fuel filter ??

Thu Jun 05, 2014 10:48 pm

Hi,
I just recently bought a 1950 cub. It usually starts real easy but seems to gain no power in 1 gear no matter how much you move the throttle. And tonight it will not start, or when it does start it idles for a little bit then dies, no response when you increase the throttle when idling either. Could the fuel filter be clogged or bad? It looks like a fairly new filter. Any help is appreciated.

Thanks

Re: fuel filter ??

Thu Jun 05, 2014 11:05 pm

Kansasdad, Welcome to the Forum. You'll need to check your fuel flow from the tank to the carb. First remove the drain plug from the bottom of the carb bowl and make sure you have a good steady flow of gas from there. If that is good, remove the main jet (brass hex head near the bottom of the carb). Run a fine copper wire through it and blow out with air. If you don't have flow to the carb, there is a screen in the inlet, or you may have debris in the sediment bowl or in the stand pipe that extends up into the tank on the top of the sediment bowl. If you have an inline filter, it needs to be a gravity feed kind, or fuel will be restricted going to the carb. Let us know what you find.

Bob

Re: fuel filter ??

Thu Jun 05, 2014 11:30 pm

Thanks for the info Bob...I'll see what I find tomorrow and get back with you all.

Re: fuel filter ??

Fri Jun 06, 2014 12:31 pm

After looking it over again today I am getting fuel to the carburetor,but not through the carburetor. I don't see any gas shooting in when you try to start it. Does anyone have any suggestions.

Re: fuel filter ??

Fri Jun 06, 2014 1:05 pm

If you have gas flow,then the screen in the gas inlet may be clogged, or the needle valve is stuck. For both, you'll need to remove the carb.
-turn off the gas at the sediment bowl
-loosen the hose clamp and remove the air intake
-remove the two nuts holding the carb to the manifold and drop the carb off the manifold
-rotate the carb to facilitate removing the cotter pins holding the choke and throttle shafts, remove the shafts from the carb
-you can check the inlet screen which is recessed into the gas inlet
-to open the carb, remove the four machine screws, then carefully pull the carb straight apart. There is a thin (1/8" x 2") idle tube that is easily broken if the carb is "cracked"open. Let the float drop and see if the needle valve is dropping freely also.

Bob

Re: fuel filter ??

Fri Jun 06, 2014 1:36 pm

I would try cleaning the main jet before that.

Re: fuel filter ??

Fri Jun 06, 2014 1:39 pm

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