Well, over the last few weeks in my spare time I removed 4 very stuck pistons from a Crosley block. I thought you all might like to hear what I did since it took 3 different techniques to get all 4 out. I saved the block and broke 2 pistons. For years I have told people to use a spark plug/grease fitting adapter to pump grease in to the cylinder to push the piston out. This has worked for many people over the years, it just takes a couple of tubes of grease and you build up your arm muscles. After soaking the cylinders in penetrating oil for a few days I started pumping grease. Number one cylinder came out till I got to the last 1/4 inch and the piston cocked sideways and the grease came out ant the piston was wedged. I ended up breaking the skirt on the piston getting it loose. Cylinder 2-4 had valves burned so bad the grease came out the exhaust ports. Plan two a slide hammer attached to the rod studs. After way to much hammering I got number two out. Piston 3-4 would not budge with the slide hammer. Plan number 3, I build a jig that bolts to the rod studs 4 threaded holes to put long bolts in and a some narrow steel plates to lay across the block to push on with the bolts when you thread them threw the rod plate. This was slow but worked. I would crank down on the bolts in sequence till I ran out of bolt, then crank them back out and add some more spacer plates and do it all over again. Number 3 came out fine, piston 4 wedged as it was just clearing the cylinder. I drove out the wrist pin and removed the rod and broke the piston trying to get it on jammed. Well that's my story and I'm sticking to it. Any of you have a different trick to remove stuck pistons?

For stuck or burnt valves--Make a steel or alum plate to cover the exhaust & Intake ports. Bolt this plate using the studs in the cyl. Use an old gasket to seal,Pump cyl with grease-push piston out. It does WORK.

Thanks Chuck, I was going to make a plate for the exhaust ports, hopping that the valve guides would hold, but I talked to a friend that restores really old cars (pre 1915) and he suggested the puller idea so I decided to try it. He had used the puller idea on a 1910 Chase with success. 

Someone once told me about filling piston with dry ice and pulling or pumping out..to save arm can get air powered grease gun!!