Gas Tank Woes...Still

[daniel3507]

Ive had problems with my gas tank leaking when i fill it more than half full. Spent the money and had the filler neck replaced and it still leaks. So i just wasted all that money for nothing. At least I narrowed it down i guess. What else could it be? Fuel pump seal? There cant be that many things that could cause a leak.

 

[BRUTUS_T_HOG]

where does it leak? off the lines as if it is siphoning? or out the top of the tank?

 

[daniel3507]

I cant see exactly where it comes from. It runs down the sides from the top it looks like

 

[BRUTUS_T_HOG]

you'll have to remove the truck bed or pull the tank from below and replace the fuel pump module seal. you can also check for a leaking vent on the top of the tank

 

[daniel3507]

How many other things are coming out of the tank? I would think the fuel pump would be the only thing left. Im just trying to avoid buying another part i dont need.

 

[BRUTUS_T_HOG]

there is the fuel pump module (plastic thing that the fuel pump is mounted in, also includes the fuel level sender) and then there is sometimes another vent hose on top(not the one for the fill tube)

the fuel pump module just has a big round O-ring to seal it, if its old it might be oxidized and cracked.. or if somebody removed it before they might not have gotten in on right..

 

[daniel3507]

Is that on the very top of the tank? Im thinking i may have a crack in the side of the tank since i cant fill it up more than half

 

[mp3deviant721]

Yeah. It could be your tank cracking in the middle. That really makes sense if you say that you can't fill it more than half full.

 

[legoms013]

Might be the fuel pump gasket on the tank, but if its leaking at half full then its more than likely its a crack or something on the tank.

 

[raymondvillain]

I had to replace the fuel tank on my '86 due to the same problem. It turned out that somehow, mud and wet concrete had been deposited on the top of the tank. That trapped moisture between the goo and the metal. Consequently the metal rusted and eventually the pits formed by the corrosion went clear through. Everytime I filled up the tank, gasoline would ooze out of the holes and trickle down the sides of the tank.

 

[daniel3507]

I have heard of metal tanks rusting out but mine is plastic. I have no idea how it cracked but oh well. Just gotta get it replaced now.

 

[Loud Ranger]

I have heard of metal tanks rusting out but mine is plastic. I have no idea how it cracked but oh well. Just gotta get it replaced now.

I feel your pain, my tank leaks if i fill up too fast but if i go half speed on the pump handle it wont leak at all. It takes forever to put gas in it.

 

[hoosier1104]

I had a similar issue on a BMW, I know I know, I owned while stationed in the UK. They had a petrol sealer clay you put on the outside of the tank which stopped the leaking. I do not recommend this but for a last ditch effort I would give it a try.

 

[feellnfroggy]

I had the fuel pump replaced on my mustang, actually the tank was replaced, swapped the pump. And because the bottom of my tank was dented from the accident the pump was tilted and wedged. He had to knock out the dent, well when he did that he bent the opening where the fuel pump sits just a little. And the lack of seal allowed fuel to spew all over the place.


Me personally I would buy alot of 1/4 inch sheet metal (maybe 1/8 inch 1/4 is pretty think) and custom design my own fuel tank without all the curved corners and such. You can buy them but they are expensive, but youll get about 5 gallons more capacity this way, and sheet metal can be emptied dried and welded when you have problems like this.

 

[kossdust]

why not just pull the truck bed and inspect the tank before you purchase new one? I would think a crack would be easy to spot. If not fill it up and see where it starts coming from. That way you will know for sure if it the seal or if it is the tank.