Stuck Cylinders/pistons

[dweymer]

OK, I've got this alu engine from a 67, it is siezed. I am trying to save the crank, case, and rods. The pistons seem to have rusted to the cylinders, and I could only remove one. Any ideas on how to remove the others? I cannot rotate the crank at all. I have soaked the tops of the pistons (3 at a time) in PB blaster, pounded with a rubber mallet etc. I do not want to damage the case, but I am running out of ideas.

[Henry Schmidt]

We have encountered this several times before and the only thing we could do was split the cylinder. You can use a die grinder w/ a cut off wheel and a large chisel. Once the cylinder is split it will generally come right off.
Good luck.

[dweymer]

That's what I figured I would have to do. Thanks Henry. I will talk to you soon about pistons/cylinders.

[Rob 930]

I had this happen once too. I used a 4 1/2 in. angle grinder to cut open the cylinder. I made a couple of cuts along the axis of the cylinder, one on the top and one on the bottom. I was then able to split the cylinder the rest of the way and remove it in two pieces. I'm sure a die grinder would work too, but it would likely take a lot longer than a small grinder.

Ouch. It's painful to use such drastic methods, but you risk hurting the parts you really want to preserve if you use too much force.

[dweymer]

yes this s*cks. I've got two off without cutting, since both kids are sick garage time has been far between.

Thanks for the help guys.

[trak ratt]

I used a large pipe; placed on top of piston, strike the top repeatedly with 5lb persuader. Soak pistons with penetrating oil first. Had an idea about recycling the iron cylinders.

[dweymer]

I do not want to risk damage to the rods, crank, or mains by that kind of force, but I thought about it.