snapped right off.
I have all the tools to drill and tap this, however I would like some tips from people who have done this before.
I guess my major concern is drilling the stud out straight down the center without getting into the original threads. Is this a valid concern, or does it not even matter since I will be cutting new. Thanks
[Modified by Robd, 9:09 AM 8/25/2003]
I have all the tools to drill and tap this, however I would like some tips from people who have done this before.
I guess my major concern is drilling the stud out straight down the center without getting into the original threads. Is this a valid concern, or does it not even matter since I will be cutting new. Thanks
[Modified by Robd, 9:09 AM 8/25/2003]
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Re: Exhaust Manifold studs (Robd)
[QUOTE]Well I used my handy dandy stud removal tool. Heated the manifold around the stud as hot as it would get, all three snapped right off.
I have all the tools to drill and tap this, however I would like some tips from people who have done this before.
I guess my major concern is drilling the stud out straight down the center without getting into the original threads. Is this a valid concern, or does it not even matter since I will be cutting new. Thanks
[QUOTE]
Your concern is a valid one.
Use a dremel tool to grind the surface of the broken stud as flat as possible, then use a center punch to carefully mark the center of the stud.
New carbide drill bits would be a good idea but not completely necessary, high speed steel will work too. Start with a small drill bit (probably about 1/8"), go very slow, remove the bit often to clean out the metal chips, use lots of oil on the bit, and make sure the manifold is securely held in a vice.
Once the small hole has been drilled move up the next bigger size drill bit, use the same proceedure, keep increasing the drill bit size by one or two sizes until the hole is the correct size for your ez-out or tap.
I would suggest trying an ez-out first (gently to avoid breaking the tool off in the hole). Once the hole is the correct size for the ez-out heat the manifold around the stud to cherry red, then soak it with penetrating oil while it is still hot, then reapeat this 10-15 times before you ever go near the hole with the ez-out. This alternating expanding and contracting of the metal will help break the rust bond between the stud and the manifold, and spraying the penetrating oil on it while it is hot (expanded) will increase the chances of the oil getting deeper into the threads.
Now carefully use the ez-out to back the stud out of the threads, if it still refuses to move don't be afraid to use more heat and oil.
This proceedure worked very well when I did mine manifold studs, and it surprised the heck outa me because I had never before had any sucess with ez-outs.
In the event it does not work, you can simply continue drilling the hole larger until it is the correct size to use a tap.
I have all the tools to drill and tap this, however I would like some tips from people who have done this before.
I guess my major concern is drilling the stud out straight down the center without getting into the original threads. Is this a valid concern, or does it not even matter since I will be cutting new. Thanks
[QUOTE]
Your concern is a valid one.
Use a dremel tool to grind the surface of the broken stud as flat as possible, then use a center punch to carefully mark the center of the stud.
New carbide drill bits would be a good idea but not completely necessary, high speed steel will work too. Start with a small drill bit (probably about 1/8"), go very slow, remove the bit often to clean out the metal chips, use lots of oil on the bit, and make sure the manifold is securely held in a vice.
Once the small hole has been drilled move up the next bigger size drill bit, use the same proceedure, keep increasing the drill bit size by one or two sizes until the hole is the correct size for your ez-out or tap.
I would suggest trying an ez-out first (gently to avoid breaking the tool off in the hole). Once the hole is the correct size for the ez-out heat the manifold around the stud to cherry red, then soak it with penetrating oil while it is still hot, then reapeat this 10-15 times before you ever go near the hole with the ez-out. This alternating expanding and contracting of the metal will help break the rust bond between the stud and the manifold, and spraying the penetrating oil on it while it is hot (expanded) will increase the chances of the oil getting deeper into the threads.
Now carefully use the ez-out to back the stud out of the threads, if it still refuses to move don't be afraid to use more heat and oil.
This proceedure worked very well when I did mine manifold studs, and it surprised the heck outa me because I had never before had any sucess with ez-outs.
In the event it does not work, you can simply continue drilling the hole larger until it is the correct size to use a tap.
