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unsticking an engine

Discussion in 'Early CJ5 and CJ6 Tech' started by all4jpn, Oct 11, 2010.

  1. all4jpn

    all4jpn Member

    so i was bored today after i got all my chores done....did my once a month check on the fhead in the cj5 future project...since i got it several months ago..its been sitting in a bath....
    i drained the oil in it a while ago...
    i immediately filled the cylinders with a mix of atf and acetone....
    (after i cleaned it,the jeep arrived headless and the cylinders were filled with mouse poo/pee)
    still its stuck..the level of fluid hasnt gone down/seeped...
    today i tried a lil heat..
    [​IMG]
    still nothing..........but its a cool pic....i figure at least try to save the rotating assembly...what else to try..?(while its still in the jeep)
     
  2. napaguy

    napaguy Banned

    Usually with these time is your friend...but unfortunately I have done everything possible and still had them stuck. If its a long term project it cant hurt anything to keep it soaking
     
  3. Pilly's Willy

    Pilly's Willy New Member

    I have heard of ol mechanics unsticking old John Deere two stroke gas tractor engines by soaking them with just plain diesel.
     
  4. LarryD

    LarryD Member

    I just went through this with a 360, fortunately only 1 cylinder was stuck. After a weekend of soaking with penetrating oil and no progress, I went with a pipe and sledge from the bottom. Yours is still in the vehicle so that wouldn't work, I would keep an eye out for another block unless there is something special about that particular engine. I just had my 360 sleeved and it ran $75 per cylinder.
     
  5. all4jpn

    all4jpn Member

    yeah i figure the engine is toast..i dont know why they took the head off...i had a breaker bar on the crank nut and my 180lbs was bouncing on it...after the fire of course....
     
  6. LarryD

    LarryD Member

    They probally can be got out by some means but I am guessing if they are stuck that badly the bore wouldn"t clean up at even 60 over. I put an chisel on my air hammer and gave it a quick burst, looks like the piston would break apart pretty quick with an air
    hammer and chisel. When my flat head locked up it was the valves that were stuck, water went down the carb and rusted the valves and froze them to the guides. I couldn't turn it with a breaker bar and cheater either.
     
  7. wheelie

    wheelie beeg dummy 2024 Sponsor 2023 Sponsor

    Mouse pee is very corrosive. Try taking a thick wooden dowel rod and good hammer, like 3 or 5 pounder, and smacking the tops of the pistons one at a time. Only thing is you may break some rings. Start gently sorta and hit progressively harder. Maybe a few swats every day. Just a thought.
     
  8. jglad

    jglad Village Idiot

    I have had only limited success with soaking an engine to free it up. I have tried just about all the formulas people have mixed up to try to free them. I found the best way is to remove the crankshaft first and then use a block of wood and a big hammer to knock the pistons loose one at a time. The pistons will come out through the bottom of an F Head which is the direction I pounded them the last stuck one that I took apart. I wound up cracking a couple pistons but the block needed bored anyway.
     
  9. 1960willyscj5

    1960willyscj5 Well-Known Member

    if the rest of the block is good and you are going to reuse it, put a block of wood just slightly smaller than the pistons on top of one and then smack it with a 5lb sledge a couple of time. Then the next, and the next.

    A couple of times a day unless you are in a hurry. Then just pull it and drop in a Pinto engine. Unless you particularly want the f-head in there.:stout:
     
  10. hopp

    hopp On our way....

    I'd try electrolytic rust removal. Fill the cylinders with a solution consisting of 1Tbsp "Washing soda"(Not baking soda) to 1 gallon water. Hook a battery charger - lead to the engine block and + lead to bolts suspended in the cylinders. Then run 1-2A ~12Vthrough it for several days. Should make lots of Hydrogen and Oxygen and should unstick the parts without damaging the good metal. See here:
    http://www.oldengine.org/members/orrin/rustdemo.htm

    Just did that to de-rust my frame and it came out great!
     
  11. DREDnot

    DREDnot Not new to JEEPS

    :iagree:

    That is a neat trick.
    My great uncle used that method on old radial engines he found to rebuild for stearman bi-planes.
     
  12. kaiser_willys

    kaiser_willys Well-Known Member

    the last one i unstuck I took a pick and cleaned around the top of the piston @ the cylinder wall, pb blaster a short 2x4 and a hammer did the trick. scratch that the last two i did that way with good results, even got one to run and could have gotten the other to run if the owner would have come up with some $ for a head gasket:rofl:
     
  13. MA74CJ5

    MA74CJ5 Member

    Marvel Mystery oil I hear works.
     
  14. Steve's 70-5

    Steve's 70-5 Active Member

    I heard brake fluid will do it
     
  15. Howard Eisenhauer

    Howard Eisenhauer Administrator Staff Member

  16. Yankeefist

    Yankeefist Sponsor

    I have used a tractor hydraulics system to unstick a few motors.
    First, you need a head on the motor, then hollew out a spak plug and weld a fitting to it so you can hook the tractors hydraulic line to it. Then place it on one of the cylinders that has the piston towards the top. Then simply apply pressure using the tractors hydraulic system. Works every time but probably not practical for you if you don't own a tractor.
     
  17. lhyatt

    lhyatt Member

    I would soak w/ "Aerokroil"???(spelling) or "Knock em lose".I've had great results with both.Not to sure 'bout "Sea Foam"..I then would hook the battery up backwards,and bump a few times a day.Eventually drive it down the road.
    Good luck
     
  18. Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Don't know what hooking the battery up backwards has to do with it because the starter will still run the same direction no matter the polarity.
     
  19. Mike S

    Mike S Sponsor

    The hydraulic/tractor thing is a good idea, but it could also be done with air pressure.

    To get the most force, use the piston that is closest to half way between top and bottom----this will put the crank as close to 90* as possible, and thus most moment arm to turn the crank.

    You could even switch between the two pistons whose crank throws are 180* apart, this will apply a "Rocking" force to the crank, kinda like when you "rock" the Jeep to get it out of the hole you got it into.
     
  20. Rralphs

    Rralphs Old Member

    I had a John Deere G I unstuck by pouring brake fluid into the cylinders and hooking an air compressor to the spark plug hole. I bought a fitting that is used to pressurize the cylinder and hold the valves shut. Anyway I left it on one cylinder for a day then the other. When I came back the crank had moved. Its one thing to pour stuff in but the pressure gets it down where its stuck at.