Ever have your engine die at a stop light?

[DannL]

After months of hard work I thought I had things tuned up perty good. Then yesterday came along. Went to Wallymart and filled the car with groceries. I felt so confident nothing would happen, I bought everything on the wife's shopping list. Even the eggs. Drove around the parking lot to get to the "easy" exit, stopped at the stop sign and waited about a minute for a break in traffic. Then the engine simply died. No sputtering. No coughing. Taken by surprise by the event I uttered that famous line . . . "Oh Crap!". Started the engine and 5 seconds later it died again. The combination of words that followed would have made Shakespeare proud of me. After the second start everything appeared normal and l continued on my way. Of course the smile that once adorned my mug was gone. So, has anything like this happened to you?

[WHN]

Something simple!

I would wait and see if it happens again.

You might want to check vent in gas cap. Enjoy.

[DannL]

Didn't know about the vent hole. I can see it now. It was fine though. Thanks.

[duke36]

Sometimes hot weather can cause a lot of issues, as expressed in other threads. Gas line not sloping downward to carb to help prevent vapor lock, failing coil or condenser, debris in gas plugging carb filter or filter in gas tank, etc.

[Jemelton#]

It Usually Happens to me when I forget to turn the gas back on!

[jm29henry]

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Float maybe set to high floods gas over the jets as the gas rushes forward its a easy fix please let us know how you make out.

[DannL]

Originally Posted by jm29henry

Float maybe set to high floods gas over the jets as the gas rushes forward its a easy fix please let us know how you make out.

That's a very good possibility. Another problem I am experiencing right now is that after I shut the car off fuel does leak out of the intake some. Which is something I read elsewhere as being a symptom of a float level problem.

[Patrick L.]

Did it just simply die while idling or when you stepped on the throttle ?

Either way for now, I'd recommend re-adjusting/checking the idle mixture.

Generally if the float is too high the engine will quit while coming to a stop. A vent issue usually raises its ugly head while cruising. But, its an 'A' so about anything is possible.

[Ernie Vitucci]

Good Morning...Since it self corrected, you might have had a couple of air bubbles in your fuel line...sort of the beginning of fuel boiling or some such. What I have found is that when I come up to a stop my right fingers are always on the hand throttle and I usually increase the RPM just a bit as I take the car out of gear and coast up to a stop. Once all stopped, I ease the throttle lever up to the stop again. I've had 'A's since the 1960's and old timers then, used to tell me it was from fuel sloshing in the carburetor bowl! They taught me the sequence of coasting up to a stop or a light and adding a bit of hand throttle. It has served me well. Have a great Model A Day! Ernie in Arizona

[30 Closed Cab PU]

Originally Posted by DannL

That's a very good possibility. Another problem I am experiencing right now is that after I shut the car off fuel does leak out of the intake some. Which is something I read elsewhere as being a symptom of a float level problem.

If you shut the gas valve off, and it eventually stops leaking, the shutoff is good and possibly your; float valve is bad, or float is bad, sometimes the float valve wears a spot into the mating area of the float which causes the float valve to not seat correctly, and a few other possibilities.

If it is leaking and teh engine is warm/sitting, you are getting a pretty rich gas mixture the 1st minutes of the car running, might contribute to the stalling.

If it continues to leak with the gas valve off, both your gas valve and carb have issues.

Fix the carb, might solve the stalling.

[100IH]

Float too high sometimes, Slosh makes a flood situation. Float level too low, goes so lean it dies. Try both.

[DannL]

Well, dismantled the carburetor which is a Xenith 2, a recent rebuild and the height of the float from the carburetor it said it 5/8 of an inch. Cleaned all the jets. The fuel leak is a slow dripping only occurs after you shut the car off and last a minute or so. This is the exact same problem I experienced with my tillison carburetor before I replaced it. I very well may add a shim under the bowl to lower it a tad in the future, should this become a serious problem.

[30 Closed Cab PU]

Originally Posted by DannL

Well, dismantled the carburetor which is a Xenith 2, a recent rebuild and the height of the float from the carburetor it said it 5/8 of an inch. Cleaned all the jets. The fuel leak is a slow dripping only occurs after you shut the car off and last a minute or so. This is the exact same problem I experienced with my tillison carburetor before I replaced it. I very well may add a shim under the bowl to lower it a tad in the future, should this become a serious problem.

If you leaving the shutoff on, does it continue to drip?

[DannL]

Originally Posted by 30 Closed Cab PU

If you leaving the shutoff on, does it continue to drip?

I've never left the shut off on.Will have to try it. I am curious.

[DannL]

Having just gone out for a small trip to get the engine nice and hot, when I came back it didn't leak. That is odd. But having just opened the carburetor, and cleaning her out completely, maybe something changed. I'm sure the dripping will rear its ugly head again here, very shortly.

[DannL]

Turned on the shut-off valve and let her set for quite a while. She's not leaking. Ran my pinky finger up the air intake to the first jet. My finger came out dry. I may need to take her on a longer drive.

[DannL]

Originally Posted by Ernie Vitucci

Good Morning...Since it self corrected, you might have had a couple of air bubbles in your fuel line...sort of the beginning of fuel boiling or some such. What I have found is that when I come up to a stop my right fingers are always on the hand throttle and I usually increase the RPM just a bit as I take the car out of gear and coast up to a stop. Once all stopped, I ease the throttle lever up to the stop again. I've had 'A's since the 1960's and old timers then, used to tell me it was from fuel sloshing in the carburetor bowl! They taught me the sequence of coasting up to a stop or a light and adding a bit of hand throttle. It has served me well. Have a great Model A Day! Ernie in Arizona

I generally I try to do this also. Yesterday though, I am perty sure I didn't. Practice. I need more practice.

