Piston Removal

I'm getting ready to try the boiling liquid method to unstick a piston. I was thinking of using brake fluid, but if there is something better, I'll give it a try. Any suggestions?
Thanks,
John Cullom
Westminster, Maryland

I have used PB Blaster to unstick pistons . And I have used applecider vinger to unstick pistons . Good Luck on your piston removal . ( David Davis in PA. )

Depends on what is stuck to what.

If is just the rings stuck to the bore, then diesel or penetrating oil usually work, but you need to shock the piston to break the seal between the two parts as the liquid rarely gets right between the two.

A piston body is a bit more of a problem, but dry ice on the piston crown and inside the body while heating the block with hot water will increase the nominal clearances for a short period, and again you will have to break the rust seal.

If the piston is cast iron and the block has to be repainted, then a decent cooking in an industrial oven at 600 degrees C for 10 hours and a slow cooling will do the job, a fire of old pallets will also work if you have enough ashes to bury the block in and enough to keep it from cooling off too quickly.

Phosphoric acid may work, but old and soft cast iron is too easily attacked by this liquid to be safe over a long period. It will remove any rusted metal and leave just soft graphite behind, have lost a few parts that way :-((

Your (US) favourite drink has Phosphoric acid in it (read the label!) and it is a bit more dilute, so buy a few cans of Coke and try it!

All these will need a hydraulic jack to push the piston along once you've broken the seal, but it can be nerve-wracking !!

Peter
Peter & Rita Forbes
email:- diesel@easynet.co.uk
Lister Cold-Starting Diesel Engines
Engine info etc at:-
http://www.oldengine.org/members/diesel

Thanks David & Peter for the suggestions. I don't know if the rings are stuck, but I suspect it's the piston itself, as it's positioned under the oiler hole. I imagine the oiler was left off & the moisture entered through the hole & seeped around the piston. The cylinder ahead of the piston is in excellent shape. I've tried the pressurized grease method, but it didn't work as I couldn't achieve a good enough seal. Good whacks with a sledge hammer on a block of wood just split the wood. I have it upended now with brake fluid sitting in it. I'll be looking for someone with a press next week. Fortunately I have a spare Galloway piston in I have to get drastic.

John you always could make your own "press", with the help of a few pieces warm rolled U-bars of 2" you make a rectangular window around the engine block and place a 6 or 8 tons hydrau- lic jack between the top U-bar and the piston. For safety place a piece of 3/8 or 1/2" steelplate on top of the piston to protect the piston's bottom. Fill it with your favorite fluid and give some pres- sure from time to time. It depends in time, but it comes at a moment you didn't already expect it.

I once had the same situation, while working in the shed, I heard a "crack" behind me and thought #$@#, looking to the setup and give some more pressure with the jack and there she goes free as a bird in the sky. Called my wife by intercome to bring a copple cold ones to the shed and had a little celebration :o))

See ya,
John H.

John ,sounds like we are at the same stage . We have had our Trusty engine cylinder immersed in our favourite de rusting bath ,molasses .It was there for about a month it was then pressure washed with water and immediately put into a tank of diesel . The piston is at the bottom of the stroke so it has not got far to go . We will use a screw to press it out early next week ,got to be positive about these things !

We pushed a piston out of a Tangy engine the other week ,it took 30 tons on the press to get it to move from then on about 10 tons each time it moved. When it came out one of the rings had sheared but miraculously had not damaged the bore
Good luck with yours.
Peter and Jo Ogborne
Trigg Western Australia
jopetertrigg@optusnet.com.au

If you get that fluid good and hot, it will seep on down and break everything loose.

Tim from the Big Brown Bus told me about this trick, but he said to put a wick from a lantern or lamp in the fluid and light it.

He said that this has worked every time to get suck pistons out of the cylinders with little or no fuss.

hope this helps.

William J. Pfeiffer Jr. &
Sharon A. Cook
Prospect Heights, Illinois
rusty-iron@home.com
http://members.home.net/sacook15/index.htm