Broken Head bolt cannot remove head?

[rude70]

I am trying to remove the port side head on a 1975 115HP because the spark plug thread has stripped in No 4. I have removed all bols except for No.2 (the middle inner bolt see photo). The head of the bolt snapped off so if I can get the head off I should be able to use stilsons to get the bolt out. Both pistons are down and I can rotate the head slightly by tapping with a hammer an block of wood. Looks like corrosion between the bolt and head. I am soking penetraiting fluid, but there is no obvious leavering point to get the head off. Do I have to apply heat to the head and then tap it?
Any help appreciated.
Thanks

Richard

 

[Chris1956]

Re: Broken Head bolt cannot remove head?

Gee- I would think you are on the right track. The headbolt should pull thru the head, eventually. Penetrating oil is fine.

Remember to heat the bolt stud when you are going to turn it out, and good luck with it.