[Railcarmover]

Among the many improvements Ford made with the model B engine a new carb with a side mounted float was used..no effect from starting or stopping quickly,no touchy float adjustment,the float mounted port and starboard as opposed to the A's fore and aft design.

[30 Closed Cab PU]

Could have been something as simple as something in the float valve, disassembling/cleaning may have fixed it.

[Penthode]

There are three air-fuel circuits in the Zenith: one for low speed, one high speed and one for idle. The idle circuit is most critical when stopping for if the air-fuel passage is restricted or the idle not properly adjusted, the engine will die when pulling up to a stop.

[DannL]

You people are awesome. I love it. I've been a member on a number of forums, but never one quite like this. Information here flows like water from a spring.

Coming to a stop and the inherent problems with these carburators might be what I have experienced. I guess that's all the more reason to have the rpms up a little bit when I come to a stop, as was suggested.

The paper filter that I am using very well may be too restrictive. Don't know. So I've ordered a wire filter. I'd like to keep at least the little rocks and grit from getting sucked up into the head.

[Jacksonlll]

Nex time you have the carb off, run a big file across the two mating mounting flanges. File until all is flat on both the carb and the intake flange. A tiny leak here can cause your prob and this is easy to do. 100% of the flanges must be shiny. Good luck.

[30 Closed Cab PU]

Originally Posted by Jacksonlll

Nex time you have the carb off, run a big file across the two mating mounting flanges. File until all is flat on both the carb and the intake flange. A tiny leak here can cause your prob and this is easy to do. 100% of the flanges must be shiny. Good luck.

IMO


Stalling at stop is not an inherent issue, but is a common issue that can be frustrating to solve, there are many causes. Adjusting the idle lever for stopping is a way to live with the problem.
The problem can be both electrical, or fuel system.
If the issue returns and you want further help, post on this string again.
Before you make up your mind about air filter, use the Search filter on Filter and or Air Filter. The subject has been extensively discussed before. Then decide. It is one of those subjects like "what is the best Oil" A lot of strong opinions.

[TerryH]

Years ago, I spent the money and bought a properly re-built and tested Zenith carb, and have never had any issues with it....never has stalled coming to a stop, doesn’t leak gas either, even with the fuel line left open.....

[DannL]

Originally Posted by TerryH

Years ago, I spent the money and bought a properly re-built and tested Zenith carb, and have never had any issues with it....never has stalled coming to a stop, doesn’t leak gas either, even with the fuel line left open.....

That's what I hoped fot when I replaced my old tillison with this rebuilt Zenith 2 last month. The tillison leaked just like this Zenith. I suspect 90% of folks don't inspect their carburtaors after they shut the car down for the day. With both of my carbutators the dripping doesn't start until a minute or two after the car is shut off. I suspect that's when the air stops moving and the heat builds up in the carb. Tested the heat theory scientifically with my hand by touching the carb when the car is running and then several minutes after shutdown. The carb is just a big heatsink on the manifold.

[30 Closed Cab PU]

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Heat build up is normal when you shut off any motor, including the carb heating up, but this should not cause the carb to leak. More than likely what happened is while running, gas usage kept the float in the correct position, and when turned off a very slow leak in the carb overfilled the float bowl which took a couple of minutes. Typical causes are; a float valve that does not seat properly, a bad float, a float valve that does not properly seal/seat in its threads, too high of a float setting, a sticking float, etc.


So are you just wanting additional info, or has the problem reappeared?

[DannL]

I think this rebuilt carburetor has a problem also. This morning went out and found a drop of fuel hanging from the bottom bolt on the carburetor followed this back to the intake and all the way up to the Jets. So as suggested the float valve is probably not holding back the fuel. Will check that and probably replace the fuel shut-off petcock for grins. Definitely not lacking in info here. You all have helped tremendously.

[30 Closed Cab PU]

Without rereading the string again, do not know if it was mentioned. Shim Washers on the float valve sometimes seep. A secondary function of them is sealing the float valve.


What I have found is the shiny shims can be a problem, the red shims seem to work the best. You may not be able to get the exact float level with them that you want, better that the float level using the gauge is slightly lower than higher.


Do not use any type of sealer, it only masks the real issue. Sealer (Teflon tape/dope, thread lock, etc.), can break up/dissolve and plug passages and jets. And if you need to take it apart again, sealer can break off/apart and get into the carb.


A secondary method not using the float gauge is to hold the upper part of the carb body upside down so the float seals the float valve. The solder line of the float should be parallel to the surface of where the float bowl would seat to the upper body. Or if you want to use a different setting, take what you have and measure at the float free end solder line and adjust your shims for that measurement. This way you can get close enough without having to repeatedly take the carb on and off the motor like when using a float gauge.


A quick check is to hold the carb upside down and blow into the carb gas inlet hole, exercise the float up and down and see if it seals. The weight of the float gently seating should seal. This may not tell you if you have a seepage issue.


If you have a hand vacuum pump/gauge you can do a better test by leaving vacuum on the gas inlet with the carb upside down. It should hold for a long time. You also can pretest the valve before putting it in the carb. The pumps are inexpensive, the one I got from harbor freight works good.


I and other have had issues with bad fuel shutoffs out of box new. I now buy them from Brattons. They are USA made, 3 year Warranty. I have also heard that Snyders are good, but do not have experience with them.


One of the issues is rust/grit in the gas tank getting into the shutoff, and gouging the seat/ball of the shutoff. I and others run a pencil filter on the inlet to the shutoff to prevent this from happening. It sticks up into the gas tank


https://www.brattons.com/fuel-tank-filter-screen.html