Fuel leak!!

I have a '96 F250, 7.5 liter 2WD, approx 190k on the odometer.
This truck has dual fuel tanks and yesterday I noticed there was fuel coming from the filler cap for the front tank. I unlocked the cap and the tank seemed to be pressurized. Fuel began rushing out of the tank and dumped what seemed like a quart of gas on the ground.
Is there a vent that could be clogged??
If not a vent, what else could it be? Could the warm day have contributed to this effect? As a side note, this truck has a week fuel pump in the front tank but would that be related?
How much of a chore is removing the front tank to get at that fuel pump??
Any help or direction is appreciated!

Thanx, Mike

maybe a gas ferry came over while you were sleeping and over filled your tank for you.

83broncodude,
I guss that's possible but I don't live near water!

Originally Posted by finkster

83broncodude,
I guss that's possible but I don't live near water!

That is pretty funny, he is probably scratching his head over that one...

Your vent tube is probably plugged because it should have leaked from there first. Was the truck running when you took the cap off? I have heard of in tank pumps somehow coming loose or leaking and causing fuel to rush out like that when on. If the truck was running if could be from the heat and being over filled. I don’t know how much of a bear it is to replace.

If you look I think you'll se that the vent tube just goes to the filler neck... and is not vented to the out side (emission stuff)... You may have put to much fuel in the tank and as it heats up during the days sun the fuel well expand and then over fill the tank pushing it out the cap.. with closed systems anymore you need to just not put so much in the tank...
just my .o2
Tim

Thanx GaryWhite7!
I'm glad someone got my funny!!

whoopsie, lol doesn't someone feel like a horses patute.

Okay, here's what I've learned about this phenomenon. Since I have two tanks, fuel can be push from one to another if you have a bad tank selector valve. According to the parts man at the local Ford dealer it is a fairly common issue. There are two types of valves. A 3 port and a 6 port or I guess you could call it the $130.00 valve or the $190.00 valve. Most big blocks, according to the man, take a 3 port ( $130.00 ) valve. Now my question....
Anyone else dealt with this? If that valve is where I think it is ( mounted to the frame rail ), it looks like a bitch to change.
Any good sources for Genuine parts?
Thanx, Mike

I'm not buying it.... How can it build up prusher if the vent is working? I think it was the tank heating up the fuel in the sun and the fuel just expanding in the tank that would make it push out as well. Had you just filled the tanks??
Tim

Bad fuel pump. Check valve is bad and not allowing fuel to return to the correct tank. Common problem on for trucks