Farm Equipment - Carb Leaking Gas

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Carb Leaking Gas

Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=189077
Printed Date: 07 May 2024 at 3:48am
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: Carb Leaking Gas

Posted By: cfciii03
Subject: Carb Leaking Gas
Date Posted: 24 Jun 2022 at 1:41pm

1955 Model B.

Zenith carb #212845.

Carb has been recently professionally rebuilt with new needle, seat and float. Float level meets specs. still leaks gas out of the air intake. going crazy with this.

any thoughts ?

Replies:

Posted By: DrAllis
Date Posted: 24 Jun 2022 at 1:48pm

My thoughts are if I had rebuilt it for you, I would expect you to bring it back to me.

Posted By: PaulB
Date Posted: 24 Jun 2022 at 3:30pm

Maybe the only reason it was a "Professional" rebuild is the fellow got paid. Definitely not quality workmanship. I'd send it back to the "professional" and tell them to fix it right.

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If it was fun to pull in LOW gear, I could have a John Deere.
If you can't make it GO... make it SHINY

Posted By: steve(ill)
Date Posted: 24 Jun 2022 at 5:28pm

Fred, what they are saying is the float is stuck, or the inlet valve is not seating and the gas is getting TOO FULL in the bowl.. That is the only way for gas to rise up and run out the air inlet port.... Your not SHUTTING the gas off.....

Floats can stick on the side of the bowl, stick on the gasket,, get a hole and SINK, or the little valve can LEAK by on the gas inlet..

If you turn the carburetor upside down when shipping, maybe the float got "stuck"... you can try rapping the carb a couple times with a small ball pean hammer and see if the float "drops to normal" and is OK after that... If it continues to leak, it needs to be looked at internal.

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Like them all, but love the "B"s.

Posted By: DrAllis
Date Posted: 24 Jun 2022 at 5:32pm

Workmanship could have been fine. There's always a chance the needle/seat are defective even tho they may be new.

Posted By: mdm1
Date Posted: 24 Jun 2022 at 6:25pm

Gerald J (sorry to hear of his passing) used to say to turn the carb upside down and blow into the gas inlet. If you can't blow (just with you mouth) air into it the float is working. Turn it right side up and you should be able to blow air into it. Also if the needle valve has a rubber tip I have tapped it into the valve with a hammer to create a seat on the needle. Hope that makes sense. Good luck.

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Everything is impossible until someone does it! WD45-trip loader 1947 c w/woods belly mower, 1939 B, #3 sickle mower 1944 B, 2 1948 G's. Misc other equipment that my wife calls JUNK!

Posted By: Steve in NJ
Date Posted: 24 Jun 2022 at 8:59pm

As Steve mentioned, there are so many little things that could cause that senario you could pull your hair out. The Nitron needle does a great job in shutting off the fuel at the inlet, but if a minute piece of dirt passes through, it'll stick like glue right to the Nitron needle and you have fuel creeping through! A thing you could try is take a piece of super fine steel wool and burnish the brass barrel part of the needle. If the needle is a tick tight in the bore, there could be a little burr on the brass that's hanging it up in the seat bore. A little polishing of the needle barrel may do the trick... HTH

Steve@B&B

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39'RC, 43'WC, 48'B, 49'G, 50'WF, 65 Big 10, 67'B-110, 75'716H, 2-620's, & a Motorhead wife

Posted By: mdm1
Date Posted: 25 Jun 2022 at 6:39am

I've taken a q-tip in a drill with alittle metal polish and polished the barrel.

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Everything is impossible until someone does it! WD45-trip loader 1947 c w/woods belly mower, 1939 B, #3 sickle mower 1944 B, 2 1948 G's. Misc other equipment that my wife calls JUNK!