Cyborg,


Getting the sleeve out to disassemble the engine, should be possible after heating the engine in an oven, for 20 minutes, at about 180 degrees C.

Do it after first removing the head, the back-plate and all loose parts.

When it is hot, turn it so the piston is at BDC, from inside the cylinder, stick a small piece of wood in the exhaust port, turn the engine and the piston will push the sleeve up far enough, so you could pull it out completely.

Mark the back side of the connecting rod and un-hook it from the crank-pin, to remove the piston+rod assembly.

Allow the engine to cool completely and push out the crankshaft; it should come out alone, without the rear bearing.

Heat the crankcase again, so the bearings would drop, or be popped out, by wrapping the rear of the engine on a piece of wood (rear bearing) and the front bearing is pushed out (forward) with a wood dowel.