I have a "new" style B-40 (about 5 years old, maybe more) with a broken muffler mount lug on the case. One lug is fine, other cracked in a crash. Attempted repair with JB Weld was not successful. I now see Brodak claims it has the B-40 case in stock for about $40, which solves my problem if I can get the engine apart and back together.

Any recommendations for properly disassembling and reassembling this motor without damaging anything? I have not tried yet, just researching to see if makes sense to attempt it.

Thanks Pete, I'll have a look. But what is "Youtube?"

Thanks also to the several folks who sent me helpful PMs.

For a blow by blow.

1-Put a prop on the engine.
2-loosen the head bolts one at a time about an 1/8 of a turn going criss cross.
3-Remove the head bolts and the head.
4-Place a glow plug gasket on top of the piston to where it just sticks into the exhaust port of the sleeve.
5-Rotate prop to push the the sleeve out far enough that you can grab it and pull it out. (you may need to heat the case).
6-Mark the front of the piston with magic marker so that you can put it back the same way.
7-Remove the back plate and slip the rod off of the crank pin and remove the piston and rod.
8-Remove the prop and prop driver from the shaft and pull the shaft out.

That should get all but the needle and spray bar out of the case so you can start installing the parts in the new case.
Every thing should go back in reverse order. Pay attention to the orientation of the sleeve so that the highest port goes to the exhaust.
When installing the head just run the screws down to where they touch the head, and then tighten each one in a criss cross pattern a little at a time.
If you have questions come back here and ask cause I may have forgotten something.

I use a toaster oven instead of a torch.

Aki