Occasionally starved for fuel

Pat Martone

Pat Martone

Senior Member
I welcome advice in solving my intermittent fuel starvation problem.
My car occasionally "dies" while cruising, whereby I coast off to the side of the road and inspect. Confirming that I have spark, I get back in the car and it typically starts and I drive off. This intermittent problem has plagued me for a couple of years and I would like to solve it, but can't find the smoking gun. My engine dies about 2-3 times per year, but it died twice yesterday, so now I am more concerned - on both occasions I was able to safely coast off to the side of the road, whereby I the car started again and I drove off.
While I've been told that most fuel problems are really electrical, I am convinced I have a fuel problem because of how the engine dies; coughing/sputtering before dying - and I am always able to confirm that I have spark after I pull over and inspect.
-My gas tank is clean and clear, my carburetor was professionally rebuilt about 4 years ago, and it is currently clean inside.
-I don't think I've got a vapor lock problem, as it occurs when outside temps are between 40 and 80 degrees, and it seems to happen when cruising along at low speeds in 3rd gear at around 25-35 mph.
My next step is to wait for the arrival of a rebuilt carburetor from Bert's to determine if I have a carburetor problem.
Thanks in advance for your advice!
 
if it is fuel most likely would be the float valve sticking shut or the fuel line pushed in to far at the carb or sediment. i am sure you tried loosening the gas cap already.

to see if it is a spark situation, i would drive it with an inline spark tester to monitor when the issue happens.. i rig up a long plug wire to extend past the hood then back to the cap
 
Last edited:
I remember a guy that had this same issue. Finally after removing the fuel shut off under the tank a round foil disk was found in the bottom of the tank. It was probably a foil seal off from a bottle of HEET that fell in. It was acting like a flapper valve on the fuel intake on occasion.
 
If you don't have the shutoff valve filter yet, be sure to install one.

I've often thought about doing just what Mitch said by running a long coil wire outside the hood to an inline spark tester and then back to the distributor. This is the very best way to check for ignition problems.

Do you have tank liner that might be coming off?
I'm dealing with that problem right now on my 1950 Studebaker. Some of the liner was plugging the tank pickup line, so yesterday I mechanically removed all the liner by tumbling the tank strapped to my cement mixer and filled with a few pounds of lag bolts.
 
Thanks for all of you inputs/thoughts so far.
My tank is very clean, rust free, and not lined with anything that I can tell.
I'm hoping a carburetor swap-out might further help me to isolate the problem.
 
Did this happen after you had just made a stop, or had you been cruising along for several miles and it just sputters and dies out of the blue?
 
Does the engine speed up a little just before it cuts off ??? Sign of lean out when fuel is cut ., You guys that cut your fuel valve when you park can attest to that ,.,.
Change the carb will eliminate it .,,

,.
.,
 
I cannot find a pattern to how/why it dies, and it seems to only happen a couple of times per year, but yesterday it happened twice. It seems to die when I am cruising at around 25-40mph, on straight and level terrain.
 
It could be as simple as having a radiator cap on your gas tank instead of a gas cap.
The gas caps are vented and the radiator caps are not.
Do you hear a SWOOSH when you take off the gas cap ? If so, that is the vacuum escaping, which held the gas back.
MIKE :) (mikeburch)
 
A. That which is "seen" can sometimes cause a big mental block.

B. That which is "unseen" most likely "is" always where the problem lies.

C. You have "seen" 50% of the "clean" inside of the tank ..... but not where it counts, at the tank drain and cut off valve ...... ever drain a bath tub that "looks" perfectly clean, but never checked the ("????") at the drain that causes intermittent slow draining? Possibility no. 1.

D. Do one at a time and "think" ..... it is all very mental.

E. Have you removed your carburetor and very gently rotated it back and forth to carefully listen for that almost silent "click" to verify that your float is not sticking?
Possibility no. 2.

F. Above replies are numerous great possibilities to check one at a time ....... forget about the clean tank ...... something is else happening ....... if the tank were a perfectly clean toilet bowl and the combustion chamber were a septic tank, the liquid in the toilet bowl has to flow "constantly" to the septic tank for the car to run.

