If you have a hose clamp that idea will work. I haven't bought one for decades but how much are they. 25?
Hose clamps? No, should be less than $5 ea for those big enough to go around a piston. And if they're not wide enough to cover all the rings, cover just the top ones to get them in the cylinder, then loosen the hose clamp to move it down and cover the bottom ring(s). In years past on automotive engines I've cut a beer can or coke can open and slipped the hose clamp down over it. Worked as good as a commercial compressor and a lot less $$, plus I got to drink the contents first.
