Removal of cam journal cap bolts

[Chuck Hahn]

So these bolts seem to be way way tight and I stopped trying to take them out for fear of snapping one off in the head. Any suggestions on how to crack them loose without snapping one off?? I was thinking heat the are best I can with some MAPP gas and then see if they break loose??? Also i was told they arent the best bolts to begin with, so what would be good replacement bolts?? Any links to new better bolts would be much appreciated.

79 CB750

 

[Chuck Hahn]

OK.... I have the MAPP gas out ready for some destruction !!! Anyone got any last minute advice before i get all jiggy on this head???

 

[Chuck Hahn]

Should I just go buy a 90 degree drill and some left handed drill bits and not care if i snap a bunch off...then drill out the pieces??

 

[amc49]

You won't likely be able to (your prevailing mood figures in greatly there) drill straight enough to not ruin the head. The torch will likely swell the aluminum up to tighten the bolts even more, it swells at 3X the steel rate. Most people are in parts butchering mode by then anyway and that makes it worse.

All you can do is to unloosen the bolts the normal way and cross your fingers, a bunch of them break clean to be able to back the broken piece out easy but again if you get too rambunctious about it you will take something that works with patience and turn it into an ultimate horror story. Left handed bits may work well.

http://www.cb750c.com/modules.php?name=Forums&file=viewtopic&t=25656

Go there and register to get in for free and the better bolts at that post from the guy there 'genesound', tell him I sent you. He also sells the better quality viton valve seals as well and both parts at rock bottom prices.

 

[Chuck Hahn]

Im not yet in to grabbing a hammer mode. Ive used left handed bit a lot..mostly on broke off exhaust header bolts. Seems once you drill a small pilot hole and progressively work up in sizes the remaining stud threads will eventually spin themselves out. And I am very aware of patience being my friend when doing it.