: My friend Dave just inherited a '33-'37 WC with
: a gummed up carb. He's soaked it in lacquer thinner and blown out the passages, but it still
: only runs if you mostly cover the carb mouth : (choking it) with your hand. However, on
: closer inspection, looks like not all passages were cleaned. There's a jet visible in the float bowl wall that Dave says he's not been able to get
: loose; thus the passage behind it might be partially clogged. Looks like it might control flow in the main circuit lying in the venturi - it leads to it. Anybody know if it does? Dave
: got the needle jet which threads into the bottom of the carb out and clean. I am guessing the main circuit might have a fixed jet (governing max richness) and an adjustable needle jet (allowing you to lean it out for running under light load). Anybody know the true setup on these things? Thanks!
: Tractor has been resurrected pretty well, except for the carb. Love that 1300 rpm max speed.
youre on the right track but it sounds like you need to do a couple of things. first, if your friend cant get the brass jet out, just use a spray can of carb cleaner and stick the tube of the can right down in the jet. be patient and run plenty through to melt out the gunk.
then, check the float level. with the upper half of the carburetor turned upside down and the float and needle in place the float should be level or slightly inclined upward in this
inverted position. if the float level is way off, that could be your problem also.
then, with these chores done, and the carb. on the tractor, you can rough set the carb before startup.
the lower main jet you referred to should be screwed all the way in, then backed out two and one half rounds.
the air jet at the top should be one and one half rounds out from bottom, however you may wind up with it screwed all the way in before you get your idle sounding like you want it. for some reason, with age this adjustment has to be decreased. then, play with the adjustments from there to maximize your power. you dont want to tinker with the carb from one job to the other as i think you implied in your letter. good luck, and email me if i can help further. regards, grapeape