I checked on the stuck cylinder today and it still had the same amount of fluid as it did before. The 903cc engine was still not budging. I soaked all of the liquid out of the top of the cylinder and put some automatic transmission fluid into it. I have been researching ways to free a stuck engine and ATF was one thing that kept popping up. There were some other remedies out there as well. Some of them seem way out there. There was more than one that instructed to create a concoction of different fluids let is soak for a few days, putting a cloth rag into it then setting the rag on fire. I guess the idea here is to heat it up enough to let the piston move a little. There was another that suggesting pumping grease into the cylinder, with the head still on but the block and head removed together, until the piston was forced out by the ever increasing pressure from the grease.
All of the sites that I read did have one or two commonalities. The main secret being patience. Another common theme has been to take the block off the engine so I can try to move it upwards and downwards. It would also allow penetrating oil to be applied from the bottom. Lastly, is to be smart about the pounding you do on the piston so you do not damage the piston, the cylinder walls or the connecting rod.
I guess I will have to rely on patience as I found out that the second engine I have is the 843cc engine that Fiat used in 850s. After reading and asking some questions on the Fiat 850 Yahoo group, I found out that the only real difference in the two engines is the stroke and the bolt pattern for the water pump. The 843cc has a 3 bolt pattern where the 903cc has a 4 bolt pattern. Since the stroke is longer on the 903cc I am assuming the block is a little taller but the pistons should be the same. As long as I don’t damage the connecting rod, or the cylinder walls, I should be OK.
I did get a gasket kit from a guy on the Fiat 850 Yahoo group that appears to have all the gaskets I will need. I got the kit for a great price so even if there are a few that I have to track down and buy separately I should still come out ahead.
Here are some links for freeing up a stuck engine that I found useful.