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  1. #1

    No low end power

    I recently picked up a '95 SL650STD that wasn't running. I put a new battery and top end in it and it would start but wouldn't run well at all. I cut back a plug wire and it ran a little better and would idle but wouldn't go. I pulled the carbs and found a stuck needle valve which I got free and now it will start, idle and go... a little bit.
    It will rev a little bit past idle and kind of bog. If I pull the choke a little it will rev and take off like it should. I didn't check the jets because all of the screws holding the plate in place over the jets are pretty much trashed (I will have get them out with a screw extractor if I have to dig in there). I also haven't dug down to the reeds.
    I know its running a little heavy on oil right now as I mixed in about 500ml with the gas when I put the top end in. The lever connecting the oil pump to the carbs is also a little sticky so it is injecting oil at the max rate all the time.
    Any help in getting past this, hopefully last, hurdle is greatly appreciated.


  2. #2
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
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    I would go thru the carbs fully,and also the full fuel system,lines filter,clean tank,etc. Also does it look like it has 2 fuel pumps,a big one and also alittle one,if it does throw the little one away(it's a auto fuel shutoff,that is junk). Before you run it and toast the new upper end, Get that fuel system strighten up.Otherwise your tak'in a chance of running lean and burn it down. Also do a search for putting a triple fuel pump on.

  3. #3
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Welcome to the Hulk Dan.

    You MUST maintain the fuel system before you damage your new top end. Fuel issue was most likely the cause of the failure in the first place.

    Do a search for fuel system upgrade on a 650 or 750.

  4. #4
    Thanks for help. Sounds like I've got some work to do. I'll pull the carbs and see if I can't get everything apart without destroying anything.

  5. #5
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    They're pretty easy, but do 1 at a time. That way you have a complete one to look at should you get confused.

    We're here if you need help.

  6. #6
    Does anyone know where I can find the proper jetting for running this ski at about 4700 ft in elevation (Pueblo, CO)?

  7. #7
    Lake Mead Bum & BTLS Mark starflight's Avatar
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    I just looked in the manual, and it didn't have high elev. specs for the 650.
    The 750 used the same jets, but the low and high spd adjusters were changed. On the 95 750 the high spd adjusters were to be turned in a 1/4 on each cylinder. The low spds were opened a 1/4 turn. I think the prop was changed too. I would guess the 650 would need similar adjustments. I would start by turning in the highs an 1/8th, and lows out an 1/8th of a turn. And see how it goes.
    These specs were for elevations above 5000'.
    It also has a note of warning that with these adjustments, serious damage could result from running the ski at lower elevations.

    You can find the manual here... http://www.greenhulk.net/forums/showthread.php?t=38870

    BTW. I have an STD too! Welcome to the club!

  8. #8
    While I'm at it I think I'll go ahead with the triple outlet pump. I would think that the increased pressure/flow would change the carb settings (high and low speed screws) but seem to recall seeing somewhere on here that the original carb settings are still recommended for an otherwise stock boat. Is that correct?

  9. #9
    Lake Mead Bum & BTLS Mark starflight's Avatar
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    Quote Originally Posted by DanHall View Post
    While I'm at it I think I'll go ahead with the triple outlet pump. I would think that the increased pressure/flow would change the carb settings (high and low speed screws) but seem to recall seeing somewhere on here that the original carb settings are still recommended for an otherwise stock boat. Is that correct?
    You shouldn't need to change settings with the triple pump. The float valve regulates whats needed for the carbs, and the rest gets bypassed back to the tank through the return line.
    Stock jetting should be used for a stock boat. You just need to adjust the high and low spd adjusters for your elevation, and check the piston wash to be sure it's getting enough fuel.

  10. #10
    Thanks again for all the help. I've got new fuel line, a triple pump, new fuel filters and new pilot jets on order. The local polaris shop checked and the STD should have 82.5 pilots while the non-STD was at 77.5. The 77.5 was in the first carb I pulled apart so they'll get replaced.
    The reeds all look good too. Hopefully it's almost there and I'll be able to get it out once or twice before I have to winterize it.

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