Rusted stuck acorn caps

[mustanger]

This forum is so great! I just got a hugh problem solved that I would never have figured out myself. Thanks again joeweir1.

Now I've got a more mundane problem. I'm restoring 2 bikes cosmetically to their former glory by replacing the rusted crumby parts. As most of you probably know the 4 acorn caps on the top of the engine that hold the cylinder heads on (I think, I've never taken an engine apart and am unsure of the terminology) don't last 40 years and are always rusted raunchy vestiges of their former selves. I've got replacements for them, but I'm having trouble getting the old ones off. They screw on to a long bolt that goes deep into the engine and like I said, I've never taken one apart so I'm reluctant to give the acorn caps a strong enough twist to get them off for fear of damaging the guts of the engine down where the bolts originate. When I turn them, it seems like I'm turning the bolt that their rusted to not the cap.

Is it safe to turn these things or should I just drill them off one at a time and hope I don't damage the threads of the bolt underneath?

[joeweir1]

I just recently took acouple off a bike that sat out for 17 years and it also felt like the whole stud was turning but it wasn't.Try alittle heat first if possible.I have taken a few of these engines apart and have not had any of the studs come loose first, even on the rustiest ones.

[rbaselt]

I would avoid drilling into the nuts. There is a tool called a nut cracker or splitter selling for about $12 that might fit onto those nuts. If worse came to worst, you could remove the head studs with the nuts attached and that would give you better access to the nuts. That would be a more attractive technique if you had planned to remove the head and cylinder for a top end rebuild. If the studs do come loose, be sure to use a thread locker on the bottom ends when replacing them.

[mustanger]

Thanks a lot guys. I found a nut splitter on Ebay. I'm going to try that out when it comes in.

Happy Dreaming, everyone

[mustanger]

My nut spliter came in yesterday. I split off 2 of the nuts and could see that the bolt wasn't twisting when I unscrewed it. That gave me the courage to try unscrewing another one.

You guys are great! Do you give stock market advice too?