ORIGINAL: jedijody
Martin, the piston cannot hit the top of the head, it's probably hitting the piece of bearing cage or roller that got left in the engine after the initial repair. You should be able to feel this as you turn the engine over with out the spark plug installed, as the piston comes to TDC you will feel slight resistance then with a little more pressure it will go over TDC. If the crankshaft bearings feel tight, there is no end play in the crankshaft, and there is nothing leaking from the main bearings, you should not need to remove the prop hub or crankshaft. I would carefuly inspect the bearing on the big end of the rod by using some magnification and turning the bearing around the crank throw with a small screw driver through the oil slot in the rod. If anything looks marginal continue with the disassembly.
Thanks. I still have the prop hub assembly not running in the center so I'll disassemble it.
Will take the plug out and see if it blocks anywhere. What I noticed is that one half of the cylinder head is completely clear from carbon and I have a blank spot on the piston, see image.
I checked the cage roller really well by turning the crank slowly and couldn't find any irregularities. Also the front and rear bearing seem to be in perfect shape.
TBC...
And unit53, yes I could send it in but Jody would have to go through the same procedure and the last missing tool is the piece of metal to hold the prop hub. I always mount my hardware to outlast the frame of the plane and I can do this repair w/o taking the engine from the stands, and taking off the choke and throttle linkages, and I still have the header in place on the cylinder. Messing w/ the header too much can eventually cause it to start leaking, stripped threads etc. Now I only need to replace the cylinder gasket. And I think something is wrong with the prop bolt. I'll find out soon.