Jump to content

Vote for Tractor of the Month
Garden Tractors and Parts on eBay

- - - - -

Walbro Lme Main Jet "workaround"

  • Please log in to reply
1 reply to this topic




  • Senior Member
  • Member No: 154
  • 129 Thanks
  • 122 posts
  • Location: Cambridge, Ontario

Posted May 02, 2012 - 10:09 PM

I stumbled across an unusual way of getting a Walbro LME to "work" - after a fashion - that may be of interest to others with carb problems.
I had cleaned out the Walbro LME 36 carb on an HH120 and installed it - the engine idled smoothly but hunted badly at high revs . Checked the governor, throttle cable, float setting, needle valve seat but couldn't find the cause. It was only when I was comparing ithe carb with another one that worked that I realised the main nozzle was backed out about five turns. This was not quite enough to block the fuel inlet at the bottom, but enough to expose the idle intake hole in the carb body above the nozzle's outer threads. As a result, fuel was able to run into the nozzle, out the air holes and up the idle circuit, so the engine idled nicely. However, the high speed needle had to be backed out as well and was so loose that air leaked in at high revs - causing the hunting. (and it leaked fuel from the main needle as well).

I had not touched the main nozzle before and guess that the PO had set it like this because he could not get it to idle properly when the nozzle was screwed right in. After removing the nozzle, cleaning out the idle hole, screwing in to the proper depth and realigning the small idle hole in the nozzle with the hole in the carb body, It now runs smoothly at idle, high revs and all points in between.
  • MH81, caseguy, Alc and 1 other said thanks

#2 caseguy OFFLINE  


    Connoisseur of Rusty Junk

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 906
  • 1,624 Thanks
  • 5,600 posts
  • Location: Edinburg, PA

Posted May 03, 2012 - 08:18 PM

It's always great to hear of a solution for one of the "ghosts" that we chase sometimes. Thanks for passing it along!