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piston will NOT move... now what?

Discussion in 'The Hokey Ass Message Board' started by chopo, Aug 1, 2009.

  1. This works, I've done it many times, only I used crankcase drainings and left the end of the grease gun off to make filling it easyer.
  2. It take a BIG hammer and a LOT of swinging to equal the force of a one ton press.

    The grease turns your piston and cylinder into a hydraulic cylinder. A 3.5" diameter bore has an area of 9.62 square inches. Apply 1000 psi from a grease gun and you have 9,620 lbs pressing the piston out. some grease guns claim 10,000 psi, which would be 96,200 lbs of force, or almost 50 tons.

    Some times a the shock of a steel hammer moves the metal better in a small area, like when stamping numbers, don't be mislead by that, a press is way more powerful than a hammer. <!-- / message --><!-- sig -->

    This is the way to do it
  3. Kroil arisol is what I use on stuck parts and a soft blow hammer. Spray and let set for an hour, remove rod cap and rotate the crank for some clearance then carefully tap on the piston until it breaks free.
  4. chopo
    Joined: Feb 20, 2006
    Posts: 1,265


    ok got it. now are we talking hand pump or air operated grease gun?
  5. Try some CLR. Worked on a lawn mower for me.
  6. cinemafx
    Joined: Mar 28, 2009
    Posts: 94

    from Vancouver

    Hand pump works just fine. I pushed two pistons out of a bore that had rust growing like trees off the wall. Pistons came out untouched.
  7. attastude
    Joined: Nov 30, 2008
    Posts: 235


    you could bolt on a steel plate with a threaded hole,install a bolt, protect the piston, thread the bolt down and put some pressure on it, lube the piston with penetrant. leave the tension on overnight.
  8. carcrazyjohn
    Joined: Apr 16, 2008
    Posts: 4,844

    from trevose pa

    Use the grease method
  9. btmatt
    Joined: Nov 15, 2006
    Posts: 227


    How about ATF and Acetone, 1:1? Stuff creeps like crazy.
  10. 40ford57chev
    Joined: Sep 6, 2007
    Posts: 72


    I did the
    " fill it full of vinegar"
    trick. On a 1st Gen Hemi.

    It took a long time and I still had to drive one piston out with
    allot of force. I did not salvage any pistons this way.

    I have mixed feelings about the vinegar process.

    1. it worked for me.
    2. A warning about vinegar...

    Vinegar is a mild acid and with dissimilar metals you need to be aware of Electrolysis...

    After I got the pistons out of the block I didn't have time to clean up the
    Pistons, wrist pins and rods. So I just dumped them into a plastic container full of fresh vinegar so they wouldn't dry out and forgot about them for a month.

    About a month later i went back to clean up the pistons, rods and wrists pins.

    The wrists pins were about half gone, eat up from Electrolyses.
    Pistons were discolored but not OK and the rods had
    a dark gray coating on them I had to clean off by blasting with
    a bead cabinet. Block wasn't hurt, actually looked very good, but
    it didn't have a extra 30 days soaking on it.
    Rods and pins reminded me of a plating process. Metal from the
    wrist pins on the rods was my impression.

    Alt method but I didn't try it:
    The guy that told me about vinegar also said heating up the piston
    with a torch to melt wax and allow the wax to run down between the piston and cly wall. But piston must be kept warm enough to give
    the wax time to work. I've never tried this but I know it works on
    corrosive plugs and bolts. He said be very careful with the torch.
  11. rc.grimes
    Joined: Aug 14, 2007
    Posts: 698

    from Edmond, OK

    Hand pump grease gun works well. I've done it so often I upgraded to a pneumatic grease gun. They make some interesting sounds when they finally break loose but I have yet(in 20 years of doing it this way) to have one break from the removal.
  12. GlenC
    Joined: Mar 21, 2007
    Posts: 757


    I had a vintage motorcycle steel barrel with an aluminium piston well and truly siezed in the bore, so I dumped it in a tub of caustic soda until the piston dissolved enough to get it out without damaging the bore liner. Detsroyed the piston of course, but saved the barrel, even cleaned the old burnt on grease and crud off the fins.

    Caustic soda is nasty stuff, be VERY careful if you use it.

