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  1. #1

    Key Snapped On Crank?

    As some of you may recall, i though my bendix broke when the ski wouldnt crank over anymore and the starter was turning. Well, I Took the flywheel cover off, and saw the clutch fully engaged... Hit the starter and guess what, the flywheel turned over!

    Well now, you might be thinking this is good? Well, the problem here is the flywheel turns, and the crank does not. The bolt is tight, so its not like the flywheel came off, it would appear the key on the crank snapped... This sounds bad, very bad...

    What do i do about this one?

    I didnt pull the flywheel yet, since i need to rent the tool again, and im done with the ski for today.


  2. #2
    Race, wreck, repeat delagem's Avatar
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    I've heard of sheared keys before, sounds like that's what you've got. You can just buy a $9 steering wheel puller at Auto Zone, and get some better bolts.

  3. #3
    Yes, im aware the key is sheared, and i can get the flywheel off. My question is how do i fix it? Can i get the stock key out, or would i need to cut a grove in the crank and put a key in. I probably need to pull the engine again?

  4. #4
    100 MILES OF HEAVEN AND I AM SMACK IN THE MIDDLE KEYZBUM's Avatar
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    Wait a min...
    you are saying that the bolt is tight..???
    you mean when the flywheel rotates the nut stays still ?? or does it spin as well?

  5. #5
    Click avatar for tech links/info, donation request K447's Avatar
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    Make sure there isn't something preventing the crank shaft from rotating.

    Sounds like something might have jammed (pistons, bearings, or even the impeller), and the flywheel then sheared the key off.

    With the Bendix NOT engaged, can you turn the engine over by hand using the PTO coupler?

  6. #6
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Ironically enough, this just happened to me today..

    If you haven't reremoved the flywheel how do you know the key is sheared?

    Get the flywheel off first. It may have slipped out of the groove.

    DO NOT cut another groove for the key. You'll never hit the timing correctly. Just drive out the remainder of the old key if it did shear.

  7. #7
    I will pull the flywheel tomorrow.

    The flywheel turns and the bolt stays still. It looks like its all the way on, and the crank turns just fine by hand.

    Probably record a video for everyone to watch in amazement. Im having some obscure things break recently...

  8. #8
    2000 pro 785 (son's) 1998 pro 785 (dads) old guy in mich's Avatar
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    if its spun/sheared the key make sure you clean the keyway very well especially the edges, also ck the flywheel, it may be oversized now (hole as well as keyway). if the keyway is trashed you maybe able to go to the next size key, but that would entail broach milling both the crank and flywheel to that size, dificult because you should maintain original position. other option is new/used parts. if original parts dont fit up snug, and you have to replace something start with just the flywheel. its much softer so a new one may tighten things up enough to work.
    sorry best i have to offer, good luck.
    maybe someone has an better/easier fix.
    Last edited by old guy in mich; 07-28-2008 at 04:43 AM. Reason: addition

  9. #9
    Watcon's Avatar
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    Flywheel falling off.

    If your flywheel key shears, that means you didn't torque your flywheel bolt correctly or the taper is galled or damaged.. The key "locates" to flywheel for timing alignment only and offers no strength to keep the flywheel in position.. I have installed a flywheel many times with no key.. It's the taper that locks the flywheel to the crankshaft, so it must fit perfect..

    Randy

  10. #10
    Quote Originally Posted by Watcon View Post
    If your flywheel key shears, that means you didn't torque your flywheel bolt correctly or the taper is galled or damaged.. The key "locates" to flywheel for timing alignment only and offers no strength to keep the flywheel in position.. I have installed a flywheel many times with no key.. It's the taper that locks the flywheel to the crankshaft, so it must fit perfect..

    Randy
    Whats the torque spec on the flywheel bolt? I tightened it, but i was assuming the key would be able to handle the torque from the starter and the bolt is there to stop it from falling off. From how difficult it was to remove the first time, i guess that makes sense. It just is odd to me how it broke at a random time, I was cranking for about 1 second and it started to rev a little and died about a second later. A few seconds after it died i went to the starter to turn it over again and it cranked probably once or twice and just started freewheeling.

    And you are saying i can torque the crap out of the bolt and i wouldn't even need a key?

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