The head bolts are 12pt 7/16. I don't know if that's typical. I could't break them free with what I had available at the time. It seems like the only thing I have that will fit in the limited space and have a chance of breaking them free is a box wrench. They seem to be somewhat corroded from sitting for 20 plus years. I'm doing the rebuild in my studio and most of my tools are at home, including my box wrenches. I'll try it again tomorrow.

Is there any trick to making this a little easier? I was thinking of heating the head with my acetylene torch but I don't want to take a chance on damaging the heads. It seems to me that it should be effective. Aluminum has twice the thermal expansion coefficient of steel. Like I said, I don't want to take chances.

 

No heat as the bolts are in steel thread insert in the heads and the 12 point are an aftermarket headbolt kit stock was 9/16" hex heads. Hit up Amazon or a tool supply place for a set of these. They are called torque adapters , must have for doing a shovel upper end correctly and makes getting in tight places an retorquing much easier.

 

Building up the tool collection. This can get expensive.

 

I've made do for years with manifold and starter wrenches (a curved box end wrench). I have several different bends and one usually fits the space.

 

Torque sadapters are the way to go. And the nice thing is that you can use a breaker bar to get some leverage to break them loose.

 

I took it apart with a variation of box wrenches and sockets. I prefer to be able to use my torque wrench reliably in the assembly. Or maybe I'm just rationalizing my need for shiny new tools. Either way, I got my fix.

 

If you can get your 12Pt box wrench on the bolt, you can take another box end wrench, and mate the box end to the open end on the main wrench and use that as leverage. In essence, making a longer lever. I do this a lot when I need just a bit more torque.

Excuse the drawing