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  1. #1
    thesepaperwings's Avatar
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    Lost compression on front jug!!!

    Was riding fine, about 3 hours into the day it just coughed for about 4 seconds and then died. Wouldn't crank over, checked for water in the hull and there was just a little bit, nothing to worry about. I tore it apart today and found rust on my #1 plug and no compression. I looked in and didn't see any shavings or a hole. Who wants to guess what happened???

    My first guess is that I blew an O-ring and flooded my chamber, who thinks different?


  2. #2
    axgrider73's Avatar
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    Your probably right but rust doesn't happed in three hours. I wonder how long it has been leaking?

  3. #3
    What does the cylinder walls look like? Leaking pipe to manifold on your exhaust will leak water into #1 cylinder. Look inside you manifold and see if you have what looks like a "clean" area. Of course that doesn't explain the "zero" compression unless it washed the oil off the walls.

  4. #4
    I have seen rust on the nut portion of plugs many times. It's from condensation due to temp changes inside the engine compartment. I know the Kawi's seem to sweat massively from past experience. I am assuming the rust is on the outside of the plug because you didn't mention where exactly you found it.

    It's always best to pull off the seat or engine cover and leave it off when storing so the engine compartement can breathe. It will also save you from rusting up the crank bearings when the engine can match the air temp as it's changing and not after the temp differences finally sink into the hull.

    As for the compression loss...what kind of condition is the head gasket in? Do you see any areas where there is black soot anywhere on the gasket surface of the cylinder? It will show up fairly easily if the head gasket was leaking. The cylinder surface will look pretty well clean and shiny accept for where there would be compression blow-by which leaves carbon deposits from combustion. Can you post pics?

  5. #5
    thesepaperwings's Avatar
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    I don't have head gaskets. I have a one piece ADA head with o-rings. The rust was on the end of the plug where there should never be rust. The outside of my plugs always end up with rust because of the condesation, that is no big deal.
    I found something else today. When cranked it was only spinning about have speed but my battery was low so I figured that wasn't a problem. Fresh charge on the battery and the ski still only "lumps" over when cranking. It is faster with the plugs out but still not as fast as it should be.

  6. #6
    Ahh then it sounds like you did get some water inside and it has sat for a length of time. Diagnosis is pretty tough to do when a person can't see what things look like

  7. #7
    btldigger's Avatar
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    I would say you scored a piston. Pulling the cylinder will tell the whole story.

  8. #8
    thesepaperwings's Avatar
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    Quote Originally Posted by btldigger View Post
    I would say you scored a piston. Pulling the cylinder will tell the whole story.
    That's what I'm thinking. Due to work and school it might be a week before I even get to tear into it. God this sucks.

  9. #9
    thesepaperwings's Avatar
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    Well here it is. Lots of grey dust so that sucks a big one. There is a notch in the dome where the ring tore and the jug itself has a low spot now. That about does it for my riding this year.
    Questions:

    What do I need to order?
    Can the dome be fixed? (other then that it is perfect)
    I felt for damage on the wall and so far i think it could be saved, what do you think?
    What do I do about the low spot?Can you deck the top and even it?
    How much does this suck on a scale of 1 to 60000?
    Do you think it would make a pretty bonfire?
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  10. #10
    thesepaperwings's Avatar
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    I would also like to say that I forgot what a PITA taking off that head is!

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