clutch problem?

[bigoggy]

i have a cen .12 engine that i got secondhand. the clutch was draging so i cut down the shoes. that stopped a lot of the problems but when i tighten up the screw that holds the bellhousing and pinion, the engine turns over as i push the car along the floor. if i loosen the bellhousing screw a half a turn the engine stops turning over and the car will free wheel. am i doing something wrong? i know the car should free wheel and not crank the engine when i push it