HELP- 1984 GMC 3500- fuel leak from tank

[2badgn]

I had a new fuel sending unit installed months ago by my local Chevy delaer. When I noticed after the unit was installed that the gauge was better but not 100% accurate, I brought the truck back to my dealer. Dont know what they did but now I have fuel leaking from the tank. THe truck was at the dealer for 2 weeks and the tank was full when I brought it there. It was near empty when I picked it up today. They fixed my horn by replacing the turn signal switch but now I have a fuel leak-- ARRRRRRR!!!!

I tried tightening the bolt on the side - but it kinda made it leak worse. By loosening the bolt a little, I got the leak down to a drop- Have a bucket under my truck now.

Didnt try tightening the other bolt bc I didnt know that it was also leaking but much less than the bolt on the side. Going to bring it back to the dealer. But in the meantime, do u think that its a washer or do I need a new fuel tank? Help please- Want to fix this ASAP.

Thanks
Frank

[str8axle55]

I would say tank, unless the new sending unit is leaking and running down the tank. Can you see the sender between the cab and bed, does it look wet? The nuts/bolts an washers don`t go into the tank.

[dman1982]

it could be the tank or the sending unit...i did this about same job on my truck when i got back from iraq, the tank started leaking so i pulled the tank and patched all the holes....if the dealership didnt replace the rubbing lines going into the sending unit it might just be the lines...they are kinda a pain in the a$$ to change out...at least for me anyhow.

[codydubb]

Looks about like one of my tanks did dripping from that same area. bad place for dirt and crap to get stuck between the tank and that plastic cover, rusted right through my tank.

[GmtGmt]

rusted out tank...

[Gregs71]

Not sure if you are aware, but that plastic is just a shield to protect from debris. Unbolt those bolts (they only hold the plastic cover on) and take a look at your gas tank (which is secured by large steel straps-which are kinda difficult to remove).
If the fuel is leaking from the bottom of the metal tank you have a hole, if its leaking from somewhere on top of the tank it could be a fuel line, or gasket.

When I removed my plastic shield I could see a small pinhole where the fuel was leaking from-in fact the whole corner of my tank was swiss cheese...

[texastruckjunky]

I had the same problem, but mine had a little pebble wedged between the plastic shield and the tank that rubbed a small hole in the tank. So i replaced the tank and left the plastic off. Problem solved.