The problem with ring compressors intended for automobiles, is that on F engine and later lawnboys, there is no head, the cylinder and head and 1/2 the crankcase are all one piece. You have to go in thru the crankcase, and if you want to keep the piston and rod attached to the crank, the only way to insert the piston into the cylinder is with a very small type of ring compressor. A hose clamp fits the bill quite nicely, in absence of lawnboys discontinued ring compressor tool. Once the piston is slid in far enough to capture the rings, you can unscrew the hose clamp completely and remove it easily.