Reply To: Can I apply heat to head bolt? Johnson RDE-17 1955 25 hp

[frankr]

My 2c, I have removed many thousands of such bolts. And, admittedly, busted off a few also. My take on the subject is that most people are far too timid, and afraid of damaging something.

But nevertheless, I use heat. HOT heat, like from an acetylene torch. Propane usually is not hot enough. Heat the aluminum around the bolt, not the bolt. That expands the aluminum, loosening it’s grip on the steel bolt. While it is very hot, but short of melting, quickly remove the bolt (yes with air wrench).

Warp the head??? Not to fret, you were going to clean it up and resurface it anyway—weren’t you?

Good luck.