Simple Reason to Function Check a Vented Gas Cap

[DentsideDepot]

Now Im worried cheap auto parts or the Covids will pop out of my driveway

[blaydCA]

The truck just considers that driveway it's home.
It's just MARKING IT'S TERRITORY!
You should be HONORED!

[gaborbata]

That is some valuable lesson right there. Thanks for posting.
And not just for releasing the pressure. Once we were going crazy chasing an intermittent fault on a garden tractor for weeks, the engine just stalled from time to time for no reason. The cap didn't let air into the tank to equalize the pressure, so the fuel wouldn't flow because of the vacuum in the tank.

[cheyeneharding]

Yo that thing is CLEAN underneath. Good job my man.

[Bloodbain]

I found out the hard way that tanks with vent tubes do the same thing, especially if filled with diesel. Also if your vent tube, or vented cap, if you have one, is clogged, your engine will stall after running a short while, due to a vacuum forming in the tank.

When my truck had a gas engine in it, i could fill up both tanks, park it in the driveway and it would never overflow out the vent tubes even on the hottest days. Flash foward a few years, the same truck now has a diesel engine. I filled up both tanks early in the morning (cool temps). The day heated up and several gallons of diesel got dumped all over the driveway out of the vent tubes. Only thing I can figure is diesel expands in volume more than gasoline does as it warms up.

Side note. If anyone reading this converts their old squarebody truck to diesel, change your sending units to the diesel style. The only difference is this: the return port on the gas style sending unit ends at the very top of the fuel tank, letting the returned fuel free-fall into the tank. The DIESEL style sending unit has a tube that goes all the way to the very bottom of the tank, so that the returned fuel is let out at the bottom and does not free-fall. Why is this important? The fuel will froth and foam up with bubbles. Once you get down to about 1/3 of a tank, you'll start pulling aerated fuel and have a noticeable drop in power. At 1/4 tank, it gets so bad you can barely move down the road at all. Diesel injection systems do NOT like aerated fuel.

It took me a WHILE to figure that one out.

[DownHillgamer]

Straight to the wuhon covid lab, right next door to the factory where the kids made that vented cap lol

[Qwaxyducky]

Dude just flexed how clean his truck was like that

[Organized_Thoughts]

"Expecially" gives me the same feeling as "lemme axe you a question"

[kalybnielsen]

Was just called to help on a 52 Ford F2 that wouldn't start, by the time I fixed the no spark issue (if people say they know what they're doing and they've already checked things like the condition of the points, check them anyway), after it started and had what looked like oil leaking from the front of the engine which turned out to be oil and fuel, about 5 gallons worth from the gas being pushed through the tank, through the added electric fuel pump, through the carburetor and into the engine past the valves and piston rings. All from a non vented gas cap

[halseyknox]

Good advise ...kinda of already knew that but your experience solidifies my thoughts

[TheDeafMechanic]

I remember at Holley ford fest a few years ago a poor guy with a 67 F-250 had his paint ruined when gas was pushed back out and ran down the cab. Bubbled it like crazy unfortunately

[EUREKA]

Good advice! Not to mention a possibility of an explosion 😢

[andrewbauer]

You can remove the valve easy peasy. Pry on the two small tabs with screw driver. Now it vents both directions unrestricted.

[darth--chungus]

Always make sure you have a vented cap on a fuel system that needs one, as well.

Had a customer come in to work on his First Gen Bronco that he restored.. he said it was stalling and idling rough, pulled the cap and it shot fuel across the parking lot. Exhaust was ran too close to the tank and heating the fuel with no where for it to go.

[myyracommunity]

Or just put a hole into the filling tube and put a tube up into the fender so it doesnt overflow gas

[phillipthethird]

Finally, something on YouTube that I can actually use.

[KCUDX]

Fix the tank vent though so you don't get sprayed when refueling. And you don't have to worry about this, but make sure the vent lines don't leak or you end up with the problem you had, bad cap or not.

[robertfoote]

Man year of truck wouldn't look like that in the rust belt.
Now if it only had a 300 six, four speed, and the gear drive transfer case.
Nice ride, me so jealous.

[thomasdearment]

your lucy most gas tanks back in the day on a hot day would vent it anywhere you were parked also your cooling would do the same

[TheTyberZann]

Makes me glad that we have concrete and not petroleum based talcom powder.