Topic: exhaust mounting studs - removal

[Tugboat]

Just got my KZ400 back on the road after replacing the exhaust & airbox + cleaning carbs this winter. One of the studs that the exhaust collars mount to is partially stripped, so that the nut won't tighten more than a certain amount, causing an exhaust leak where the header meets the head. I've got a replacement stud, but am wondering what the best way to remove the old one is without torquing it off. Just grab it with vice grips and go at it? Hit it with some WD40 first? Whatcha think?

[Laminar]

If you can, put two nuts on it and tighten them together, then use those to unscrew it from the head. That's the method I've heard for removing head studs.

[Tim.]

In the meantime, if you want to snug it down, you might be able to put a couple/few washers under the nut so it remains in the threaded area of the stud.  Not sure how long the stud is, or how much of it is stripped.

[BlindJoe]

heat helps

[immortal]

I found that if you start the double nut method and get both nuts in place and ready to go then...heat the casting around the stud REALLY HOT with a propane torch, then spray the area with WD40, it should loosen things up enough for removal.  You can tell if it was hot enough by the smoke filling the air. Then crank on the nuts and they should turn with no problem at all.  I think the the combination of heat enhanced capillary action and the shock of rapid cooling does the trick. If you have a propane torch I would do it that way...if you don't and try the double nut method on its own you may get lucky but I am convinced the heat makes the world of difference!