(800) 853-2651
SHOP NOW

Carb was leaking but not now

RedMF40

RedMF40

Well-known Member
I started my Massey after about a month of sitting. Ran fine but when I shut it off I noticed a fuel smell after awhile. Went to check and found a steady drip from the carb. It was getting dark and cold so I turned off the gas and went in for the night.

This morning I turned the fuel back on, started the tractor, and checked for leaks. Nothing. Yesterday it was dripping steadily from the bottom of the carb. First time for this, never had it happen before on this tractor.

Any ideas what may be happening? I thought I was going to get acquainted with the innards of the carb, but now it looks like it's back to normal. Thanks for any thoughts. Gerrit
mvphoto87324.jpg
 
A chip of paint, a rust flake, or a bit of flaked off varnish can wedge the needle valve causing it to flood/leak. The rule is to shut
off the fuel at the tank every time you leave the tractor. This may seem like a tedious chore but fires are easily started with gallons of
gas on the floor. Simply old is not new. A gravity fed carb has its fuel pump running all the time. Jim
 
I have had seen updraft carbs leak like that when they are run for a short time with the choke on. Gas condenses on the cold intake manifold walls and the flows back down after shut off and leaks out bottom of the carb. Also could be a pieced of debris stuck in float valve that washed out after you used it today.
 
Where exactly is it leaking from? There is a drain under the choke butterfly valve that will drip if you have to choke it hard to get it started. Also if the float is not closing the main nozzle will dribble fuel out the same drain. If its leaking elsewhere then there might be a seal that needs replacing.
 
Sounds like the float needle stuck
open for some reason. Likely from a
tiny piece of tar, rust, or dirt.
Additional run time and engine
vibration straightened it back out so
it would function correctly.
Could be just a one time deal.
Especially for a tractor that has sat
for long while. But, it could also
happen the next time you shut it off.
Just keep your eye on it. If it ends
up being kind of a one time deal, your
probably good to go. If it continues
to do this regularly, then an
inspection and perhaps a fuel system
flush might be in order.
 
As others have said, probably a piece of dirt under the needle. I never shut off t he gas on tractors but now I do as they are gravity feed and can leak like what
happened to you. I have installed a small ball valve (1/4 turn off to on so easy to use) in the gas line of my tractors. I get mine from McMaster Carr, mine ball valve.
 
I've got two TO 20's and a MHF Work Bull 202. They all do this occasionally. Dirt, etc. in the needle valve is the most common culprit.

I don't concern myself in the least about it. If I'm done with the tractor for any length of time I simply close the fuel shutoff when I turn the engine off. No leaks then.

If you forget to turn it back on it won't be long reminding you.

This post was edited by Carlmac 369 on 01/24/2022 at 02:24 pm.
 
Any carb that drips gets an inline gas solenoid shutoff.
I have one
cvphoto115192.jpg

on Farmall, Jubilee, both terramites came with them.
Any lawn mower carb that drips gets one.

All it takes is one tank of gas on the floor and the solenoids
have been paid for plus interest.
 
Thanks for the replies. I can't say exactly where it was leaking from so I cleaned off the carb this morning before turning the fuel back on. Then it didn't leak when I got the tractor running and even after shutting it off.

I have the fuel shut off now at the tank, something I know I should have been doing all along but maybe this is a wake-up call. Good advice. And yes, I'll probably forget to turn it back on but I won't get far.

I'll monitor the situation, thanks again. Gerrit
 
I don't recall the gas tractors from my youth doing this, but they sure seem to now. It doesn't make any difference if it's a
freshly rebuilt carb or not. So, what's going on, I don't know. My Case VAC will leak very occasionally. I had an AC WD45 with a
rebuilt carb a few years ago which did the same thing. Just when I got complacent and trusted it, it would leak. I've got an AC
D15II which never bothers. (I just cursed myself!) I put new parts in a neighbors' Farmall 450 carb, and pressure tested it. It
occasionally leaks.
 
I had one on a little Farmall that would leak. but would not leak if you took the carburetor apart and put it back on, but would leak if you started the engine and shut it down. I fought this thing for over a year and finally found that the bowl gasket I had bought from International was missing a hole that served as a vent between the two halves. The hole was perhaps about 3/32 in diameter.
 
I have had them weeping gas through the needle and seat. I
assume a small piece of rust or dirt is preventing full
closing . I shut off the fuel and start it up and let it
run out. Then the float drops all the way down, no longer
pinching the trash. When I turn the fuel back on it
flushes it through the seat. Usually works.
 
You must log in or register to reply here.

Similar threads

J
Zenith carb
Replies
5
Views
470
Geo-TH,In
Geo-TH,In
D
Rebuilt Carb Leaking into the Manifold
Replies
8
Views
385
DRDuetarg
D
B
Ted 20 not firing up.
Replies
4
Views
308
used red MN
U
O
Odd running problem
Replies
16
Views
944
cjunrau
C
M
Zenith carburetor
Replies
7
Views
442
ken44520978
K
Tractor Parts Tractor Manuals

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Copyright © 1997-2024 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy

Back
Top