Crankshaft/Piston Binding Problem

I have been rebuilding my 1956 Johnson 10hp from top to bottom over the winter as time permitted. I got the crankcase cover installed today and ran into an issue when trying to rotate the crankshaft. Upper piston will rise in the cylinder when the crankshaft, but binds when the top of the piston is still 3/4 inch short of TDC. Same thing when the crankshaft is rotated the other way. The same thing happens with the lower piston.

Any suggestions on what to look for when I pull the crankcase cover off again?

Removed the crankcase cover today. Didn't take long to find the problem, but the question is why. When the lower piston is in the down stroke, the bottom of the piston skirt is bottoming out on
the lip/flange at the bottom of the cylinder.

I'm not experienced with outboard motor rebuilding but do you think there is a chance the pistons are rotated 180 deg . maybe set the head in place to verify the location of the dome on the pistons ?

Like has been mentioned the pistons have to be oriented correctly. Pappy outlined on this particular model how they go. Other mfgs have arrows etc that point toward the front etc.

Obviously you are going to have to crack it back apart.

You are right , pappy did mention upside down pistons , I apologize , I missed that , I try hard not be " that " person that can't read all the posts before hitting the keyboard . Keep us updated on the solution please . Thanks .

Sorry for the delay in getting back to this. March was a very rough month for me.
T
Turned out to be a totally different problem then I originally thought. The shaft of the connecting rods is offset from the center line of the rod to provide clearance to the counter weights mounted on the side of each crank journal. I had the Pistons installed in the wrong cylinders and the connecting rod shafts were binding against the counter weights.