    Cheers, Glen.
  13. B.A.KING
    Joined: Apr 6, 2005
    Posts: 3,748


    use the grease method,you can move the world with hydraulics!!! and let us know what worked.inquiring minds want to know:p
  14. chopo
    Joined: Feb 20, 2006
    Posts: 1,265


    gonna do the grease. now is 1/8 plate steel heavy enough? or should I get a piece of 1/4 plate? And should I use a king ping size grease fitting. thanks for all the help.
  15. The Coke as rust remover is definately a wives tale. I've done my own tests with rusty bolts in Coke and after even a week or two the rust is absolutely undisturbed. Ya got a better chance of dissolving rust with chocolate milk (LOL) than Coke. Maybe some older formula of Coke used to work but that ship has sailed.
  16. sawzall
    Joined: Jul 15, 2002
    Posts: 4,729


    dude.. try what you have.. the worst that will happen is the grease will squeeze out.. what engine is this anyhow??
  17. This works killer.

    Had a buddy's Flathead with the piston stuck rock solid/rusted in the bore,and I mean STUCK HARD. Soaked it in WD40 - pounded it with the sledge - no dice.

    Upon Flatoz's recommendation, we added an ATF/Acetone combo and poured it into the bore. Left it over nite, the next day the pistons just came out REAL EASY.

    Amazing stuff.

    PM Flatoz if you wanna try this - he'll give ya the scoop.

  18. chopo
    Joined: Feb 20, 2006
    Posts: 1,265


    230 flat 6
  19. B.A.KING
    Joined: Apr 6, 2005
    Posts: 3,748


    the accetone/atf does work also.50/50 mix. also worth a shot. i know make up my mind.try thr 50/50 mix first,then the grease.
  20. cinemafx
    Joined: Mar 28, 2009
    Posts: 94

    from Vancouver

    You want the plate to hold it's shape. Plate will deflect in the middle under pressure because it is flat and not hemispherical. You do not want to put lany lateral strain on bolts. 1/2 plate will do it. Make a good thread for grease nipple with a sharp tap. Use an old head gasket to seal. The beauty of grease is thick and shouldn't spray all over.
  21. chopo
    Joined: Feb 20, 2006
    Posts: 1,265


    ok heres the deal. I did the grease deal and it kicked ass. now the only issue is the piston was almost at tdc and it took many tubes of grease to get it all the way down. thats right it took all that force to keep moving it down the bore. so the piston gets near the bottom oh maybe 1 1/2 inches from the bottom of the stroke and it stops dead. grease will not move it anymore. now piston will not go up or down. so i think its time for another motor. anyone got a dodge flat 6?
  22. Why are you concerned about saving that piston? Take and cut it out! You are prepared to look for another engine but you won't sacrifice one piston from a block that is going to have to be re-bored anyway? You can get new pistons. I'm not trying to be an asshole but I must be missing something here. I don't like to destroy parts either if I don't have to. Get that piston out, bore the block, call Egge and get six new pistons and then put on an Edmunds manifold with dual carbs and split the exhaust manifold! Keep us posted.:confused:
  23. I have worried the crank out then drove them out before but that usually ends up being a new piston as the normally come out in pieces. I actually have a 2x2 piece of oak in the garage that works real well.

    Have you tried coca cola? The wife mixes coca cola and tranny fluid, about 75% coke. You would be surprized what you can do with a little coke.
    Joined: Mar 6, 2008
    Posts: 256


    OK Horriffic, you were only supposed to knock the piston down an inch, mudball the bore, then knock out the piton thru the top, OY
    now thsts is in the hole, still mud ball it with plenty of atf, clean it up and use the stuff for cleaning rifle barrels, next day pop it out like normal,
  25. That's what I said a week ago.:p
  26. cinemafx
    Joined: Mar 28, 2009
    Posts: 94

    from Vancouver

    Why is the piston locked. When you wipe off the grease how does the bore above piston look? Does the piston normaly go out the bottom clearing all the block casting. With the the piston free now, will it not go back up the bore? Try tapping piston back up the bore with a soft piece of wood? It should go now! The bore is scraped clean from the rings and should allow the piston to move. Clean up the top of bore so the piston will not hang up there on the way out.
  27. RichFox
    Joined: Dec 3, 2006
    Posts: 10,018


    Hit the cylinder with some oil and 50 grit sand paper. Get a ridge reamer or use a die grinder to remove the ridge. The block needs to be bored anyway. Soft board or steel bar, who cares. Your thinking of junking the block and that piston anyway. Get a big hammer and drive that think back the way it came. Out the top. Ain't no old Dodge flathead six going to beat you down. Get it out or destroy it trying.
  28. tbraginton
    Joined: Dec 5, 2007
    Posts: 288

    from Nevada

    Ive had great luck heating the block and putting dry ice on top of the piston. Get the block really hot and then drop the dry ice on the piston and hammer the shit out of it. As has already been pointed out what is the issue if you break the piston?

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