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Seized Pistons

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Les

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I just pulled out my second engine (out of a box full of ummmm water), and started to tear it down.

The pistons are rusted in place, not too too badly but enough. Any suggestions on popping them out ?

I've let them sit for 2 weeks with diesel oil, tried the old piece of wood and sledge, but no luck.

Thanks,
Les
 
I would try a penetrating oil like Kroil or Liquid wrench.
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PC.
 
Some times it's easy, sometimes it's not. No matter, pull the crank out so you are working with just one piston at a time. If the piston is near the bottom of the stroke drive it down with a bfh and a block of wood. If it is high, drive it up. I used Kroil over a period of a week or so. With the block in it's normal position, I added Kroil until it was covering the whole piston top then let it set over night. Next day I'd try the wood and BFH trying to get it to move just the least little bit then replace the Kroil. Once the pistons move just a little bit the Kroil gets to new rust and starts desolving the rust. Be patient so you do destroy anything
 
I have used brake cleaner on many ocassions to loosen rust parts.
 
Or, my old standby, "Marvel Mystery Oil". I've had good luck using that, but diesel usually works fairly well, too. Sometimes it just may take longer than it seems it should, so , as someone else mentioned, let patience be your guide.
Jeff
 
Oops, my mistake...I thought this was a pre-season NBA thread.
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<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by lawguy:
Oops, my mistake...I thought this was a pre-season NBA thread.
wink.gif
<hr></blockquote>

Might want to soak some of them in Kroil or Liquid Wrench too. You can't be too careful.
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https://www.kanolabs.com/
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PC.
 
Les,

If you need a hand with the sledge hammer I'm happy to give you a hand.

[ 10-10-2003: Message edited by: Mark Jones ]</p>
 
Bottle jack, socket or pipe of right dia and length, 4x4 and strongest header beam in your garage. Get help holding the 4x4 until you get pressure
 
Thanks for the replies. I was originally concerned with using to much force and wrecking something.

Anyway, I got 2 of 4 out and I'm drunk so I'll wait till the morning.

Mark, maybe you could come over with your B and I could um ahh borrow some parts.

Does anyone have any suggestions on a good book for info/steps to rebuilding one of these engines ? I've got the basic idea, but then I hear things like balancing, etc.

Thanks,
Les
 
I have heard that dry ice will shrink a piston just enough to break any rust sieze. Have not tried it so can't speak from experience.
 
May sound wierd, but I remember my dad using COCA-COLA to loosen the rust on an old Ford motor to get the pistons out. Worked great but you know what it does to your guts. This Les, is unless you are using COCA-COLA for mix, then chase it with a good bottle of KEITHS ALE too.

Paul
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by KLUTZ:
May sound wierd, but I remember my dad using COCA-COLA to loosen the rust on an old Ford motor to get the pistons out. ...
<hr></blockquote>
Same story here. I remember my father using Coke to loosen the heads on a Packard V-12. He was always afraid to actually drink it.

Re freeing stuck pistons - lots of good suggestions here. My own most successful method is similar to BOXoROCKS' comment. I form a kind of press using 2 long pieces of angle stock, one under the engine (protect the mating surface where the pan meets it) and one on top. Two 36" threaded rods connect them. I use a round piece of wood about 7" long to bear on the piston. I thread the nuts tight on the rods and pour some K1 and Mystery oil into the cylinder and leave it overnight. The I just keep tightening it and rapping it once in a while. A bottle jack would probably work with a similar setup.

The strangest method I've heard (Please don't try it) is to put burning charcoal in the cylinder and leaving it a while. This was related to stuck tractor or stationary engines.
 
Grahams' suggestion is a good one (dry ice inside the piston). I had a stuck one that I was able to free by turning the block upside down, filling the piston with ice (regular H20 type) and, after a 5 minute wait, pounding away with a wooden hammer handle & BFH.
Prior to this I had used all the previously suggested lubricants, etc.
 
I have used Coke a Cola as well and successfully.I like the dry ice idea and maybe just after soaking with coke this would help.You will still need to hit it using a block of wood between the hammer and piston.And people wonder why I don't drink coke.
Good luck.
 
Coca cola used to work just fine out here but a few years back now the food people made them change the formula, it don't work the same now. I have used vinegar to free some rusted bits fairly successfully. Good luck,and I like the dry ice idea, its what you use to shrink the valve guides into the aluminium casting on an XK jag engine. What I use anyway.
 
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