How to free a stuck piston and cylinder.

[The Buddha]

Yup, rusted shut. How do I get them freed up.
I have the thing open in my truck, been tapping the piston and squirting PB blaster.
What else.
Cool.
Srinath.

[Absolute Rescue]

I once heard that hydraulic oil is good for freeing a seized piston.

edited for spelling

[mp183]

Try Liquid Wrench, that sucker will penetrate anything.
Heat the outside of the cylinder with a heat gun.
Just don't set yourself on fire.

[ohgood]

Put a styrofome liner (hello cup) in the cylinder, and pour in some liquid nitrogen while tapping on the bottem.

Or you can just heat the cylinder with a BIG rose bud. Heat it fairly quickly so the transfer doesn't negate the process.

I prefer removing heat to adding heat. It's safer for parts, my skin (usually) and working around gas.

[nastynate6695]

we use to use kerosine. It helps to eat the rust and lubricate at the same time..       What about using that malt vinegar we talked about in the odds and ends catagory awhile back.  that should break through the rust....Or it would be a neat trick to try..

[The Buddha]

Vinegar will eat the freaking piston. Its death to aluminum. I essentially will never buy a espresso machine that doesn't have a pump just for this reason.
Put vinegar in it and say bye bye to good tasting coffee, unless you like it laced with aluminum.
We we talking about pouring in gasoline or lighter fluid and lighting it. But we scraped and sanded the bore till ti let the piston move sorta free, and then we got it out of there by wiggling, turning and fiddling it.
Mission accomplished, and now gaskets and rings are to be bought and then we're good.
Cool.
Srinath.