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Topic: full tank? (Read 1665 times) previous topic - next topic

full tank?

any one in here have a problem where they cant get a full fuel tank? whenever i fill up, and set the pump(gun thing) to keep pumping till its full, it'll stop pumping after a while, and the guage will only read 3/4 the way full. i can keep manually pulling the trigger and still fill it up more, but it will still only read 3/4 full. what is it that could be bad? and does this problem happen to anyone else?
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

full tank?

Reply #1
Can you tell by how many gallons you pump in, if it is a gauge problem?
The only thing I can think of that would keep the gas from getting in, is the air can't get out.
The fill pipe goes down into the tank. Once the gas covers the end of the fill pipe, the air has to go out the vent tube. I don't know where the vent is on your tank.

I had this problem on a '71 Torino. On it the vent was a metal tube attached to the outside of the fill pipe. Inside the tank the vent tube curved up to a little dome in the top of the tank. The fill pipe was in the center of the back behind the license plate. The car had been bumped in the rear, tilting the pipe and vent down into the tank.

full tank?

Reply #2
I have a problem with filling my car - it's called $4/gallon gas :D

Like Softtouch said, verify that you're actually filling the tank by how many gallons you can squeeze into it when it's empty. If you're actually filling the tank but the gauge is reading incorrectly it could be a sticking float, a leaking float (if the hollow float fills with gas it won't float as high, giving you an artificially low reading), corrosion and crud in the connector at the tank, or a faulty gauge itself.

If you can't actually get a full tank into it, it could be the above mentioned vent. If the vent is below the fuel level (or plugged) the air has nowhere to go when you hit that level, so you won't get any more gas into it.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

full tank?

Reply #3
this could also be from the parking lot not being level when you are filling your tank, most parking lots are not level to let water run off.  try getting to a pump where the drivers side is facing the road this should allow for more fuel to enter the tank.  when I fill my car the needle goes so way above the full mark and stays there for quite a while, in my 79 cougar the needle leaves the visible part of the guage.

 

full tank?

Reply #4
allright, thanks, ill be sure to let my tank get pretty low before i fill it to see how many gallons i put in there, i guess if its about 22 gallons, its a bad float or gauge. ill try to get back to ya'll after i fill up.
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone