The Ford Barn

1929 · 08-26-2018, 08:05 AM

The car would run good, then the next day there would be problems, it was a pattern like this all the time. I almost removed everything to go back to stock. Cleaned the carb, even put another carb on, no difference. Removed the FS ignition, went back to stock. Drained some fuel, no debris, and installed a new fuel line. Removed fuel pump and regulator, went back to gravity, still same results. Installed new dashboard wires,new plugs etc,etc. Had others look and try to figure it out, they were confused, until one guy said, take off the GAS CAP, which was only over 3 years old. Now the car runs great again. All this could have been avoided by just five seconds of unscrewing a GAS CAP! The inner part of the gas cap with the hole looks like it went flat to the top surface, wondering if that's where it started, or if the fuel pump created the issue to the cap.

Jim/GA · 08-26-2018, 08:30 AM

That's a very valuable lesson to learn. Thanks for sharing with us!

I had a similar experience a few years ago while on tour. One of the cars touring with us had a problem with his car running poorly at times, and it ran great other times. We were driving a lot each day and refueling pretty often. He pulled over once right after refueling at an Exxon station and he was out of his car, ranting and raving about how that Exxon gas was bad, causing the problem. Everyone else's car was running fine on it.

One of the guys in the group reached out and loosened the gas cap 1/4 turn (it was a'31 S/W Town Sedan) and said "Let's try this for a few miles". Sure enough, the car ran great for the rest of the tour if he left the gas cap loose (days of driving). When the tank was full, there was not much air in the top of the tank to expand as the gas was consumed. So the fuel would not flow to the carburetor.

BILL WILLIAMSON · 08-26-2018, 10:17 AM

This reminded me, many times when attacking a problem such as this, the filter in the top of a Zenith, is often overlooked!
Bill Pluggedup

johnbuckley · 08-26-2018, 11:28 AM

you got off lightly 1929.... I took the head off once trying to trace a running fault -- should've just taken the gas cap off!!

Tom Endy · 08-26-2018, 01:35 PM

The reproduction gas caps for the 30-31 cars are designed to fail with the single rivet in the center. Repeated twisting of the cap on and off the tank will eventually allow one of more of the three parts to rotate out of position and block off the vent hole.

Snyder's carry a better reproduction cap with two rivets.

Attached article shows how to modify the single rivet caps before they cause grief.

Tom Endy

john in illinois · 08-26-2018, 01:36 PM

Sponsored Links (Register now to hide all advertisements)

The gas cap vent was the first problem I had with my new to me A 10 years ago.
We made it about 3 miles from home on our first ride.
Good luck.
John

08-26-2018, 08:05 AM	#1
1929 Senior Member Join Date: Jan 2015 Location: New York Posts: 943	Months of confusion The car would run good, then the next day there would be problems, it was a pattern like this all the time. I almost removed everything to go back to stock. Cleaned the carb, even put another carb on, no difference. Removed the FS ignition, went back to stock. Drained some fuel, no debris, and installed a new fuel line. Removed fuel pump and regulator, went back to gravity, still same results. Installed new dashboard wires,new plugs etc,etc. Had others look and try to figure it out, they were confused, until one guy said, take off the GAS CAP, which was only over 3 years old. Now the car runs great again. All this could have been avoided by just five seconds of unscrewing a GAS CAP! The inner part of the gas cap with the hole looks like it went flat to the top surface, wondering if that's where it started, or if the fuel pump created the issue to the cap.

08-26-2018, 08:30 AM	#2
Jim/GA Senior Member Join Date: May 2010 Location: Young Harris, GA Posts: 1,821	Re: Months of confusion That's a very valuable lesson to learn. Thanks for sharing with us! I had a similar experience a few years ago while on tour. One of the cars touring with us had a problem with his car running poorly at times, and it ran great other times. We were driving a lot each day and refueling pretty often. He pulled over once right after refueling at an Exxon station and he was out of his car, ranting and raving about how that Exxon gas was bad, causing the problem. Everyone else's car was running fine on it. One of the guys in the group reached out and loosened the gas cap 1/4 turn (it was a'31 S/W Town Sedan) and said "Let's try this for a few miles". Sure enough, the car ran great for the rest of the tour if he left the gas cap loose (days of driving). When the tank was full, there was not much air in the top of the tank to expand as the gas was consumed. So the fuel would not flow to the carburetor. __________________ Jim Cannon Former MAFCA Technical Director "Have a Model A day!"

08-26-2018, 10:17 AM	#3
BILL WILLIAMSON Senior Member Join Date: Dec 2010 Location: FRESNO, CA Posts: 12,560	Re: Months of confusion This reminded me, many times when attacking a problem such as this, the filter in the top of a Zenith, is often overlooked! Bill Pluggedup __________________ "THE ASSISTANT GURU OF STUFF"

08-26-2018, 11:28 AM	#4
johnbuckley Senior Member Join Date: Jul 2010 Location: United Kingdom Posts: 1,443	Re: Months of confusion you got off lightly 1929.... I took the head off once trying to trace a running fault -- should've just taken the gas cap off!!

08-26-2018, 01:36 PM	#6
john in illinois Senior Member Join Date: May 2010 Location: Illinois Posts: 2,184	Re: Months of confusion Sponsored Links (Register now to hide all advertisements) The gas cap vent was the first problem I had with my new to me A 10 years ago. We made it about 3 miles from home on our first ride. Good luck. John