1. Hello Guest. You have limited privileges and you can't "SEARCH" the forums. Please "Log In" or "Sign Up" for additional functionality. Click HERE to proceed.

Idle and synch

Discussion in 'XJ Technical Chat' started by oak450, May 20, 2009.

  1. oak450

    oak450 Member

    Messages:
    107
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    The foothills of Oregon
    I can't get my idle under 2000 if my carbs are synched. The idle screw is all the way out and won't go any lower. Any suggestions?
     
    oak450, May 20, 2009
    #1
  2. Kyrrinstoch

    Kyrrinstoch Member

    Messages:
    120
    Likes Received:
    0
    Trophy Points:
    16
    Have you checked to see if you have an air leak around the carb boots and/or the throttle control linkages?

    If any of those are leaking, it may cause this.
     
    Kyrrinstoch, May 20, 2009
    #2
  3. oak450

    oak450 Member

    Messages:
    107
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    The foothills of Oregon
    Haven't checked for an air leak. How do you do that?

    Also interesting that one cylinder is sucking way less air, according to the manometer. All the other ones synch up fine, but to make the #4 happy I have to bring the rpms way up. Guess that would be the one to check for leaks.
     
    oak450, May 20, 2009
    #3
  4. rpgoerlich

    rpgoerlich Member

    Messages:
    837
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    Katy, Tx
    Got a good YICS tool inserted when trying to sync?
     
    rpgoerlich, May 20, 2009
    #4
  5. dpawl31

    dpawl31 Member

    Messages:
    873
    Likes Received:
    11
    Trophy Points:
    18
    Location:
    NH, USA
    I am 60% sure you have the same problem I had...

    Did you bottom your sync screws out BEFORE you did a bench sync?

    They need to start ALL the way at the bottom, and use the idle screw to JUST crack the #3 butterfly open.
     
    dpawl31, May 20, 2009
    #5
  6. moonfriedpotatoes

    moonfriedpotatoes Member

    Messages:
    239
    Likes Received:
    1
    Trophy Points:
    16
    Location:
    Montana
    use an unlit propane torch to check for leaks. Hold near an area; if idle increases then you have a leak.

    on XJ650's and 750's (hitachi), new carb boots can be made from 1.5" rubber plumbing couplers, if that's where your leak is.
     
    moonfriedpotatoes, May 20, 2009
    #6
  7. oak450

    oak450 Member

    Messages:
    107
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    The foothills of Oregon
    Got new carb boots last year, don't think that's the problem.

    I'm using chacal's tool, never failed me before.

    Think I'll try taking off the carbs and bench synching them again, like dpawl says. I'm probably maxing out the screws.
     
    oak450, May 20, 2009
    #7

Share This Page