The Ford Barn

CaliforniaBorn36 · 12-04-2022, 09:12 PM

Stopped to fill up my 1936 today and after I was done and had removed to pump nozzle, gas began flowing up out of the filler neck and down the fender. It was almost like something was causing pressure in the tank.

1.) I did not top off the tank. Stopped when the nozzle clicked first time.
2.) Engine was running.
3.) Engine temp was only about 150 degrees.
4. Weather was cool, mid 50s
5.) At least a cup, probably much more, flowed up and out the filler neck.
6.) This all happened while sitting at the gas station, so cars resting angle did not change.

What would cause this. I have had the car for over 12 years and this is the first time this has ever happened.

ford38v8 · 12-04-2022, 11:57 PM

Faulty internal venting, I believe. Having been a motorcycle rider in my younger days, I learned to never trust the automatic shutoff, and to always hold the filler so as to allow the filler to breath on its own rather than to rely on the back-suction. I know that you, as a Californian, must also dislike that system, and some others in less environment controlled areas may not know what I'm talking about!

19Fordy · 12-05-2022, 10:34 AM

The vent is not able to handle (vent) the back pressure being created by the volume of gas being fed into the tank by the nozzle.

tubman · 12-05-2022, 10:39 AM

This was an ongoing problem with my old '36 3-window. One (albeit a minor one) of the reasons I sold the car.

Bill OH · 12-05-2022, 11:57 AM

I have to hold the nozzle discharge vertical and run the gas in slow to prevent the blow back - the vent by Ford is not adequate. Requires patience. I gas mine twice a year, otherwise I would install a larger vent.

Lawson Cox · 12-05-2022, 01:27 PM

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First off, never put gas in the tank while the engine is running. It's a matter of safety.

If this is the first time this has happened, no worries, just keep an eye out for it in the future. Back pressure for some reason. It is probably just a quirk. My 2 ¢

Kube · 12-05-2022, 01:52 PM

Quote:

Originally Posted by ford38v8

Faulty internal venting, I believe. Having been a motorcycle rider in my younger days, I learned to never trust the automatic shutoff, and to always hold the filler so as to allow the filler to breath on its own rather than to rely on the back-suction. I know that you, as a Californian, must also dislike that system, and some others in less environment controlled areas may not know what I'm talking about!

And I'd learned to shut the engine off. Kinda like the big WARNING sign on every pump.

Flathead Fever · 12-05-2022, 06:56 PM

You have to remember that the original gas station pump nozzles did not have a boot to seal the neck. The neck could vent while the tank was filling up. The modem vehicles tanks have filler necks that have check balls to prevent back flow in the event of a roll over. That check ball might also close as the tank gets full and prevent overfilling. The excess pressure activates the gas pumps auto shutoff to prevent overfilling. The gas station pump also has a vapor recovery system that helps vent the tank while its filling.

DavidG · 12-05-2022, 06:58 PM

The question comes from California, where you can bet the store that pumping gas with the engine running is an unlawful act.

Kube · 12-05-2022, 07:01 PM

Quote:

Originally Posted by DavidG

The question comes from California, where you can bet the store that pumping gas with the engine running is an unlawful act.

And ignorant.

Flathead Fever · 12-05-2022, 08:32 PM

Quote:

Originally Posted by DavidG

The question comes from California, where you can bet the store that pumping gas with the engine running is an unlawful act.

I'm in CA too. I'm just happy we can still get gas here for now. Please don't think we are all nuts here. It's about 50/50. If you stay away from the big cities, it's still a nice place to live. It's always been illegal here to fill up with your engine running. 30 years ago, I had a job that required me to insect the pumps to make sure that warning decals were on the pumps.

Mart · 12-06-2022, 08:25 AM

...

GB SISSON · 12-06-2022, 01:35 PM

Quote:

Originally Posted by Mart

...

Thanks Mart, I needed that this morning.

