zenith carburetor pictures

hello checked the float level on my super-a picture 1 showes fuel level at the usa stamped on the side . picture 2 showes fuel level at bottom of carb when running, never checked level while running before don,t know where the level should be when running, picture 1 looks like it is about right but book don,t tell me where it should be any help out there

Just a question, but has it been a while since this unit has run? If yes, you need to be sure the fuel line is clear and there is no moisture in the gasoline. Drain and clean the sediment bowl and blow out the line. Drain the bowl on the carburetor and try again. The old 200 we had when I was a boy did not run well after setting up and we would have to go through this proceedure every spring. It would be best if you could do some work and run the tractor after you get going. When it starts runing bad again clear the sediment bowl, the fuel line, the screen into the carburetor, and drain the carburetor bowl. Install the fuel line backwards from the sediment bowl so that you can verify that a good flow of fuel passes when you open the valve. Run the tractor until it runs bad again. It may take two or three trys to get it completely clear and yes you do have to do all the above each time. Runing lean at high speed could imply that there is a blockage in the fuel line. IF YOU HAVE A FUEL FILTER TAKE IT OFF BECAUSE THAT ALONE WILL TEND TO MAKE IT RUN LEAN AT HIGH SPEED OR UNDER LOAD. If you have a loop in your fuel line that can cause problems as well. This is in addition to making sure all the issues with the carburetor are settled as discussed by others.

The fuel line on hi tractor cannot be reversed and i have used inline filters for many years and the only problems i have had is they do get full of dirt and plug and this is after the screen in the sediment bowl. I use a rubber line and a quick chech is easy to tell when they are plugged but with a good filter those engines run just fine. When the filter gets plugged it is just common sense the engine wont run but the filter has done its job so dont tell me i cant use them after many yrs of experience.

the steel line is supposed to have a loop in it to prevent the line from cracking from vibration.if your line is plugged why not just blow it out with air?

ran tractor all summer, last week i put new pistons @ sleves, bearing had the head redone, nos carb, points, plugs, wires, cap, rotor, blowed out tank and fuel line , new filter in orignal fuel bowel idles good but still has a miss in it every 15 20 seconds. it was missing like this all summer, but not at high speed seems to run a little better with the choke out a little, hopeing that someone would know about the fuel level keith

I found out years ago, when checking fuel level like that it will drop way down when running due to the pressure differential in carb when running so you can not get a accurate reading running so that level you are getting would be normal. I don't know the exact fuel level in that carb, checked a lot of M's , H's etc but not the smaller tractors.

Just be sure that the inline filter is for gravity feed systems.

if it's popping every few seconds, I can share two things that have worked for me.

1. Drain the fuel tank, when it stops draining, place a catch basin under the sediment bowl, and remove it from the tank.
A lot of water / fuel will come out, so be ready. Clean as much residue as possible (safely) and refill with fresh gas.
Condensation will build up to the point to where it will come over the top of the stand pipe on the sediment bowl, and water in the fuel will cause a miss.

2. open the main jet on your carb 1/2 turn at a time, rev the engine from idle to max a few times, and see if the miss clears, keep track of how many 1/2 turns it takes. This will be your max setting for working the tractor.
Turn back in 1/2 to 2 turns for light duty, this is your "light setting".

Get rid of that hose. Set the float to the height specified in the instructions that comes with a kit, or look it up in a shop manual. If the float is adjusted to specs, and the tractor still doesn't run like it should, you need to dig deeper. That clear vinyl hose is telling you nothing.

hello, i have a cub repair manual that showes to check fuel level with the clear hose because some floats are not the same weight and not made the same , so i would think that you can check any carb like this as long as you know where the float level should be keith

(quoted from post at 13:54:25 12/07/11) hello, i have a cub repair manual that showes to check fuel level with the clear hose because some floats are not the same weight and not made the same , so i would think that you can check any carb like this as long as you know where the float level should be keith

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You can spend countless hours playing that guessing game, or you can set the float height according to specs and be done. If you have nothing but time on your hands, go ahead and play the guessing game. I do not have that much spare time.

course you set the float level by the factory specs but the way you check the level to see if it is right is to use the fuel level hose , unless you have z-ray vision and can see through the carb itself keith

The hose is a good method to check actual fuel level due to all the variations of float conditons etc. You have to do it right away after shutting it off though so if you have any leakage you will show a higher level than you are actually running at and this will also show you if you do have any leakage raising fuel level when shut down.

i with you pete on the fuel level hose . i just don,t know where it should be on this carb. i got a cub book that shows where it should be on it but can,t find anything on this carb thanks keith

From your picture number one of the fuel level, I would take a swag at it being very close to correct from my experience with other carburetors. If the float is adjusted so it is parallel to bowl mounting surface when inverted I would just leave it there. It sounds like you have a main jet that is too small. There are so many different carburetors that I can not tell you exactly how yours is. If you have an old carb like it I would take the main jet out of that and try it. I am assuming main jet is screwed in on that one or is part of the main nozzle. I have a set of wire gauge drills that come into play after I have ruled out all other possible problems. Newest fuels do not always perform same as the older gasoline carb was calibrated for. Not much help I guess.

hey pete , i think your right about float level, will check out the jet and see what i can figure out, will let you know what i find. thanks keith