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  1. #1

    2005 XLT 1200 compression test HELP!

    Bought ski with engine seized. Don't know if it ever had a compression check. I removed exhaust last week thinking I likely have to remove head to find broken "stuff" Since its 50 here in NY today I thought I would borrow a compression tester and check each cylinder.

    Question--can I turn over ski with entire exhaust removed to check compression? I understand I should keep spark plugs removed from motor but connected to plug wires but have plugs lay on engine to protect electronics? I did notice a "high temp" alarm when I connected battery and turned ski over for the first time. I assume alarm is from exhaust being removed?

    Any additional tips on this compression test are greatly appreciated!!
    Thanks!!


  2. #2
    Dave in DE's Avatar
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    yes, you can check compression with the exhaust removed without issue. more then likely your correct on the temp alarm as well.

    as for additional tips: wire the throttle full open and make sure the choke is open as well. then do your test. I usually connect my jump starter box to the battery to keep battery up and make the test more equal for all cyl's. but just make sure your battery is fully charged. compression should be about 125/130ish.

  3. #3
    WaterDR's Avatar
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    Mine ran for years with compression under 110 and always started.

    if the motor is seized though, why check it?

  4. #4
    Folks,
    Thanks for the responses! I know motor was seized when given to me. I wanted to see to what extent. Ran a compression test but forgot to keep throttle wide open. 50-50-0!!!!. rear cylinder dead. Friend I borrowed compression tester said its not reliable but you can get an idea. I'm questioning the 50. Since first 2 cylinders were exactly the same and 3rd was zero, I knew where to focus my attention on. Well rear piston melted. See pic. Other (2) cylinders were perfect. Used a magnet to go into rear cylinder for metal--nothing. Should I take apart next (2) cylinders, to go into crankcase with magnet? Any advice is greatly appreciated! Thanks
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  5. #5
    Dave in DE's Avatar
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    Wow, that cyl sure is smoked. But so long as the case doesn't have any holes in the lower end it's rebuildable. Or get a rebuilt one from pwcengines or one of the other builders. Probably 12/15 hundred for a rebuilt motor

  6. #6
    WaterDR's Avatar
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    That motor is a boat anchor unfortunately. Heard a lot of bad luck with 1200 rebuilds. Those 1200 motors are not very good.

  7. #7
    The other cylinders look perfect. I'm going to remove the engine, take the other jugs off and turn motor upside down, drain/flush out, and see what I can see. What should I use to flush crankcase with? Anyone have local NY re builders? Anyone know places for crate engines? I'm thinking of removing oil injection and going with premix. Add a Dplate and at very least clean the carbs depending on what I see. Thanks again for the feedback, expensive decisions ahead!

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    Dave in DE's Avatar
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    That motors going to need a total disassembly, cleaning, and rebuilt from ground up. not just a flush and repair. To much has gone through the crank bearings to survive.

  9. #9
    Understood--I'm in contact with local engine re builder. Going to remove engine hopefully this weekend.
    Question-carbs off first or no--can remove engine with carbs on? Anything else beside oil injection pump need removal before engine pull? Exhaust , air box removed already. I assume shaft coupler just disengages?? Any engine removal hints are greatly appreciated!

  10. #10
    Dave in DE's Avatar
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    Sorry fat fingered last post before I finished.
    Yes I believe the 1200 can be removed carbs attached, but to more you can remove the easier it is to lift. They are a tight fit.
    The pump and line need to come off.
    You'll either have to remove stater from the front of the motor or the wires from the electric box.
    Yes slide motor forward to disconnect coupler. When you take motor mount loose keep your shims separated for each mount to keep coupler alignment correct when putting back together. I put a nut on mount bolt and put back in mount hole with shims under it and snug to keep track of them.
    When you do the carbs do the return pressure balance from the "how to's" on this site. (8th from top)
    As far as eliminating oil pump system. Personally I'd leave it. They really are a bullet proof system. Just need to replace the lines every 2 or 3 years and secure them well. Also easier fill ups, as no oil to carry along. Less oil used as they are a variable feed system. 200/1 at idle and around 50/1 at full throttle.
    Last edited by Dave in DE; 01-24-2018 at 07:40 PM.

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