Rusty Bolts?

[thegoat4]

I pull the y-pipe because I figure why fight with it when I can just win? Besides, with it out I can inspect it, the cats, and the o2 sensors to see if anything fishy is going on.

Procedure for stuck bolts: use an impact I know is too small and rattle on the bolt a while. It shakes crud off the exposed threads on the back side so they don't hang up on the way through. Sometimes the little impact will take them out. Then, if room allows, heat the bolt head until glowing red and let it cool back down for a minute. Most of the time the bolt will come loose after that. Then soak it down with PB and wail on it with the big impact. Switch between forward and reverse every few seconds.

That's worked on everything from 1/4" to 1 1/2" bolts for me. Only a problem when the bolt is completely rotten, then the small impact I used first typically shatters it. Same for studs, but wire brush the exposed threads first.

 

[cocoasranger]

I worked in a muffler shop for years. We always heated the nuts on the end of the studs orange (while trying not to heat the stud any more than possible),then spun them off with an air gun ( or by hand for the shackier ones).

For the studs, we heated the manifold flange to orange ( again without heating the stud much) and spun it out with a stud extractor socket. We did thousands, and it worked virtually every time.

However, there was this one time when a tech pulled on a headpipe to show the customer it was loose, and the manifold broke in two and fell on the ground. That was awkward.