140 Zenith carburetor

[Bus Driver]

This engine runs really rich fuel mixture, no doubt about it. The original jet is fixed, Zenith #20-L, from the literature I have found. Apparently that jet is IH # 55 594 D, no longer available from dealers. And I have not found the # 20-L for sale. But # 53 786 D appears to be an adjustable main jet for this carburetor and it is available for purchase. I have seen Zenith carburetors with fixed and with adjustable main jets. Assuming that Zenith used the same basic body for several different models, converting a fixed jet unit to adjustable should be just a matter of parts swapping. I prefer adjustable jets anyway.
Can anyone confirm that 53 786 D will convert my unit to adjustable high speed jet?

[Eugene]

http://www.wisconsinmotors.com/partcata ... neswm.html

Link to down loadable Wisconsin engine parts manuals. Back of the manual for VF4 and V-465D engines is an extensive break down of Zenith carburetors. Big problem is that the manual lists the Wisconsin part number and the Zenith part number.

I think you may have the Zenith 61 or 161 series carburetor which was used on some IH A,B,C series engines. The Wisconsin VF4 instruction book and parts list has an extensive break down on that series carburetor.

[Boss Hog]

I do not no about the #s you posted , but I have changes non adjustable jets to adjustable ones from other Zenith carbs
Without any problems.

[Boss Hog]

You have to change the jet in the carb too not just take the plug out and put the adj. needle in.

[Bus Driver]

I do appreciate the good replies. One of the IH manuals lists this carburetor as a 68X7, which I assume is Zenith number as no such IH number can be found.

[Bus Driver]

Boss Hog, the idea of changing the jet plus adding the needle is the way I thought it would be. But the parts catalog for the 140 engine (ENG-1) page 41 shows only the needle assembly with no jet specifically for it. And the needle assembly is not illustrated, but is listed after item 38. On that basis, the needle appears to just be added to the existing jet.

[Boss Hog]

They have had a larger hole in the ones that I have changed. The ones with the plug has a smaller hole in it. The needle goes down in the jet a bit.
I am only speaking from my experience with them.

[Eugene]

Wisconsin Instruction Book and Parts List for Models TH, THD, TJD, has the parts break down for the Zenith 68-7 series Carburetor. The parts list has an adjustable main jet - actually 9 different jet sizes.

Problem is finding a cross reference from IH part numbers to Zenith part numbers.

If you have a Zenith assembly number (tag) on the carburetor the Wisconsin manual can give you the main jet size for that particular carburetor.

[artc]

and if that doesn't sort it out. www.carbsonly.com BFIC Fuel Systems 877-845-9000 ask for Carlos. as long as you have your tag numbers he can get you the proper parts. he hasn't failed for me.