Seized Piston Rings, Best Method to Remove Piston Options

[SteveNMaine]

I recently started a rebuild on a seized 1.8. I found that moisture has seized the rings and the exhaust valve on #2 cylinder. The piston is seized near the top of the exhaust stroke.

Any suggestions to free up the piston rings? I have heated the top of the piston, used penetrating oil, tapped with a mallet, etc. So far, no joy.

[Ishley]

You may have to crack the case open… unbolt all the rods and slide the whole thing out… piston, rod and barrel. Depending where the crank sits… the rod bolts might be a tough reach. Likely it’s all toast…so from there you might just surrender and buy all new inners. If you really have to get the piston out… use a press. That’s what I’ve had to do with a motor cycle once. You might get lucky. Good luck!

[Artfrombama]

Add some penetrating oil to that cylinder, put the car in 3rd and rock the car fwd/backward.
Don't pry on the fan blades, they break easily

[SteveNMaine]

Add some penetrating oil to that cylinder, put the car in 3rd and rock the car fwd/backward.
Don't pry on the fan blades, they break easily

Engine is on an engine stand with that head removed.

[Artfrombama]

Add some penetrating oil to that cylinder, put the car in 3rd and rock the car fwd/backward.
Don't pry on the fan blades, they break easily

Engine is on an engine stand with that head removed.

OK...
Fashion a pusher to attach to the head studs and push the piston out of the cylinder. IE., like a harmonic balancer remover

[SteveNMaine]

Add some penetrating oil to that cylinder, put the car in 3rd and rock the car fwd/backward.
Don't pry on the fan blades, they break easily

Engine is on an engine stand with that head removed.

OK...
Fashion a pusher to attach to the head studs and push the piston out of the cylinder. IE., like a harmonic balancer remover

Thanks, I'll give that a try tomorrow.

[porschetub]

[quote name='SteveNMaine' date='Oct 14 2025, 12:37 PM' post='3228134']
[quote name='Artfrombama' post='3228075' date='Oct 13 2025, 02:47 PM']
[quote name='SteveNMaine' post='3228068' date='Oct 13 2025, 02:24 PM']
[quote name='Artfrombama' post='3228065' date='Oct 13 2025, 01:06 PM']
Add some penetrating oil to that cylinder, put the car in 3rd and rock the car fwd/backward.
Don't pry on the fan blades, they break easily
[/quote]
Engine is on an engine stand with that head removed.
[/quote]
OK...
Fashion a pusher to attach to the head studs and push the piston out of the cylinder. IE., like a harmonic balancer remover
[/quote]
Thanks, I'll give that a try tomorrow.
[/quote
Keep the engine vertical and put some diesel in there let it soak for a while ,after that apply heat around the barrel area were the rings would be,repeat over and over...try it cheers.

[Aayala]

I recently started a rebuild on a seized 1.8. I found that moisture has seized the rings and the exhaust valve on #2 cylinder. The piston is seized near the top of the exhaust stroke.

Any suggestions to free up the piston rings? I have heated the top of the piston, used penetrating oil, tapped with a mallet, etc. So far, no joy.

I don’t know if this is a sign or not… but literally in the process of tearing down the 1.8 engine of mine. My cylinder #1 was seized and no kidding JUST got it stuck 10 minutes ago. I took it apart entirely for a rebuild but the cylinder was stuck to the piston ring and couldn’t pull the cylinder out. I rotated the engine on the stand at 90 degrees so the pistons are facing the ceiling and poured mystery oil to the brim of the cylinder. (Like an inch of fluid because it was near the top) and waited 24 hours and still stuck. Got a brass brush and scrubbed the sides waited for a bit and then put a wrench on the crank shaft and rotated it back and fourth as to knock it loose and it FINALLY DID IT! Got that thing out. Good luck with yours!

[SteveNMaine]

[quote name='porschetub' date='Oct 13 2025, 10:25 PM' post='3228153']
[quote name='SteveNMaine' date='Oct 14 2025, 12:37 PM' post='3228134']
[quote name='Artfrombama' post='3228075' date='Oct 13 2025, 02:47 PM']
[quote name='SteveNMaine' post='3228068' date='Oct 13 2025, 02:24 PM']
[quote name='Artfrombama' post='3228065' date='Oct 13 2025, 01:06 PM']
Add some penetrating oil to that cylinder, put the car in 3rd and rock the car fwd/backward.
Don't pry on the fan blades, they break easily
[/quote]
Engine is on an engine stand with that head removed.
[/quote]
OK...
Fashion a pusher to attach to the head studs and push the piston out of the cylinder. IE., like a harmonic balancer remover
[/quote]
Thanks, I'll give that a try tomorrow.
[/quote
Keep the engine vertical and put some diesel in there let it soak for a while ,after that apply heat around the barrel area were the rings would be,repeat over and over...try it cheers.
[/quote]
I tried the heating process like you described and am going to continue with that process. Thanks.

[SteveNMaine]

I recently started a rebuild on a seized 1.8. I found that moisture has seized the rings and the exhaust valve on #2 cylinder. The piston is seized near the top of the exhaust stroke.

Any suggestions to free up the piston rings? I have heated the top of the piston, used penetrating oil, tapped with a mallet, etc. So far, no joy.

I don’t know if this is a sign or not… but literally in the process of tearing down the 1.8 engine of mine. My cylinder #1 was seized and no kidding JUST got it stuck 10 minutes ago. I took it apart entirely for a rebuild but the cylinder was stuck to the piston ring and couldn’t pull the cylinder out. I rotated the engine on the stand at 90 degrees so the pistons are facing the ceiling and poured mystery oil to the brim of the cylinder. (Like an inch of fluid because it was near the top) and waited 24 hours and still stuck. Got a brass brush and scrubbed the sides waited for a bit and then put a wrench on the crank shaft and rotated it back and fourth as to knock it loose and it FINALLY DID IT! Got that thing out. Good luck with yours!

Thanks for the input. This is my winter project, so I am going to be patient with it. I built a 2056 last winter that is now in a running car. This is a spare engine out of my "parts car".

[VaccaRabite]

Penetrating oil. Lots of it.
2x4 against the piston. And hit it with a big f*&king hammer. No, no. Harder then that. HARDER! It will break free.

[Spoke]

If the cylinder is at TDC, not sure if pressure on the piston will get it moving unless someone is trying to turn the crank at the same time. Might be time to split the case.

[bdstone914]

I recently started a rebuild on a seized 1.8. I found that moisture has seized the rings and the exhaust valve on #2 cylinder. The piston is seized near the top of the exhaust stroke.

Any suggestions to free up the piston rings? I have heated the top of the piston, used penetrating oil, tapped with a mallet, etc. So far, no joy.

I have had pistons that were so stuck i had to slice the cylinder with an angle grinder and split the cylinder with a chisel.
Chance are the piston and cylinder are trashed
I also had to use several cycles with the acetylene torch to heat to a point where the piston almost melted.