Stuck bolt
 

I am trying to remove the crankshaft bolt on an M103 engine without any luck. I don't physically know how to put anymore force on it and im worried about breaking something else. The engine is completely torn down except for the crankshaft. The bolt I can't remove is on the front of the crank. Any tips on removing it?

They put more than 250ft/lbs on this bolt. We use a factory crankshaft holding tool to do this. You may try borrowing a 3/4 drive impact to remove it.

Thanks for your help....I think ill let my buddies at the machine shop tackle this one.

You can place a block of wood between the crank and the engine block to stop the rotation, then use a big breaker bar with a pipe on it.

This method has never failed me.

Obviously, the socket and breaker bar have to be up to the task.
A number of sockets haved failed this particular test...

I have personally had no luck with pneumatic tools here, and wonder about the 'beating' that the percussion places on the rod bearings (if they are still in place)...