Garnett, It sounds like you are referring to the the "ports" or slots on the sides of the sleeve? If you put the sleeve in the crankcase you will see that one slot will line up with the exhaust port, but if you have the wrong slot lined up with the exhaust it will be miss-match. The high slot is the exhaust, and the low slot is the intake. Note that the piston has a baffle on the top. That baffle should be next to the intake slot. Then there is a groove in the cylinder head, which must be installed to interface with the baffle. If the head is miss-located to the piston, the engine will not turn over. So, here is what I use as my simple test for checking if an engine is properly assembler. If you look in the exhaust port you shouldn't be able to see the transfer port on the opposite side of the cylinder. If you can see the opposite slot, the cylinder is installed incorrectly. Also when you view the piston through the exhaust port the piston baffle should be on the far side in the sleeve. I hope this isn't too confusing.