The Stovebolt Site Forums The Shop Area Engine Shop Studs?

I'm looking to pull my intake and exhaust manifold off. The studs between the ex. manifold and exhaust pipe are shot. Are these studs pressed in? screwed in? How much trouble/$ am i looking at to get them replaced?

Thanks guys!

Bryan,

Presumably you are referring to a 216/235/261?
The studs on those engines are screwed in.

Maybe someone who is good with a torch will post an response describing how to heat the stud/manifold before trying to remove the stud.

- If you are very lucky, you will be able to unscrew the studs.

- More commonly, the stud will break and you will have to remove the broken piece.

- If you are very unlucky, you will break the manifold around the stud when you try to remove the stud. You'll still have to remove the broken piece and you will have to repair the break (if possible, depending on the break).

All three of the above have happened to me. The middle possibility is the most common.

Tim

Mine are screwed in , if Your talking about the two studs at the bottom of the exhaust manifold mine are 7/16 course thread into the manifold and 7/16 fine to the pipe I took mine out and ran a tap into the manifold and they were OK but if Yours are bad You can install Healy coils in 7/16 course they are easy to install and are very strong I also replaced the studs You can get new ones at any FLAPS.


Pete

If your exhaust studs are 7/16 they must have been replaced. They should be 3/8.

Bryan. Bring them over to my shop unless you have a torch. Don't try to un screw them, they will break off. George

wow! fast response time guys!

good news too, I was afraid that they would be pressed-in and i would have to take them to someone who has a bearing press.

Sounds like I need to soak them for about a week with Wd-40 or something...

I apprecite the help!

Use Kroil instead of WD-40, and heat the stud and the manifold area red hot before you even try to remove them. Once the stud moves, work it back and forth a little at a time. If it gets even slightly sticky, use more heat!
Jerry

Use Kroil, or at least PB Blaster. WD-40 wont cut it.

Use plenty of heat.

I sometimes weld a nut on the end of studs to get a socket on it. As Tim mentioned, most likely something will go wrong. With that stated, take George up on his offer.

Scott

I plug weld a nut to them. After that cools, I heat the manifold and they usually screw right out. Usually just the welding knocks them loose, but a little heat will cause the cast to expand. Heating the cast to red hot won't hurt it.

Use a rosebud tip on an oxy/acc. torch, heat the stud where possible..cherry red and it should turn...with a little luck.

Just checked My 235 and they are 3/8 so My 216 that is in the truck must have been a fix it would have been a easy fix just drill out the bad 3/8 tread and rethread to 7/16 .

Pete

..... IF you have to drill them out and don't have the proper tool I highly suggest taking them to a machine shop. I have a set of 283 headers that were give to me and ALL the studs broken off. Without a torch I tried the kroil and other things but nothing doing. Then I tried to drill one one out and even though I got it about as centered as it can get I stopped.... took them to a local machine shop and had the guy with the proper tools do it. He drilled them out, rethreaded all 6 of them and charged me $20. The best money I ever spent.
My advice....is to take George up on his offer. You won't regret it!! I also would put a tat of anti-size on the stud when you put them in and use BRASS nuts.

I just wanted to update everyone on a neat little trick I learned.

When I tried to pull the manifold, I snapped both bolts off flush with the surface. (Why am I not surprised?) After cursing a little, and moving throught the 12 step program, I finlly accepted my current situation and broke out the drill.

Drilling bolts always makes me nervous, because try as I might, I am never able to drill down through the dead center (even if I use a center punch). Which is what happened to me on this occasion. So, after the initial drilling I started gradually drilling bigger and bigger (1/64" at a time) until I barely could make out the threads on one side of the hole.

This is where the trick comes in.

Break out your dremel tool (real cheap knock-off's at harbor freight) and chuck up a tungsten carbide cutting bit.

http://www.toolsdirect.com/dremel-9...source=gba_121178&CAWELAID=161922025

Mine was similiar to this, but slightly cone shaped and about $9 at Lowes. It takes a little while, but slowly hollow out the inside of the hole you drilled until you can just start to see the threads all the way around. (WARNING!!! If you have a fear of the dentist office, this sound might make you a little uneasy haha) At this point I soaked it in PB Blaster (since there was lots of surface area for it to soak in through.

I was able to literally able to un-coil the remaining bolt threads out of one hole, the other I was forced to cut it out using a tap (it cut through about half of it, and then pushed the other half out the opposite end.

I then finished it off by running the tap through both, until it ran smoothly.

VIOLA!!! perfect original threads, no heli-coils, and no tapping to a bigger size! Now if I could only get that darn heat-riser flap un-stuck....

One thing I like to do is to use brass nuts. They are less prone to freezing up on the studs.