Hole in crankshaft snout.
 

Bob, the 120 I am overhauling has a hole in the snout, where the prop stud goes. Well, not a hole but it is cracked and broken, looks like when it was drilled it only had a few thou thickness left and it has broken through. I know you are supposed to leave the stud loose, so that means a leak.

What do you recommend I fill the area with? JB Weld?

RE: Hole in crankshaft snout.
 

Is the end of the actual crankshaft chipped or cracked? (outside of the threaded portion?).

If it is a small crack or hole, dont worry much about it. But make sure the drive collar fits over it properly and that the prop drive seats properly.

The threaded section of crankshaft does not pass through no way it can leak to the crankcase even if the stud is completely removed. So no threat in that respect.

Bob

RE: Hole in crankshaft snout.
 

Well, that is indeed the problem. The hole, when drilled, left only a few thousandths of a 'wall' and it has cracked and broken through. The photos are taken with a small LED inspection light shining through the opening.

So what do you suggest? JB Weld? Will JB Weld hold up under heat and pressure?

RE: Hole in crankshaft snout.
 

OHHHHHHHHHHHHHHHh.............................

Yeah, thats lookin weird.

This is for the big-block 120 .... (old type cast case) correct?

Hold of on the JB for a moment... let me check with Dub

Bob

RE: Hole in crankshaft snout.
 

Ok

a bit of JB installed from the prop stud side will work ok.

I checked with Dub ..... it comes from trying to make the thing a light-as-possible.

He offered to fix it if you want .. but likely you can handle this ok.

RE: Hole in crankshaft snout.
 

Thanks Bob. JB it is! :)