Unseizing a piston

[Rusty Chrome (Malcolm Parker)]

Another way might be to leave it in a room with an unattended small child or dog and tell them before you leave the room that under no circumstances are they to touch it.

[Bob Purton]

The barrel is not attached to the engine block so I can twist it, whack it, leave in the care of a small child or dog etc etc. I took my Fiat in for its MOT yesterday [Grande Punto, the one Ann Robinson says cannot be steered by the worlds strongest man!] I run my seizure prob past the examiner, he suggested a rust eater like Jenolite so its soaking it the stuff as we speak. I have used it before for dissolving rust but had forgotten about the stuff. I will let you know what happens.

[Jonathan Poll]

[quote auth Rusty Chrome link=topic=3265.msg22077#msg22077 date=1335564439]
Another way might be to leave it in a room with an unattended small child or dog and tell them before you leave the room that under no circumstances are they to touch it.
[/quote]

  Good one!

[Bob Purton]

Hurrah!!   I got the piston out this afternoon.  Jenolite appears to have broken the seal. The bore will have to be bored out to the next size as its pitted, not surprising realty.

[marcus]

Great result!

[Rusty Chrome (Malcolm Parker)]

Excellent, have to get some of that.

[Big Al]

Hurrah!!   I got the piston out this afternoon.  Jenolite appears to have broken the seal. The bore will have to be bored out to the next size as its pitted, not surprising realty.

There is Jenolite at the end of the tunnel.

[Bob Purton]

Oh very good Al!  I have noticed each time I have removed a long time seized piston that the rings get a build up of crud behind them forcing them out against the bore, I guess if a rust eater can penitrate the ring gap and disolve this crud thats how it allows it to free up.

[Big Al]

Oh very good Al!  I have noticed each time I have removed a long time seized piston that the rings get a build up of crud behind them forcing them out against the bore, I guess if a rust eater can penitrate the ring gap and disolve this crud thats how it allows it to free up.

I concur but blamed rust. Maybe not but what ever it is it is a damned nuisance.

[Bob Purton]

I've always found it to be a white powdery substance under the rings but I guess it depends on if the rings are in alloy grooves or steel grooves.

[Big Al]

I've always found it to be a white powdery substance under the rings but I guess it depends on if the rings are in alloy grooves or steel grooves.

Sounds more like Ali corrosion but I cannot say I have found ali ring grooves showing signs of corrosion other than when it was obvious and the piston damaged or dead already. Might have to get a magnifying glass out on a few stashed suspects awaiting possible re use that have stuck rings.