CaliforniaBorn36 · 12-06-2022, 07:36 PM

To clarify, engine was running, after filling had been completed, not while filling. Yes, that would be dangerous and illegal.

The reason I mentioned engine running was to clarify that some gas should have been being drawn by the engine and creating less back pressure.

While I may not have been totally clear, Thanks to all who offered useful thoughts.

Others might try a little kindness so as not to run people off of this site.

VeryTangled · 12-06-2022, 11:41 PM

I have a 35 and a 36 and both require very slow filling and careful monitoring while fueling. I don't go over 3/4 of a tank or I get spilling onto the fender while turning right no matter the fuel cap gasket condition (with my LHD cars). I stop for fuel frequently because of this. I've also seen spill over on sunny hot show fields when the fuel tank had been recently topped up. Sad to see on shiny vehicles!

al's28/33 · 12-07-2022, 12:41 AM

My '33 pickup spills over all the time when I top it off. And on really hot days it just seeps out after every fill-er-up. Peeled off the paint from the rear fender but I am certain all the extra patina will increase her value!

Jeff/Illinois · 12-07-2022, 03:04 PM

CaliforniaBorn... we have the same issue with our '36 Ford Pickup.

To fix that I only fill it up to about 3/4ths anymore! That seems to work for me anyway! We are running the original fuel gauge and it is very accurate actually. I look into the tank thru the filler opening and when I see the level approaching the bottom of the filler tube I call it done!

Good luck.

12-04-2022, 09:12 PM	#1
CaliforniaBorn36 Senior Member Join Date: Oct 2012 Location: San Francisco Bay Area Posts: 427	Gas flowing out of the Filler Neck after Filling up? Stopped to fill up my 1936 today and after I was done and had removed to pump nozzle, gas began flowing up out of the filler neck and down the fender. It was almost like something was causing pressure in the tank. 1.) I did not top off the tank. Stopped when the nozzle clicked first time. 2.) Engine was running. 3.) Engine temp was only about 150 degrees. 4. Weather was cool, mid 50s 5.) At least a cup, probably much more, flowed up and out the filler neck. 6.) This all happened while sitting at the gas station, so cars resting angle did not change. What would cause this. I have had the car for over 12 years and this is the first time this has ever happened.

12-04-2022, 11:57 PM	#2
ford38v8 Senior Member Join Date: Jul 2011 Location: SF Bay Area Posts: 6,645	Re: Gas flowing out of the Filler Neck after Filling up? Faulty internal venting, I believe. Having been a motorcycle rider in my younger days, I learned to never trust the automatic shutoff, and to always hold the filler so as to allow the filler to breath on its own rather than to rely on the back-suction. I know that you, as a Californian, must also dislike that system, and some others in less environment controlled areas may not know what I'm talking about! __________________ Alan

12-05-2022, 10:34 AM	#3
19Fordy Senior Member Join Date: May 2010 Location: Coral Springs FL Posts: 10,949	Re: Gas flowing out of the Filler Neck after Filling up? The vent is not able to handle (vent) the back pressure being created by the volume of gas being fed into the tank by the nozzle.

12-05-2022, 10:39 AM	#4
tubman Senior Member Join Date: Dec 2013 Location: Minnesota, Florida Keys Posts: 10,319	Re: Gas flowing out of the Filler Neck after Filling up? This was an ongoing problem with my old '36 3-window. One (albeit a minor one) of the reasons I sold the car.

12-05-2022, 11:57 AM	#5
Bill OH Senior Member Join Date: May 2010 Posts: 426	Re: Gas flowing out of the Filler Neck after Filling up? I have to hold the nozzle discharge vertical and run the gas in slow to prevent the blow back - the vent by Ford is not adequate. Requires patience. I gas mine twice a year, otherwise I would install a larger vent.

