Ford LRG423 - Zenith Model 33 carb rebuild advice

[BrownBear]

1997 JLG 40H with Ford LRG423 dual fuel. A lot of difficulty starting, spark ok, so suspecting a carburetion issue, I picked up a rebuild kit for the Zenith Model 33 carb.

It turns out I don't understand the idle circuit on this carb. There is an idle port and screw at the base and two plugs below and beside that screw. The exploded diagram that came with the carb kit indicates these are "not normally removed for service". From my motorcycle carb experience I am used to gaining access to and removing a pilot jet and often finding it gummed up. I am reluctant to drill out these plugs, but my instincts are that to be really confident in my rebuild I need to get cleaner and maybe wire through more of the idle circuit than I am able to access through the idle screw port.

If you have done cleanings / rebuilds on the Model 33 or a similar Zenith, how did you make sure your idle circuit was doing the right thing?

 

[excavator]

I'm also working on a 40H with carb problems. I've had this one on and off so many times through the years but this time I can't seem to do anything to make it run. I've never put a kit in it, just ran carb cleaner through it and blew it out with air. I found a place on-line called carbsunlimited www.carburetion.com that sells a new one for $579.00 which seems to be a pretty good price, especially since the choke assembly alone cost me over $200.00 a few years ago.

 

[Tenwheeler]

I do not like those. Last one I worked on was on an overseas forklift. Had worked on it over the years. The last time someone was adjusting it with a hammer and physically broke it. Dealer said a new one was 900 and some odd dollars. Pay us and we will order it. No guaranteed delivery date but maybe a month or two.
Found a VW bug carb that was very similar for about $200 new. Had to make a one inch spacer with flanges on both sides. That rotated it a 1\4 turn. Had to modify the arm on the shaft so it had an arm on the other side of the shaft.
It did not have that vacuum controlled accelerator pump and worked great.
Thank I would get a kit and do as excavator said first.
Believe Dorman makes a manual choke conversion for those.

 

[gatorsby7]

the Ford LRG423 Service Manual has a detailed section on the operation and service of Zenith #33 carb. you should be able to google a free download of this manual.