The problem will always be found with the last thing you check ...... because after finding the problem, you quit looking.

Sincerely hope this helps.
 
I have had it happen to me, also. My first reaction is to give the choke a quick pull and release, in gear, while its still coasting....sometimes this helps, most times not.
Good Luck:)
 
Last edited:
Hi Pat,

Checking spark right after the car stops is a great start.

If it is a fuel problem, intermittent problems are best solved when the problem occurs.

How can you "verify" if it "is" a fuel problem immediately after it quits?

1. Maybe immediately disconnect fuel line at carburetor to check gas flow from tank to carburetor?

2. Next time, maybe immediately try starting while choke is pulled, then if it does not start, immediately check to see if plugs are wet with fuel?

3. When it begins to kill, open GAV and/or pull out choke?

4. One test at a time.

There are several possibilities to check like this ... get back and report what you find.
 
Interesting that the subject of the fuel line pushed too far into the carb has and is mentioned all the time, yet you haven't mentioned that you checked that.

I had a very similar problem to what you are experiencing and essentially (and this can be a stuck float also) where the car dies because the carb bowl is empty. In a few moments, it is full again.

In my case, the fuel line ferrule was about 3/8" from the end of the fuel line,a and the screen inside the carb was crushed. If you find this, cut the line shorter (about 1/8" from the ferrule) and install but also remove that brass end plug and make sure the screen inside is not crushed.

I have heard that the ferrule on fuel tank (strainer) end also can cause this starvation problem.

Good luck,

JackD
 
Thanks for all of the informative replies!
My fuel line is not pushed in too far, because I can easily remove the carb screen filter and it is not crushed and is perfectly clean and clear.
My next step is to try a different carb, which I ordered (rebuilt) from Bert's which should arrive in 2-3 weeks. I am hoping it is a carb (float?) problem and not a fuel tank problem! Carb problem is much easier to fix than a tank problem!
 
Its always good to have a spare carburetor, but if it runs right most of the time, with only an occasional hiccup, there cant be too much wrong with the one you have.
 
:rolleyes:MMMM sorry if I did not pick it up in the thread but have you done as Mike (#9) suggested. Sounds to me like rust has slowly been building in the inner wall of your gas cap. When the cars dies it will take 10-20 minutes and then it starts. That time span is what it takes for the air to travel back into the tank. As Mike mentioned when it dies the first thing is SLOWLY remove the gas cap and listen for the swoosh. Carefully blow the cap with an air nozzle. Rust particles will fly all over hell. Don't ask me how I know.
 
Nope, but thanks for the suggestion; I don't use an inline fuel filter. I am hoping it is a sticky float, even though I studied it and it looks Ok.
 
i always try to preach a diagnosis before shot gunning. with intermittent problems you need to catch it as its happening.. as mentioned in my other post is one way to ck for int spark. another thing that can be tried for a fuel issue is as soon as she quits turn off the fuel valve inside. then open the fuel bowl drain plug and meter what comes out in a calibrated cup...compare this reading to what your bowl would normally hold when its running good
doing the test this way will not give the fuel enouigh time to refill the bowl by the time you pull over get out and open the hood.
 
Rex_A_Lott said:
I have had it happen to me, also. My first reaction is to give the choke a quick pull and release, in gear, while its still coasting....sometimes this helps, most times not.
Good Luck:)
Click to expand...

That's a good way to check for fuel related. Also do what Mitch just said, close the valve right away and check the fuel bowl.

If you suspect it might be a distributor problem, move the spark lever up and down and see if it runs ok. This would indicate a problem inside the distributor, and most like the lower plate wire shorting out or broken.

The check the ignition switch (and anyone can do this any time, even if the car runs great) start the engine, then slowly turn the key to the off position. If the engine quits when the key is barely turned, the switch is bad. This happened to me, and I had to take the switch apart and improve the contacts. It wasn't an easy job to improve a poor design, but it's getting me by until I install the original popout.
 
You must log in or register to reply here.
Back
Top