12-05-2022, 01:27 PM	#6
Lawson Cox Senior Member Join Date: May 2010 Location: Above the gnat line in Georgia Posts: 7,009	Re: Gas flowing out of the Filler Neck after Filling up? Sponsored Links (Register now to hide all advertisements) First off, never put gas in the tank while the engine is running. It's a matter of safety. If this is the first time this has happened, no worries, just keep an eye out for it in the future. Back pressure for some reason. It is probably just a quirk. My 2 ¢ __________________ Life is like a roll of toilet paper. The closer to the end, the faster it goes. It is better to be seen, than viewed. "We sleep safe in our beds because rough men stand ready in the night to visit violence on those who would do us harm".

12-05-2022, 06:56 PM	#8
Flathead Fever Senior Member Join Date: May 2010 Location: Yucaipa, CA Posts: 1,095	Re: Gas flowing out of the Filler Neck after Filling up? You have to remember that the original gas station pump nozzles did not have a boot to seal the neck. The neck could vent while the tank was filling up. The modem vehicles tanks have filler necks that have check balls to prevent back flow in the event of a roll over. That check ball might also close as the tank gets full and prevent overfilling. The excess pressure activates the gas pumps auto shutoff to prevent overfilling. The gas station pump also has a vapor recovery system that helps vent the tank while its filling.

12-05-2022, 06:58 PM	#9
DavidG Senior Member Join Date: May 2010 Location: southeastern Michigan Posts: 10,101	Re: Gas flowing out of the Filler Neck after Filling up? The question comes from California, where you can bet the store that pumping gas with the engine running is an unlawful act.

12-06-2022, 07:36 PM	#14
CaliforniaBorn36 Senior Member Join Date: Oct 2012 Location: San Francisco Bay Area Posts: 427	Re: Gas flowing out of the Filler Neck after Filling up? To clarify, engine was running, after filling had been completed, not while filling. Yes, that would be dangerous and illegal. The reason I mentioned engine running was to clarify that some gas should have been being drawn by the engine and creating less back pressure. While I may not have been totally clear, Thanks to all who offered useful thoughts. Others might try a little kindness so as not to run people off of this site.

12-06-2022, 11:41 PM	#15
VeryTangled Senior Member Join Date: May 2010 Location: (Not far enough...) Outside of DC Posts: 3,387	Re: Gas flowing out of the Filler Neck after Filling up? I have a 35 and a 36 and both require very slow filling and careful monitoring while fueling. I don't go over 3/4 of a tank or I get spilling onto the fender while turning right no matter the fuel cap gasket condition (with my LHD cars). I stop for fuel frequently because of this. I've also seen spill over on sunny hot show fields when the fuel tank had been recently topped up. Sad to see on shiny vehicles! __________________ -Jeff H Have you thought about supporting the Early Ford V-8 Foundation Museum? Last edited by VeryTangled; 12-06-2022 at 11:47 PM.

12-07-2022, 12:41 AM	#16
al's28/33 Senior Member Join Date: Jun 2010 Location: Redwood City, CA Posts: 1,591	Re: Gas flowing out of the Filler Neck after Filling up? My '33 pickup spills over all the time when I top it off. And on really hot days it just seeps out after every fill-er-up. Peeled off the paint from the rear fender but I am certain all the extra patina will increase her value! __________________ 1928 "A" Phaeton (mid year with many early features) 1933 "V8" Closed-Cab Pickup Truck (originally a Model B, 4 Cylinder dating to May, 1933)

12-07-2022, 03:04 PM	#17
Jeff/Illinois Senior Member Join Date: May 2010 Posts: 2,789	Re: Gas flowing out of the Filler Neck after Filling up? CaliforniaBorn... we have the same issue with our '36 Ford Pickup. To fix that I only fill it up to about 3/4ths anymore! That seems to work for me anyway! We are running the original fuel gauge and it is very accurate actually. I look into the tank thru the filler opening and when I see the level approaching the bottom of the filler tube I call it done! Good luck.