I use a product called PB Blaster (you might already know about it)
PB Blaster Penetrating Catalyst, Loosen rusted bolts and fasteners
I find that spraying it on, then tapping extensively on the bolt and all around it - then let it SIT - 24 hours.(You can spray it a few more times and tap)....then try to work it out - haven't had a case yet where I couldn't remove one - sometimes you do need heat however....
Wherewolf
PB Blaster Penetrating Catalyst, Loosen rusted bolts and fasteners
I find that spraying it on, then tapping extensively on the bolt and all around it - then let it SIT - 24 hours.(You can spray it a few more times and tap)....then try to work it out - haven't had a case yet where I couldn't remove one - sometimes you do need heat however....
Wherewolf