Fuel Fumes From Gas Tank

madmike · Post by **madmike** » Mon Jan 06, 2014 11:09 am

After restoring the M38A1 and filling the gas tank, I notice a lot of gas fumes from sitting overnight in a pretty air tight garage. No gas leaking from anywhere and when I walk by the filler cap, the smell is stronger. How much should these tanks leak vapors? I have a new gasket on the cap but since these are open to the atmosphere caps under normal running condition, should I turn the cap to closed when storing in the garage? Would it make a difference?

I have my 56 Willys wagon in there too and between the two of them, I am beginning to worry about the garage winding up in another zip code.

Mike

Post by **wesk** » Mon Jan 06, 2014 11:17 am

Modern unleaded gas stinks period. The same quantity of gas kept in the same tanks if it were early leaded gas would not smell so strong. Some caps are sealed and have a built in relief valve that pops around 2 PSI differential. These will not emit such a strong smell. Your A1 with the standard GI fording cap in the open position is venting 100% all the time and if you have the 54 & up vent system with only the small vent valve setting on top of the tank wiithout the tube running to the air cleaner this smell gets worse. What you could do is install a modern auto charcoal cannister and plumb a vent line from the fitting on the tank to the cannister and close the fording cap valve.

Bretto · Post by **Bretto** » Mon Jan 06, 2014 11:32 am

Any possible tiny small leaks in the tank that may be just seeping out from underneath the tank and the tub that may be small enough to never drip?

madmike · Post by **madmike** » Sun Jan 12, 2014 7:34 pm

I checked and no leaks. I like the idea Wes posted but I will have to investigate further to get measurements for the proper size charcoal filter to fit somewhere on the body, preferably out of sight. If I recall, the charcoal canisters are rather large but there may be smaller ones for smaller cars. Thanks for the info to both of you.

Mike