Carburetor leaking
 

I cleaner up the zenith carburetor put in new gaskets everything was running great, went to start it 2 weeks later and it won't start keeps dying like it was not getting any fuel, I added gas thinking gravity feed low on gas, got it running backed it out got 10 feet and died would not start again. Now when I turn on the gas valve gas is pouring out of the carburetor. Any thoughts?

Re: Carburetor leaking
 

Has all the symptoms of float valve in the carb not closing properly. Possible cause is float has sunk and allowing excess fuel into the carb bowl.

Re: Carburetor leaking
 

Tap the top of the carb above the float a couple times with a small hammer or large open end wrench. That will unseat a stuck needle. Then start the engine.
Marshall

Re: Carburetor leaking
 

take the carb apart and start over using a good model a carb rebuild manual. take your time.
don't wack it with a hammer.

Re: Carburetor leaking
 

If this is the case they can be repaired. I have soldered 2 and both have and still do work fine.

Re: Carburetor leaking
 

Just to be clear, I didn't say "whack" the top of the carb. I said "tap" the top of the carb. That has loosened up many a stuck needles without damaging the top of the carb. Finesse is the key here, not brute strength or a BFH. :) 'Just did that to a friend's 1931 Coupe last week and the chronically sticking needle freed right up, stopping an irritating leak. He was a happy camper after that.
Of course, as has been recommended here, it doesn't hurt to disassemble the carb for cleaning and inspection. But the way needle and seats are made today, the inside of the carb could be surgically clean, yet the needle will occasionally stick in the seat. Could be the poor quality of gummy gasolines we are obliged to buy these days or some fine particles of grit have found their way from the gas tank into the carb. I have even had sticking needle problems with the very expensive new Viton tipped needles. I never had any luck with the ball bearing configuration, the so-called Gross needle and seat. Are these even being made anymore? I try to find original needle and seats whenever possible, but they are hard to scare up. I am still kicking myself over not buying a compartmentalized cardboard Zenith Corp box that contained all the jets and gaskets for rebuilding the Zenith carb. It was new old stock and the owner said he got it from a Ford dealership in the 1950's. Its mechanics had used such boxes when rebuilding customers' carbs. Can you imagine how good the quality of THOSE parts was!?! $25 and I passed on its purchase. Dumb, dumb, dumb me!
Marshall

Re: Carburetor leaking
 

6 possible causes of carburetor leaking described here: https://model-a.org/symptoms.html

Re: Carburetor leaking
 

Sometimes carbs will leak after bouncing around on their side in a delivery truck.

If leaking ...
1. Before "wacking" turn off the gas valve.
2. Start engine (with gas valve closed) and rev it up several times (most often the vibrations will loosen the float valve needle).

Usually there is enough gas in bowl to rev it up several times.

3. Turn gas valve back on.



Tapping is better than Wacking!

When tapping it is better to tap on the 5/8ths hex head of the drain plug.

That way the paint is not damaged and drain plug can be replaced if dented.

Re: Carburetor leaking
 

1. Dirt in gas tank will get under the float valve seat and prevent it from turning off.

2. Old stinky, gummy gas will make float valve needle stick.

Re: Carburetor leaking
 

I might add one more possible cause for a leaking Zenith to the model-a.org list. This actually happened to me (doesn't everything?) years ago. Someone had overtightened the brass plug at the bottom of the main jet passageway, cracking the metal. A little spider web crack spread from the threaded hole just past where the plug's gasket sits. Even the threads were cracked, where the crack began. Because of its location underneath the carb and the fact that it was difficult to see until the plug and gasket had been removed - in addition to cleaning the lower body down to bare metal - the carb would drip from the lowest point on the carb. I had tried new gaskets and a new plug, thinking the threads on the old plug were worn and gas was escaping past them. Nope. After finally removing the plug and gasket and cleaning down to bare metal, the crack was easy to see. It was that crack that was cause of the leak.
For those out there with a chronic dripping Zenith, you might check for a crack emanating from that main jet hole after eliminating the usual suspects. Freaky and not commonly encountered, but it happens.
Marshall

Re: Carburetor leaking
 

I am new to Ford Barn having just acquired a 1930 Coupe. When I got the car, the carb was leaking from the bowl vent. I rebuilt the carb using a standard rebuild kit and believe I fixed most of the leaking issues, but I'm not sure the float fits correctly. The new float I received is narrower at the mounting point, where the pin goes through, and has a lot of side to side play. That doesn't seem right to me, but I haven't found anything that details if the side to side play is ok or if it needs to fit tightly. Has anyone encountered that when replacing the float?

I also found I needed to replace the fuel shut off valve because it was not completely shutting off fuel flow. I tried to replace the fuel shut off valve with a new one and the pencil screen that is supposed to push into the tank side fitting would not fit. The replacement inside fuel line I received is almost 1" too long as well.

Am I receiving poor parts or is this par for the course with replacement parts? Any guidance is appreciated. I really just want to get out on the road!

Re: Carburetor leaking
 

OutlawDR, is there a local club near you? Can't beat a local source of advice. Tapping into experience will get you driving sooner. Your replacement parts should fit. Your avatar doesn't show your local. If your lucky, a good local source for parts is handy. I use original internals when I rebuild a zenith, they work.

Re: Carburetor leaking
 

I just went through this with my old carburetor.

Like everyone else is saying, first off make sure the float is good. I had set the float height on mine to the correct spec was still getting leakage. I ended up replacing the needle with one of those viton-tipped needles as well as the seat and that ended up fixing my problem. The original needle was all metal in mine

Re: Carburetor leaking
 

There's several different carburetors that fit on the Model A. You may have ended up with a float that was made for a different carburetor.

Re: Carburetor leaking
 

as most others suggest the likely causes of the the non-opening together with the non- closing of the valve in your case is either A. a poor valve, or B. float getting caught on casting, or C. the float hinge hinge poor so that float and valve don't "mate" well . But for full solution follow "old ugly's" advice #4

Re: Carburetor leaking
 

I did reach out to the local Model A club, but unfortunately, they did not respond to multiple messages. I know I can get it to run, just have to stop the leaks and then maybe I can get to a local meet up/cruise in and get some sage advice.
For now, I'll work with what I have and try to contact the vendors directly to make sure I'm getting what I think I'm getting.

Re: Carburetor leaking
 

Thanks. The float valve that came in the carb when I got the car was a viton tip and I got more leakage with that valve than an all metal replacement. I'm giving it another go tomorrow with a new float and new shut off valve, so hopefully that does the trick.

Re: Carburetor leaking
 

Disappointed you were not able to work with a local club. Just haven't met the right people yet. Avoid the grosejet valve, in my experience it can stick shut., and dirty fuel will give you fits.

Re: Carburetor leaking
 

I found that some of the viton-tipped float valves were sticking and not always opening so I I went back to original type or the ball type.

Re: Carburetor leaking
 

If you would post your general location then maybe someone here may be close to you. Maybe the contact you are trying to reach out to may not be getting the message for some reason. I don't believe the local (or regional club) wouldn't welcome a new member...


TOB