Mikuni Carb Leaking

  1. Welcome to 6x6 World.

    You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

    If you have any problems with the registration process or your account login, please contact us. Looking forward to seeing you in the forums and talking about AATVs!
+ Reply to Thread
Results 1 to 4 of 4

Thread: Mikuni Carb Leaking

  1. #1
    Join Date
    Sep 2012
    Location
    Dillsburg, PA
    Posts
    104

    Mikuni Carb Leaking

    Hi Everyone, I have a Attex with a 400 JLO and a single Mikuni Carb in it. I have a brand new Mikuni pulse fuel pump (Rectangle type). The pulse hose is black rubber and I have located it where it has a length of 16" to 28" from the vacuum port. My problem is that when I take it for a drive after 10 minutes, gas is overflowing from somewhere on the carb - not sure where. At idle it does not happen. I have new floats and a new Needle valve and it still overflows. I have adjusted the float level several mm higher than spec and it still overflows. I am at the point of ordering a new carb. Does anyone have any ideas? What carb size would you recommend I replace it with? Thanks.

  2. #2
    Join Date
    Nov 2020
    Location
    Southwestern Ont Can about 5 miles from Lake Huron just north of the town of Goderich.
    Posts
    201
    Anything I have had to do with a JLO carb was a Tillotson. I am thinking that the carb has been upgraded to the Mikuni. Is there maybe a return to tank outlet? Is the pump the proper one for that carb? At idle you will be pumping less fuel due to less vacum but also your hose length will problably cut the vacum pumping even less fuel thereby giving the engine enough fuel to run but not enough to flood out the carb. Don't know enough about the pump and carb setup but it is where I probably would start to trouble shoot. Could very well be sending you on a wild goose chase. A lot smarter people on this forum than me will maybe chime in.

  3. #3
    What Mikuni carb is it?

    It's possible the carb is installed upside down?
    On the mikuni I have installed on a 340 JLO the pump section needs to be on top, otherwise the carb will leak out the inlet.

  4. #4
    john how in the world could you ever say'''' to him or ask is the carb installed updside down!! thats impossible!! the throttle mechanism goes right threw the top for christ sakes!!! you cant turn a mikuni upsides down

+ Reply to Thread

Posting Permissions

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