1940 Gas Tank isues

[Mid Florida Cruisers]

Hi Gear Heads,

I have a 1940 Ford pickup with original style gas tank from Mac’s. My issue is every now and then the gas expands and leaks out the gas cap usually at a car show, but never in the garage, are there ideas to remedy this?

 

[4dFord/SC]

I always try to park with the filler cap on the uphill side at summer shows.

 

[jimTN]

add a vent tube

 

[Mid Florida Cruisers]

Are you saying the original vent tube part of the filler neck my not be sufficient enough?

 

[okiedokie]

Never fill it up right before attending, always park with the filler cap on the higher side. I can still hear my Dad telling gas station attendants " don't top it off" for that very reason. The sun is the culprit as to why it does not do it in the garage.

 

[Russ/40]

Really kills the paint too. Just dont fill it. The only solution.

 

[Mid Florida Cruisers]

Thanks for the answers guys. I figured as much. I've tried 3/4 the way full and sometimes it will still do it. I thought the gas cap could have been the culprit, but sat at a car show for six hours with the cap off watching the gas run down the fender, even ran the flathead a few times for about 5 minutes ,and that bought me about 20 minutes or so until it started running out again.

 

[47Merc]

I don't know if this is applicable or not but it is something to think about.

Quite a few years back my father had a part time job as a Insurance fire investigator in a country area where a lot of the farmers park their cars under the house.

After investigating quite a few burnt down houses he found that the farmers (or their wives) had been to town in the family car and the last thing they did before going home was to top the gas tank up in so it was ready for the next trip.

As these house fires happened in winter time he found the gas in the underground tank at the gas stations was very cold when it was pumped into the car and when the car got home and parked in the warm air under the house the gas in the tank warmed up and expanded pushing some out the overflow or cap and allowing vapour to spread across the garage floor.
As with some farm houses, all these houses had an old deep freeze fridge under the house and when the freezer started automatically the spark from the electric switch ignited the vapour and exit one house, car etc.

 

[Russ/40]

I don't know if this is applicable or not but it is something to think about.

Quite a few years back my father had a part time job as a Insurance fire investigator in a country area where a lot of the farmers park their cars under the house.

After investigating quite a few burnt down houses he found that the farmers (or their wives) had been to town in the family car and the last thing they did before going home was to top the gas tank up in so it was ready for the next trip.

As these house fires happened in winter time he found the gas in the underground tank at the gas stations was very cold when it was pumped into the car and when the car got home and parked in the warm air under the house the gas in the tank warmed up and expanded pushing some out the overflow or cap and allowing vapour to spread across the garage floor.
As with some farm houses, all these houses had an old deep freeze fridge under the house and when the freezer started automatically the spark from the electric switch ignited the vapour and exit one house, car etc.

Outstanding information 47 Merc!