Here's some techniques my (old) uncles have used on the old tractors they would unstick. My one uncle took an old spark plug and hollowed all of the ceramic out of it and welded in a grease zerk. He then filled a cylinder with oil (with the valves closed) and started pumping oil through the zerk-equipped plug until he felt movement or felt damage may occur with more pressure. He would work at it for days if the engine was stuck bad.
My other uncle made an adapter for the sparkplug hole to fit his hydraulics from his tractor. He would hook up one cylinder at a time until the cylinder would move and then go to the next one .The last one you would have to stand back. When the last one broke loose, oil blew everywhere when the engine spins over.
These methods were done on tractors, I definately would'nt do the second one on a truck/car engine. The first one seems more controlled though, and maybe worth a try someday.
Scott
