leaky carb

Wed Dec 25, 2013 8:14 pm

when my cub sits the carb has a slow leak. I'm thinking that the needle valve is not completly shutting off fuel. I know that I can shut off the sediment bowl but that is a little bit of a PITA. Any chance there is an easy fix to this?

Re: leaky carb

Wed Dec 25, 2013 8:54 pm

Where is the leak appearing?

Re: leaky carb

Thu Dec 26, 2013 9:33 am

Could be crud/problem in needle valve and seat area, float level, or faulty gasket(s).

Easy fix. Carburetor clean up and repair. Not difficult.

Re: leaky carb

Thu Dec 26, 2013 10:10 am

If you haven't opened a carb before, you need to pull the halves straight apart or you'll snap off the idle tube.

Bob

Re: leaky carb

Thu Dec 26, 2013 11:50 am

I had the same problem.
Only owning my Cub for about a month and not knowing how much it was used previously, I assumed it just needed a quick cleaning, I figured, just take it off and take it apart. Wish I saw this post first, because guess what, broke the idle tube.
To my surprise, she still starts and runs without the idle tube, but figure I better get a new one and rebuild it correctly
Any suggestions on how to get the broken piece out? And where to get a new one? The idle tube doesn't seem to be a standard piece in a rebuild kit. It wasn't in the kit I bought from Wengers and they didn't sell one separately.
My carb isn't an original IH (no markings, so assume it is an aftermarket). I'm thinking I will just get an original used IH, rebuild that, and when I find an idle tube, rebuild this one as a back up.

Re: leaky carb

Thu Dec 26, 2013 12:28 pm

If you have a rubber fuel line, add a cutoff in the line. It would only cost a few bucks. If I let mine sit for a long time I cut the fuel off and the cut off is much easier to deal with than the sediment bowl cut off. That would patch your problem. As stated before it is not that difficult to go ahead and fix the carb.

As for the idler tube I have several that is broken off. The only time I notice it,if at all, is at the very lowest idle speed. They seem to idle at a lower rpm when the tube is intact.

Re: leaky carb

Thu Dec 26, 2013 1:19 pm

I followed Lurker Carl's procedure (http://www.cleancomputes.com/Cub/Mainte ... index.html) and now my carb does not leak. However, I still shut off the fuel at the tank and would recommend that as a safety precaution.

Re: leaky carb

Fri Dec 27, 2013 3:01 pm

bythepond88 wrote:I followed Lurker Carl's procedure (http://www.cleancomputes.com/Cub/Mainte ... index.html) and now my carb does not leak. However, I still shut off the fuel at the tank and would recommend that as a safety precaution.
Same here, and a fuel shut off wrench,( see the how to forum), makes it easy.

Re: leaky carb

Fri Dec 27, 2013 7:53 pm

I added a brass valve in the line that turns 90 degrees off or on because of arthritis in my hands. I had surgery on my right hand and now it's easier to turn it off at the bowl, which I do to run the carb empty.

Re: leaky carb

Wed Jan 01, 2014 12:04 am

I had the same problem with mine, I put in a plastic 1/4 turn fuel shut off valve in the fuel line. They only cost a few bucks, so that was the quick band aid fix to keep all the fuel in the tank from dripping out.. Then I picked up a carb rebuild kit at NAPA and fixed it right. I still have the 1/4 turn valve in-line and shut the fuel off and let it idle for a bit before shutting it down. if it's going to e parked for a while I let it run out of fuel completely. This pulls the float needle valve off the seat and prevents the rubber tip from taking a set from being jammed up against the seat with a full fuel bowl.

Re: leaky carb

Wed Jan 01, 2014 10:06 am

I can't get mine to stop leaking. I cleaned the carb in my ultrasonic sink. New float, new kohler needle and seat, new gaskets. still leaks. It could be like mine and not be an easy fix.

Re: leaky carb

Wed Jan 01, 2014 11:07 am

gusbratz wrote:I can't get mine to stop leaking. I cleaned the carb in my ultrasonic sink. New float, new kohler needle and seat, new gaskets. still leaks. It could be like mine and not be an easy fix.

Did you reset the float to the correct measurements after replacing the float, needle and seat?

Image

Re: leaky carb

Wed Jan 01, 2014 11:54 am

Bench test for source of the leak:
Eugene wrote:Hose barb to fit carb inlet, clear plastic tubing to match the hose barb, funnel small enough to fit inside the clear plastic tubing and a bottle of rubbing alcohol from the dollar store.

Remove carburetor top, turn and block upside down on bench with hose barb, tubing and funnel attached. Funnel above carburetor, fill with alcohol. Observe needle valve area and remainder of carb top for source of leakage.

Re: leaky carb

Sat Jan 04, 2014 12:43 am

Another thing to check for is a hole in the float. I took my carb apart several times, and did a full rebuild before I thought to shake the float. It was full of gas. Replaced with a float from a spare carb, and it hasn't leaked for two years.

glenn

Re: leaky carb

Sat Jan 04, 2014 12:47 pm

well have not done anything with this yet, need the cub for moving snow this time if year. I added a little brake line clamp on my fuel line to shut off fuel. Went to start it today and fuel was running out of the air inlet to the carb. Plan to rebuild the carb after winter passes. Where is a good place to get a carb rebuild kit or new/rebuilt carb?
thanks
Bob