Close
Login to Your Account
Snowmobile Fanatics - Snowmobile Forum - Powered by vBulletin

CHASING THE IDLE

This is a discussion on CHASING THE IDLE within the Polaris forums, part of the Brand Specific Snowmobile Discussion category; I'm doing a bit of work to a buddy's sled for him, and I'm having a hell of a time setting the idle up on ...

Results 1 to 9 of 9

Thread: CHASING THE IDLE

  1. #1
    Senior Member
    This user has no status.
     
    EarnhardtNorth's Avatar
    Member #
    18474
    Join Date
    Jun 2007
    Posts
    229

    I'm doing a bit of work to a buddy's sled for him, and I'm having a hell of a time setting the idle up on this thing! It's a '98 XCR 600. I have owned triples since 1993 and have set up the carbs on countless sleds. I have the Uni-Sync tool to balance air flow and I'm chasing my tail?
    I set the cables up and set the idle. It wants to sit around 1100 to 1250, I'd like it higher but that seems to be a fine line between that and too high. 2200-2400..no in-between.
    So I re-adjust and we're back the 1200 mark. Give the throttle a couple burps and it's up to 3000 and won't come back down.
    Hit the kill switch, lift the kill switch, pull the GO cord and it idles back at 1200? Burp the throttle and back to 3000, and it won't settle back down! And this dog and pony show is repeatable time and time again!
    I'm thinking it's something in the cable, but why it doesn't go right to the high idle after shutting it off has me miffed.

    I have rechecked the set up for the slides and all is the way it should be there. My buddy cleaned the bowls and jets, so I didn't see in there, but he did watch me do a 440 sled the night before. What could he have screwed up down there that would make it act like this?

    Any thoughts, before I pull the carbs completely off again?

  2. #2
    Senior Member
    This user has no status.
     
    427cobra's Avatar
    Member #
    32088
    Join Date
    Mar 2010
    Location
    IL
    Posts
    153
    Bad crankseals? Possibly dirty pilot jets?

  3. #3
    Senior Member
    This user has no status.
     
    Ugly_old_Poo_kid's Avatar
    Member #
    17965
    Join Date
    Mar 2007
    Posts
    9,767
    Newer liberty twins are like that. Kick the throttle at idle, and it sits higher for a while then drops back down. I think that's a response thing, if you're riding, you're more likely to get back on the gas and the higher idle will have a faster response.

    Let it sit a bit at idle and see if it drops back down.

  4. #4
    Senior Member
    is Waiting...
     
    KRSS144's Avatar
    Member #
    18696
    Join Date
    Jul 2007
    Posts
    1,791
    ^thats all I do with my XCR, let it idle high for a few and then hit the choke really quick to drop it down and than she purs like a kitten. Stays right at 1900-2000rpms just how I like it. If I dont kill it down from the high idle it will take it a little to come down but it does come down on its own.

  5. #5
    Senior Member
    This user has no status.
     
    EarnhardtNorth's Avatar
    Member #
    18474
    Join Date
    Jun 2007
    Posts
    229
    How many minutes are we talking about, for it too drop back down? Yeah I was wondering if something is wrong in the bowl, or bad carb boots, crank seals? The sled runs really good though. Starts fine, sounds right. Just this idle thing. I'm going to look at it again tonight. I'll let you's know if I find anything obvious.

  6. #6
    Senior Member
    This user has no status.
     
    CanadianXCR's Avatar
    Member #
    6839
    Join Date
    Dec 2004
    Posts
    2,678
    If its doing that when its cold it's normal. Let it get up to normal operating temp and it shouldn't do it as much, it should come back down on its own after less than 30 secs. My 650 Indy used to do this, everything was setup correctly.

  7. #7
    Senior Member
    is Waiting...
     
    KRSS144's Avatar
    Member #
    18696
    Join Date
    Jul 2007
    Posts
    1,791
    Im not talking minutes here...30 seconds max. I know a few guys with the big twins that do the same thing.

  8. #8
    Member
    This user has no status.
     

    Member #
    12200
    Join Date
    Feb 2006
    Posts
    52
    Quote Originally Posted by EarnhardtNorth

    I'm doing a bit of work to a buddy's sled for him, and I'm having a hell of a time setting the idle up on this thing! It's a '98 XCR 600. I have owned triples since 1993 and have set up the carbs on countless sleds. I have the Uni-Sync tool to balance air flow and I'm chasing my tail?
    I set the cables up and set the idle. It wants to sit around 1100 to 1250, I'd like it higher but that seems to be a fine line between that and too high. 2200-2400..no in-between.
    So I re-adjust and we're back the 1200 mark. Give the throttle a couple burps and it's up to 3000 and won't come back down.
    Hit the kill switch, lift the kill switch, pull the GO cord and it idles back at 1200? Burp the throttle and back to 3000, and it won't settle back down! And this dog and pony show is repeatable time and time again!
    I'm thinking it's something in the cable, but why it doesn't go right to the high idle after shutting it off has me miffed.

    I have rechecked the set up for the slides and all is the way it should be there. My buddy cleaned the bowls and jets, so I didn't see in there, but he did watch me do a 440 sled the night before. What could he have screwed up down there that would make it act like this?

    Any thoughts, before I pull the carbs completely off again?
    Check to see that the choke cables are adjusted properly and also make sure the choke cable is free and not clamped down or clamped together with zip ties. It will bind the cable and open the plungers. Also make sure the throttle cable routing is the same way, free/loose with no zip ties that are tied tight! Also pay attention to the throttle cable/choke cable when the hood closes. If the cables are not routed properly, the hood can press on the cables when you close it and it will mess up your carb sync and can start to open the choke plungers! Also do a compression check on all 3 cylinders to be sure you don't have one cylinder down or a stuck ring. Lower compression on one cylinder can really mess up the idle and play with your mind. I'm speaking from experience!

  9. #9
    Senior Member
    This user has no status.
     
    EarnhardtNorth's Avatar
    Member #
    18474
    Join Date
    Jun 2007
    Posts
    229
    Thanks for all the info guys. I've been tied up with work and what not but hope to get back to it on Tuesday. I'll report back.

Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •