[PontiacHO]

What do y’all do about strong gas fumes in the garage after driving on hot days? My garage has a gas water heater and I’m concerned about the fumes my Firebird emits into the garage. Quick fix is to leave the car out until it cools some and has less fumes… Considering drilling a small hole in the gas cap so fumes can escape easier while driving and not be as built up. I can loosen the gas cap after a run and there’s definitely some pressure building in the tank.

[steve25]

It may be coming from your Carb, because today’s fuel boils off at 150F if I am not mistaken.

[tempest1964]

I leave the overhead garage door open until car cools to ventilate fumes.

[Rachelsdad]

If the smell of raw gas is stronger than you might expect, after you get the engine hot, remove the air cleaner and check around the carb and the lines for leaks. Another thought is that something could be amiss with your vapor return line or even your gas cap (though the cap would allow vapur to escape even when the engine is/was cold, so the engine compartment is the first most likely suspect.

Other than that, yep, leave the door open until it cools down a bit. Best I can suggest OTTOMH.

GL

[SRGN]

If you haven't done so already, replace the rubber fuel hoses with new, ethanol compatible lines. The liquid fuel may not be leaking yet, but old lines will allow vapors to pass through. My 62 can be parked hot in the garage and have zero gasoline smells inside.

[Dragncar]

Just be glad water heaters have to be raised up off the floor where the fumes are. Gas fumes are heavier than air.

[PontiacHO]

Originally Posted by steve25

It may be coming from your Carb, because today’s fuel boils off at 150F if I am not mistaken.

That’s my thought also. I find it odd that this car (68 Firebird) has no tank ventilation setup at all. The cap is “Vented” but if I’m not mistaken that’s to allow air in, not fumes-pressure out. I recently added a fuel pump return line that was original to air condition equipped cars to keep the fuel cooler. Only using non ethanol fuel. My carb is a 1977 Quadrajet with the large 1/2 bowl vent that is venting to inside the air breather. There’s always pressure on the gas cap after running so I’m wondering if that pressure is pushing fuel past the needle and seat and creating the fumes after a run???
Anyway I’m going to drill a hole in the fuel cap to hopefully relieve the pressure and see what happens. I’ll never fill the tank full anyway so any fuel sloshing will be minimal. I only allow one spirited run on each outing so no worries about fuel escaping while driving. This car fights me every turn… It just does not like hot weather…

[chiphead]

Does a FB not have a vented tank neck? My '67 GTO has a vent in the neck. But yes, I get the same smell in the garage after a run. I assume it's the fuel evaporating from the carb. The bowls will be almost empty a day or 2 later after a run, and I've checked for leaks.

The wife has actually asked if the house is going to explode, we have a gas water heater too.

I leave the door open after I park it, to vent the smell and the engine heat.

[MPKind]

Dealing with the same. Tank vent hose was cracked so it made it really bad while driving. Fixed. Still stinks tho. Prolly a carb issue but it worked great last year. It never ends.