Pistons Are Rusted Stuck.

Just to avoid any misunderstanding: 180 PSI on a 3.5 inch piston creates a total force of 1732 pounds (not PSI) trying to push the piston down. Same as if you removed the head and stacked 1732 pounds of cement blocks on the piston. I was simply trying to point out that it's not surprising the piston moved, not that you were doing anything foolish. Quite the contrary. Most modern engines will produce 150 PSI just cranking, and many times that when running under load. So your 180 PSI was simply a brilliant solution without any danger of damaging anything. I'd like to believe I would have thought of it. Ha!

FWIW, just today I got the stuck pistons in my 2 cylinder gasoline John Deere 420 crawler engine to let go after soaking them with Kroil for 4 or 5 days. I was able to turn the crankshaft with a foot long bar to break them loose. Looks like no damage to the bores. If I hadn't already removed the head I would have been fabricating an air hose adapter after reading your post.

 

No problems on this end. Just a late night as usual. Sounds like your pretty handy yourself. Jeep or not this is a good place to hang out.

 

Oh, I have a Jeep alright:

 

Too funny! I didn't see it in your information and I had already saved that picture from that thread. Watch your 6... I like. My mostly garage queen at this point.

 

Used to spend summers at my great uncles farm when I was in grade school. He could fix anything. He took an old tractor that had been sitting in the woods with the engine locked up and bet a friend he could get it started. He put the Marvel Mystery oil in the spark plug holes for a week or two. The deal was he couldn't open up the engine. Each day he would take the breaker bar and socket and try to work it back and forth and add some more MM. One day he got it to move and told his friend to bring a battery. He cranked it there in the woods and won the bet.
He had built a metal tank that bolted together with rubber gaskets around the flanges. He would put rusted parts he could not get apart in the tank in diesel fuel and Marvel Mystery Oil and it had an air fitting on it. He would add air and pressurize the tank and let it sit.
He said after a while it would soak through and he could get it to break free. I used to take things to him to fix I couldn't get apart.

Glad you got the pistons out.


Dave

 

That is a good story. Was wondering about the pressure on the tank, though. The only thing I could come up with is that it would fill any voids. That works for me.
Old guys rock sometimes! They worked with what they had and it wasn't much.

 

Uncle Phillip always made stuff from nothing.
He had a forge and made his own chisels. He would tell me the color to quench it for different hardness.
He had the top part of a old wood lathe and made the rest of it and made baseball bats for all of us kids.
He had a powder wedge that he drove into an ash tree and lit the black powder and it split the tree into quarters and he turned out the bats. Bats for the boys and rolling pins for the girls.
When I was about 10, for my birthday he let me disassemble an old truck for them to make into a hay wagon. Boy was that fun.

Dave