Stuck B piston

I'm working on a 1950 B John Deere. This is the gas engine, not an all fuel. It's got aluminum pistons. One piston is stuck and won't move with conventional methods. I've tried soaking with PB Blaster, ATF & gas mixture, and MMO. Then, used a big hammer and block of stove wood. It don't move. Now, I can heat it, or put it in a big press. In other words, I CAN GET IT OUT. I'm sure it will need to be bored,but, I'm not wanting to destroy the piston, or anything else if I can help it. Does anybody have any suggestion or experience with this. Thanks in advance. Todd.
 
If it has to be bored, that piston will be too small anyway. Do what you have to. But I would heat it to expand then cool it with water to shrink it & maybe it will break loose.
 
What works for me is I stand the block up and pour some deisel in the bore ,lite it and let it burn till it goes out.Watch and see if you see any drainage dripping past the piston on the grd if not repeat.When you do see something dripping that is the time to tap the piston.Done a bunch and dont have to do a lot of beating.As for the amount it doesnt take a lot to burn 5 or ten minutes so go conservatively there.Couple of oz. first
 
Todd,
Odds are pretty good that if it's stuck that bad it's not going to just cleanup with a little honeing so you will probably have to bored and has been said that piston won't fit anymore. What does the other one measure. It may have been bored already since it has aluminum pistons which means it's not original. Just be carefull not to break the block. The pistons are not super expensive. Good Luck, John
 
Just my 2 cents: I recently talked with another 2-cylinder enthusiast, who said that they welded up a fitting to put a grease fitting into the spark plug hole, and with the head (or equivalent) torqued down good, they just pumped grease until it forced the piston down without breaking anything. One other point, I had a Ford V-8 with new, expensive aftermarket pistons. The cylinder wall of one cylinder got damaged by foreign material that got in there. Anyway, my machinist removed the piston, bored it enough to put in an iron sleave, then put in a piston the exact same size as the others. Never had another problem out of it. Ie, there are ways to restore your cylinder without replacing the piston, if it is not too far gone. Hugh
 
Todd,
Looks like you are getting a lot of good advice on here. Here is a little more.
Another method is to make up a steel plate with holes to match four or five of the studs, place a block of wood of proper size and shape on top of the piston, place your plate on the studs and block, and use the nuts to put the push on it. The wood block should be end grain to the piston and plate. When you get a strain on it, smack it with your best (biggest) beater. Something has to happen. I would think a minimum of 1/2" plate. Good luck. VH
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top