Exhaust Bolt Removal

[AeroNautical]

I honestly try to use the search, but maaan, it sucks.

 

I'm doing a tranny swap, in order to do this I need to remove the section of exhaust pipe that runs from the manifold to the catalytic converter. I'm terrified to do this, however. There is no rust, but the bolts connecting it to the manifold seem rough and brittle, not surprising considering the heat they put up with. I REALLY don't want to snap it, because an exhaust leak would stop my MJ dead in the water. My questions are: Are these bolts, or studs? How can I somewhat safely remove them, PB blaster can only do so much. I figure if they are bolts, they can be replaced, but studs.... I hate them with a passion. 

[jimoshel]

Not sure if there was a standard or not as I've found both when removing the exhaust. What I do is clean the threads real good with a wire brush. Soak it good with rust blaster, Let set for awhile. Then try using a regular wrench, generally a rachet with a long extension. If it doesn't come loose then use a impact wrench. Have the wrench set at it lowest setting. To where it just barely rattles. The steady hammering will break the rust and the nut loose.

[Tactical Bacon]

Day 1. PB Blaster it that morning. PB Blaster it in the evening.
Day 2. PB Blaster it in the morning. Start work that afternoon. PB Blaster it, wait 30 minutes, blast it again and then start working. Do what jimoshel said about hand wrench and then impact.

You can also try the loctite freeze break-free. Supposed to be wonderful.

[cruiser54]

Day 1. PB Blaster it that morning. PB Blaster it in the evening.

Day 2. PB Blaster it in the morning. Start work that afternoon. PB Blaster it, wait 30 minutes, blast it again and then start working. Do what jimoshel said about hand wrench and then impact.

 

You can also try the loctite freeze break-free. Supposed to be wonderful.

That freezing stuff is GREAT!

 

OP, when the nut starts to loosen, tighten it back in a few threads, and then proceed to remove it.

[jimoshel]

Another thing that should be mentioned. When trying to bust a rusted nut or bolt loose, try going the other way with it. Turn it clock wise. Won't take much, just feel it break loose. Once you break it loose soak the threads with PB Blaster and keep rocking the nut. For some reason the rust breaks easier when turned on instead of off.

[AeroNautical]

Happy to report it all went well thanks to your suggestions. Soaked the bolts in pb blaster, used that bolt freezer, etc. None of the bolts were rusted, but they were torqued so tight I almost broke a breaker bar trying to get one off. 

[Comanchemodder]

I changed all my manifold bolts to Stainless steel.  Seems to work ok.