how do I remove stuck/frozen pistons..

[Armond]

I inherited a 72Tii block and the pistons are frozen. Previous owner had it stored outside and exposed to the elements for over 5 years or more."surface" rust is also visible from looking at the top of the cylinder walls. Any advice would be greatly appreciated. TIA.

[Arky2002]

you do not say if the head is on or if the cylinders are exposed. so I will reply as if the head is on: Remove the spark plugs, pour a couple of Marvel Mystery Oil or squirt a few seconds of PB Blaster in each cylinder and let sit overnight. If the engine is in a car, hook up a battery and see if it will turn over. if not, use an impact wrench on the bolt at the front of the engine and see if it will turn over. If it doesn't, remove the crankshaft and hammer wit a bfh on the cylinders using a cut off baseball bat to transmit the impact.

get back to me if that does not work

[Armond]

head is off and the cylinders are exposed. Sorry my bad.

[Guest Anonymous]

I inherited a 72Tii block and the pistons are frozen. Previous owner had it stored outside and exposed to the elements for over 5 years or more."surface" rust is also visible from looking at the top of the cylinder walls. Any advice would be greatly appreciated. TIA.

There is no mystery here common sense prevails. Try to oil the cylinders and pistons as best you can and try to turn crank to loosen things up. If things are really rusted unfasten the rod bolts and try using a thick wooden dowel on the bottom sides of each piston to pop them up (the opposite of installation). If things seem hopeless, haul the block to a machine shop and let them try a hydraulic press on things.

hth.

[1972fritz]

if there iss that much rust where there stuck the block will need to be bored hence new pistons so it really doesnt matter how you peel beat or break them out you dont need to worry about messing the side of the cylinder up putt the crank get a big pipe and beat the shit out of them. try not to work over the rods you can save yourself some money there.

[dlmrun2002]

Kerosene if nothing else works..

dlm "better to die on your feet then to live on your knees"

[keninmorganhill]

Armond...

No big secret here but an old mechanics trick. If you have some used brake fluid sitting around... "even some new for that matter"... poor a fair amount down each cylinder and let it sit overnight. It should free up just about anything stuck and / or rusted together.

Once they've sat overnight, if you can.. tap the pistons with the hammer handle from the top and bottom. "Lightly" is the key word here.

I use this method with frozen brake caliper pistons all the time and it's not failed me once. Have done many times over with engine pistons as well.

Good Luck,

Ken

[Armond]

I appreciate the recommendations. Thanks so much to all.

[ricortes]

A trick taught to me by a vintage outboard motor collector is to fill the cylinder with water and use a grease gun to pump up the pressure. You would have to bolt a head or a plate on of course. I converted a spark plug by knocking out the insulator and brazing in a zerk fitting. I haven't used it on a car yet but I have used it on 60 year old outboard motors and 40 year old motorcycles with great success.

Rick

[TobyB]

I'm a hopeful bastard. My hope would be that the pistons are really not

in very bad shape. I know, it's a long shot... but they're the only

really valuable part in an old 2002 motor!

So to that end, I'd pull the crank. Then I'd try all the tricks above, including

Coke (with phosphates in it to remove rust)

and try to get the bores clean. If'n that didn't work, I'd try to move each

piston down in the bore, being careful not to bang the skirt into anything.

Then I'd mechanically remove the rust with a hone with old stones on it,

and remove the pistons one at a time. If they'll come out.

At this point, putting the crank back in to use to move the piston sometimes helps.

But getting the pistons isolated by removing the crank's a real help-

often 2 or 3 aren't really stuck, it's the one that had the intake open that

was the real problem case... then once the others are out, you can put the

crank back in to get the problem case out.

t