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FH680V sucked up choke flap screws!

Discussion in 'Mechanic and Repair' started by captken, Dec 13, 2012.

  1. captken

    captken LawnSite Bronze Member
    Messages: 1,704

    I was running at top rpms. The engine changed pitch, I was listening, wondering, then she took off running mega rpms, throttle unresponsive, kill switch quick.

    Engine shut down. Choke shaft sticking out...hmmm wtf?
    Slipped shaft into carb, attempt restart.
    Turned air filter wrong side in to choke engine. Engine starts, misfiring all over the place.
    Disasemble air snorkle. Remove carb. Choke flap screws gone.
    They are little,
    They are brass. At my shop now, old carb for missing screws, will repair in the morning.

    Question: Will brass melt quickly in combustion chamber? If it still runs probably no damage?
    What do you think? Put her back together and run her?
    Has this happened to you? Permatex the screws?
    Kawasaki sample engine on Exmark,the FH770D is down, blown head gasket, need to use the Hustler FH680V mower tomorrow or no steaks for dinner!

  2. captken

    captken LawnSite Bronze Member
    Messages: 1,704

    Can this engine ingest a couple of small brass screws and survive?
    Should I have to tear it down or just run it.
  3. piston slapper

    piston slapper LawnSite Platinum Member
    Messages: 4,335

    Fix the carb..The engine should be Ok...
    They can eat alot more than that and run just fine,,,
  4. captken

    captken LawnSite Bronze Member
    Messages: 1,704

    Thanks, thats what I thought, glad for your vote of confidence.
    Waiting on a head gasket for the other engine you helped me with.
  5. BigFish

    BigFish LawnSite Platinum Member
    Messages: 4,151

    If it was me, I'd pull the heads, at the very least pull the valve covers and plugs. Check and make sure they didn't bang up the plug/s crack the insulator nose, etc. It ain't gonna live long with ceramic bits rattling around in the jugs.
    You also wanna check the rocker arms/pushrods, make sure they're still in place and nothins bent, but hey...........its your motor.
  6. ed2hess

    ed2hess LawnSite Fanatic
    Messages: 14,442

    Pull the heads and find the darn screws. I had one on top of the piston and it sounded like the end for the engine. No it didn't melt.
  7. BigFish

    BigFish LawnSite Platinum Member
    Messages: 4,151

    ".........you got to ask yourself one question: " Do I feel lucky?" Well, do ya punk?"
  8. piston slapper

    piston slapper LawnSite Platinum Member
    Messages: 4,335

    Don't listen to those guys...:waving:....listen to your engine....
    Fix the carb and run it...then you'll know if you need to look inside...
    Chances are that it didn't ingest both screws at the same time...and they are small and soft..
    They are probably in your muffler...
  9. captken

    captken LawnSite Bronze Member
    Messages: 1,704

    Engine did start, but ran only on one cylinder, and very poorly.
    Took the spark plug out of dead cylinder, apparently the screw hammering around in the cylinder or something caused the thing you bend to gap the plug to close up and contact the electrode tip.
    Got a screw driver to pry it back open and re gapped it.

    Started the engine up on the one good cylinder, with the spark plug out of the other cylinder and advanced the throttle all the way, can't say for sure, but I thought I saw something fly out of the cylinder that had the plug removed.
    Mechanical loogie? Spittin' out the bad? I don't know, but after I installed the plug, she ran fine all day long.

    So that's the story.

    The end.
  10. ricky86

    ricky86 LawnSite Silver Member
    Messages: 2,122

    Leave it alone, and that screw will be lodged between the piston and cylinder wall. Take it apart, and it will have harmlessly passed through and is sitting in the muffler.
    Well, you feeling lucky. Times like that, it's nice to have a bore scope. Might be a good idea to check the throttle shaft for excessive wear too.

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