broken exhaust stud in header

[tab1324]

One of the studs is broken off about 1/4" out from the head so I cannot get a nut on it to clamp the exhaust flange. Any ideas on how to fix this?

Tom B.

[Ziggy Stardust]

Broken stud.

Boy....there are a lot of ways to go depending on just how much of the old stud is left exposed. Can you get a measurement of exactly how much you have to work with.

In the mean time it wouldn't hurt to get some solvents into the threads of the old stud to start loosening it up and break the corrosion that is more than likely the culprit in why the darned thing is stuck in the first place. If you can get "Mouse Milk" this would be the best. It's a special penetrating oil used for freeing stuck turbos on aircraft. Check at your local airport by asking the mechanics. The closet thing available to it in every hardware store would be "PB Blaster". It is good,, but mouse milk is better. WD40 is not good for this sort of thing.

Use a propane torch to heat up the area around the stud (not too much...try to keep the temp of the metal to under 250-300f). After it's been warmed apply the solvent. Heating the area allows the threads to open up and capillary action shoulsd tend to draw the solvent down into the threads. Tap (DO NOT HIT) the stud immediately after doing this. This helps break corrosion. Good sharp taps. Do not further damage the exposed portion of the stud. Oh....while you have that torch out.....it's not a lot of trouble to remove the gas tank and put it at a safe distance.

Let the whole thing cool. Repeat the process three or four times. This is in preparation for removing the remaining stud. Get back to me with exactly how much you have to work with; and exactly which stud on which cylinder. This will make a differece on access for tools to get in with. Hopefully it's one of the studs with not a whole lot in front of it.

Best of luck

Frank

[skids]

Re: Broken stud.

I can't hardly tie a fishing hook to the line. How do you expect me to milk a mouse?! :-)

[Ziggy Stardust]

Shame....

The mouse loves it.

Really. Mouse milk is a brand name for a penetrating oil used on freeing up aircraft turbochargers. About the best penetrating oil there is.

It's even packaged in a bottle with a cartoon of a smiling mouse;

Who wouldn't like getting milked (other than by a former spouse....of course).

Frank

[tab1324]

you can milk anything with nipples (meet the Parents)

[Ken Talbot]

Have you removed the exhaust system entirely so you can get better access to the broken stud? I'f you've got clear acces to 1/4" of stud, you might be able to crank it out with vise grips. You could also tack weld a nut onto the broken piece to get something to grip onto.

[50gary]

I have had good luck with welding on nuts to broken bolts.
First, get a nut and drill out the threads.
Second, grind the nut flat on the bottom so it seats with as much surface area to the 1/4" stud.
Third, pound (FIrmly tap) the closely drilled out nut on to the broken stud. Make sure it's straight on.
Fourth, weld the ID of the nut to the top of the broken stud.
Fifth Weld the ID of the nut to the top of the broken stud.
You may get my point, I usually have to try two or even three times to get enough weld bead to hold the torque of the wrench to remove the broken piece. I TIG weld these but a MIG should work as well?
The heat directly into the head via the stud will help to break it loose.
I had to do this one for my XS11 standard, the PO drove over something and cleaned off most of the oil filter bolt. Just one of the many reasons why I got the 78E so cheaply. Works just fine now though I did an okay job welding the nut to the oil filter bolt when I got it out I finished welded it and still use the same bolt.
Cheers, 50gary