Farmall B - Carb

[Dave H (MI)]

I am sure you are all as relieved as I am that the tag line does NOT say "fuel line"!

The missus got back from wally world about an hour before I had to leave for the fair with news that the battery had a dead cell and she traded it on a new one. We put it on the B and it roared to life...well not roared exactly...it sputtered a little while it adjusted itself to all the new parts but THEN it did roar to life.
I have full range on my throttle lever now and really no idea why since I made virtually no change to the governor when I did that adjustment.
The tractor has good operation at high rpms going up hill and down and idles down to a pretty smooth but high idle. Take the throttle down the last couple of notches and you get a low idle with a lot of sputter, missing, whatever you call it. Odd thing, and I am unclear on this, the idle adjustment screw has NO effect still on the idle speed. All the way in or most way out is the same. So follows is the status:

There is no main jet adjustment on this Zenith carb. There is an idle screw set out one full turn and a screw on the throttle arm set out 1.5 turns (keeps the throttle shutter open a crack)...both exactly as described in the service manual. Air filter is cleaned and new oil and new rubber joint to carb. Gas line and all screens are new as is sediment bowl. I am ready for my next instruction. What adjustments do I need to make?

 

[ScottyHOMeY]

Don't touch a thing!

See how she runs, just running around and with any kind of load you can find to put on it.

The screw on the throttle lever is just for speed, so if you haae any kind of tAchometer that you can get onto it to check the idle speed, you can't really get into any confusing or irreversible trouble fiddling with that one.

Of more interest is the idle air mixture screw. If you're at The default one turn out and it's running, I would say don't bother it any for now.

I'll bet she sounds good!

 

[Wayne in MN]

The idle air screw should be turned in or out until the engine idles smoothly. Any setting in a book is just a starting point for further adjustments.
If the idle air screw is not able to do it's job, then you need further cleaning of the idle circuit in the carb.
I have cleaned and adjusted more carbs than I can count in the past 50+ years. They can be "interesting" sometimes.
Send an e-mail if you need further info.

 

[Janicholson]

Yippeee!!!
The battle has been won and only a bit of PTS is left. Let it run a bit rough for a week then we will tell you how to find the little slots and bleed orifices at the edge of the throttle plate when it is closed that are still a bit plugged up, or the float is set to low. But we will not tell for a week. JimN