Bubbleback thermostas, bolt broke.

[racerone]

Heating the surrounding aluminum expands it and it will lose its grip.---Aluminum expands at the rate of 0.000011" / inch / degree F which is twice the rate of steel.

 

[Fed]

Make it stop, I should have put into my post expansion rates have been taken into account.
I guess anyone who has watched a perfectly good piece of aluminium sag when heated too much would appreciate the thought of heating the bolt as an alternative.

 

[racerone]

Sorry, a good mechanic can use heat to solve a lot of problems. -- Some folks should not light a torch !!

 

[Fed]

Just fooling around racerone but it does strike me as maybe a safer way to get a lot of heat in.
I melted a pulley once and quickly learned how unforgiving aluminum is.

 

[healey8390]

No Title

Ok so I was able to drill it and run a tap through it! I was very surprised I was able to finish centered, the first hole I drilled was up a little. The threads aren't as crisp as I'd like them to be but when I put the housing on the bolt snugged up pretty good, a lot better than I thought it would . I was going to see if it would hold the recommended 60-80 inch pounds the manual states but I couldn't find my torque wrench. It's probaly gonna be a couple months before I put it back together though becuase I gotta catch up on a few bills. Thanks for the input everyone

 

[healey8390]

The parts weren't too much so I got them. When I was at my local boat shop picking them up I was telling the owner about the left head being cooler and it looks like I may not have needed to do all this work. *He said that on about 90% of bubble backs the right head runs hotter and when pistons fail on them it's usually on that side*.

Either way, it's an old motor so I'm glad I did it anyway and plus I got more familiar with the motor.