Thanks for the help.

One is Russian can't remember the name right now, the other is Chinese and the manual that came with it only says 2.47cc. I got them from Carlson Imports and their site has been down since I got them so I can't get any specifics.

The manual that came with the Chinese one said the first thing I should do is take it apart, clean everything, and lube it before starting. During this process I took out the screw since I didn't know any better.

The weird thing is that the screw now won't even touch the contra piston, just spins until it is fully screwed in. Can the contra piston be pushed down too far and not come back?

Thanks again,

Canabian