Yes good old stupidity kicked in while reinstalling my strut bar and I crossthreaded one of the mounting bolts. What's the method for fixing my blunder?

 

you will have to pound out the bolt with a hammer...should fall right out in the fender well....go to nissan and pick up a new nut and bolt and re-install...then wal...laa

 

WTF? illudezion, sorry, I don't know you, but that has to be the worst advise to give a person. If it has a nut on the other side, get a nut splitter and cut the thing off, and the bolt will pop right out. If it is threaded into a mount, try and back it out. If it won't, you will have to drill it out and retap the threads on the mount. Pounding on it with a hammer could lead to you causing fractures in the metal, possibly leading it to fail in the future.

 

How far in did you thread the bolt before you realized that you cross-threaded it? I would suggest that you get a metric tap and die set (sorry, I don't know the exact sizes needed). Use the die to "fix" the treads on the bolt and the tap to "fix" the treads onto the strut tower. Keep in mind that this is really only going to allow you to properly re-tread the bolt. The threads that you fix will only have limited holding power which is why I asded how far in you treaded it. I doubt that you got it threaded in the whole way though.

 

Pat, we've all done it, cursed it, vowed to never do it again, and done it again.

Since you did say "bolt" (1 of 3 per side) and not "stud" (1 per side), I mostly agree with teh215.
Replace the bolt. Your problem is with the threads in the hole. If you have at least three undamaged threads in the hole, use a taper tap to CAREFULLY restart the threads to the original/correct alignment...the axis of the tap should be align with the axis of the other two bolts. It is very easy to pick up the crossthrd alignment if you're not careful.

If you don't have three good threads in the hole, go the non-locking helicoil solution. We'll cross that bridge if you need.

 

The general rule we use at work on threaded holes is that you want as many threads gripping the bolt as the outside diameter of the bolt being installed. For example, with a 3/8 diameter bolt, you want at least 3/8" of thread engagement. Now, I cant remember how big the OD on the bolt is in question nor how deep the threaded hole is.

 

zach, that's a good rule of thumb, especially for bolts in tension.
This is a 10mm hole (about 3/8 fine thrd). One bolt diameters worth of thrds is about 8 thrds. Since this bolt/hole is largely in shear, and has three other siblings per side, I thought 3 thrds minimum would be safe.

 

I did forget about the 3 other bolts securing that side down.