removing rust bolts

[Tadams]

I need to replace the exhaust pipes from the manifold to the rear and they are really rusty. The pipes fell apart when I started to remove them to rebuild the transmission. Is there a good or preferred way to do this without braking the bolts? I used a nut buster product yesterday and thought I would spray them again today and maybe try to remove them in the morning.
While at the farmers market this morning I overheard a man who is working on a 55 corvette who said if you sprayed brake fluid on the old rusty bolts and let it sit for a couple of days you could remove any rusty bolts easily. Has any one tried that or have any other ideas?
as always, THANKS FOR YOUR HELP.

 

[Bad Sport]

Are they bolts or studs? If they are bolts I would just cut them and replace with stainless bolts.

 

[RustyRatRod]

PBlaster. It works great.

 

[JLP]

PBlaster. It works great.

X2, spray on let sit for about 8 hours spray again, let sit over night, sray one more time, should be good to go. Heat with a torch if needed (DO NOT HEAT AND SPRAY AT THE SAME TIME). Took my 67 Barracuda apart this way after it sat outside for 10-12 years (I live in NW Oregon to let you know how rusted the bolts were).

 

[Bad Sport]

I guess they must be studs then, I wouldn't waste my time if they were straight through bolts.

 

[RustyRatRod]

Tapping on them while they are soaked to the bone also helps to get the penetrant in too.

 

[Tadams]

Sorry I didn't get back on sooner.Its canning green bean time. These are the bolts that screw on the studs at the end off the manifold. They are really rusty,but hopfully I can remove them with out breaking the studs. That would make life a lot easier. Thanks for your help.

 

[daredevil]

I use a homemade concoction that I think is as good or better than pb blaster. 50/50 mix of acetone and trans fluid. Acetone etches into cracks and trans fluid lubes. Try it sometime. Just be careful around paint.

 

[Tadams]

I used PB Blaster and the bolts came out very easily. I sprayed and let it sit for several days. Didn't break anything. Thanks for your advice. Now I can start cleaning up the rusty underneath of the car.
thanks again