Trim motor-seized bolts

[Mrsnaper]

TRIM MOTOR HAS 3 SEIZED BOLTS- WILL NOT TURN
Is there any miracle lubricant to loosen up these trim motor bolts? We already put heat on the assembly, got it fairly hot and nothing, bolts wont turn. Its a 2004 Yamaha 115txrc and
these bolts feel like they will snap clean off if I put too much pressure. I'm just trying to get
inside this motor to see if i can replace the brushes. Any help will be appreciated.
Any tricks out there to loosen up corroded bolts? Thanks!

[PotomacSouth]

Had that happen to my yamaha 150s. I ended up snapping 5 bolts off. I was doing both motors at the same time. I think the SS bolts are really soft on those motors. It doesn't take much to break them. i ended up taking them to a friend who got a couple out by welding a nut to them. The rest I had to drill out.

[lemaymiami]

-Now you know why a really competent marine mechanic is worth finding... If everything on a marine motor dis-assembled and assembled without fighting you we would all be working on our own gear. I watched my mechanic one day work for a solid hour to drill out one bolt that had snapped off of my starter... Typically they'll snap on you 'cause they're frozen, but the metal is very hard to drill... Hope someone finds a magic formula for you - but I'd bet against it... Aren't boats fun?

[Joe]

I'd soak it (if possible) in PB blaster. If you can't get it turn with that..it probably won;t come out in one piece.

[PF-88]

In my experience if a frozen bolt won't budge when you heat the surrounding base metal, it's not coming out. Soak it with penetrant for a couple of days, I like "liguid wrench" and hope for the best but your probably end up drilling and tapping, good luck.

[CMEBoston]

Heat.