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fc420v possible smoked cam

Discussion in 'Mechanic and Repair' started by mngreenguy, Aug 10, 2011.

  1. mngreenguy

    mngreenguy LawnSite Member
    from mn
    Posts: 88

    I recently dissembled and honed and re-rung the piston. I checked all the clearances per the service manual. Everything checked out, so i assembled all the pieces and she started right away ran perfect for about 30 seconds then a loud squeaking noise started so i shut it down.

    So i'm back to tearing it down, there are aluminum shavings on the crank case walls by the cam shaft. I can turn the cam by hand but it won't come out and i don't want to break the case by prying.

    You guys have any tricks? A small slide hammer would be awesome but i don't have one.

    Thank for your help over the years.
     
  2. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,024

    Did you loosen the rocker arms and remove the pushrods then push the tappets away from the cam lobes ?
     
  3. mngreenguy

    mngreenguy LawnSite Member
    from mn
    Posts: 88

    yep sure did ill post a pic when I get home
     
  4. topsites

    topsites LawnSite Fanatic
    Posts: 21,654

    This is a tough cookie, for sure, with rebuilds it almost always is.

    Whatever you did metal shavings is a bad sign and worse to come if you can't get it all worked out,
    not saying it's your fault but rebuilding engines is like taking a shot in the dark, although in this case
    you know where the target is but there's still that fine chance you'll miss because how do you know,
    just based on where those metal shavings were, that it's really the camshaft.

    How do you really know, how can you be absolutely certain, the answer is you can't.

    This is as much if not more for other readers having considered or considering a rebuild in the future.

    I can't say, nor am I saying that it's your fault, but by the time you invest in a camshaft and do everything
    again, how do you know it's not going to turn into yet more parts breaking down that need replacing?

    This is the reason why once it gets to where an engine needs rebuilding, in ways just as well off replacing it...
    You just never know, after you have done all of the work according to specifications, whether or not
    that POS is going to run the way it's supposed to.

    Good luck with that.
     
  5. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    If the cam is hung in the block...the block is junk.
    The cam bushing is machined into the block...or at least it was...

    Probably the result of an obstruction in the oil passages..stick a fork in it...its done.
     
  6. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    I grabbed a 420 block off the shelf and did some checking...
    Its possible that you left out the relief valve ball and spring, or it is stuck.
    Its located next to the oil pump and below the gov gear.

    I would go ahead and disassemble the pump...just out of curiousity..

    IMG_0166.JPG

    IMG_0167.JPG
     
  7. mngreenguy

    mngreenguy LawnSite Member
    from mn
    Posts: 88

    that's what I expected but any advice on getting the cam out without damaging anything else?
     
  8. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    Use 2 large screwdrivers or prybars....
    I doubt there is much you're gonna be able to salvage...
    Take a little of your frustration out on it, and get it out.
    Wear gloves and safety glasses.
     
  9. mngreenguy

    mngreenguy LawnSite Member
    from mn
    Posts: 88

    so if the block is done what's my best option?
     
  10. Sharpcut 1

    Sharpcut 1 LawnSite Senior Member
    Posts: 450

    If you need a cam, and you can't find one in a dealers' stock, a little heads up. Kawasaki is waiting on them from overseas, but with the earthquake they claim they won't be in the states until the end of September. Good luck.

    Engine I'm working on wiped out the ACR on the cam, it would rip your arm off and break recoils!!!
     

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