Ok, So my fuel gauge does not work so when I take the car out i tend to put in gas not knowing how much is in there. today as i am putting gas in I notice a big leak from the front area of the tank as I am filling so I take it home as the station is close. it has not leaked before. When I get home there is no fuel leaking. I turn around outside of the house and do slow doughnuts and it leaks a little then stops. When the car is still no fuel leaks.

Could the tank be over full and splashing fuel out of the vent lines? Any way to check and see? I did not want to drop the tank to do the sending unit until I am ready to do all the lines and a new tank and pads as well. It appears he fuel is leaking from the passenger side of the tank.

thoughts and ideas?

 

It could be that the rubber vent hoses have deteriorated and cracked if they are original...you do not need to drop the tank to change the hoses...but it could be the circular rubber seal on the sender that is top mounted on your tank...that needs a tank drop

 

My suspect is this also.
The old hoses on mine were the originals and very cracked.
Replacing them all caused my garage NOT to smell of fuel anymore!

 

So I have been thinking about this, when I was pumping gas and it started to leak it was gushing and not just dripping, The car was not on an incline and when I got it home in the drive way it did not leak when it was parked flat.

If the tank was overfilled would the tanks fiill tube have fuel spilling out before a vent tube? Could the fuel that is still leaking just be the excess that had leaked and puddled somewhere and the motion is allowing it to run if it did overfill and come out of a vent tube? This sounds like a dumb question, but since the gauge does not work how can I find out if the tank is just to full and overflowing somehow?

 

I have filled my tank until the auto pump shutoff activates, with no (known) leaks.

A gusher is a big problem. Time to get it up on ramps and look for possible leak areas. There should be evidence where it leaked. Replace the hoses, if they look deteriorated. This needs to be done anyway. Make sure all the hoses are there, too!

 

Dropping the tank is not a hard job, just drain it first, a leak at the seam is the most common, but as others have stated, check the rubber lines, and replace.

 

It's supposed to work this way or evey time anyone filled their gas tank, the fuel would start leaking out of the vent tubes before the level reached high enough to shut off the filler nozzle.

The vent tubes don't just come out of the gas tank any which way. They are angled upward and attached high up under the car so that their outlet level is well above the top of the tank. Otherwise I think what you suspect is happening actually would happen, and fuel would leak out of the vents before the nozzle shut off.

I think you have leaking or missing vent tubes, or the vent tubes are there and in ok condition, but they've come loose and are not in the proper position. You'll have to jack up the car and get under there in front of the tank and take a look. Replacing them is easy once you have that access. When I dropped the tank on my '67 Delta to replace the fuel gauge sending unit, I used the occasion to replace the vent tubes as well. I took the old ones with me to the store to get replacements of the same diameter and length. There are two vent tubes on my tank, each a different diameter. I'm not sure why. But they're replaced!

What's been said is correct in that you do not have to remove the tank to get at and replace the tubes. Just jack the car up securely and crawl under there.

 

Thanks for the response guys.

I will get it up in the air this eve and see what i find.

I guess where I want to believe the tank was just overfilled is because I have put gas in it numorous times and just a couple days prior. it did not leak on the way to put gas but did during putting in gas.

 

I had this happen a few months ago. Replaced the hose and no more problems. My money is on a bad hose.

 

Well guys what do you know, a rubber hose that was so ripped it was like not even of having one one. Must have been that way for some time and never noticed.

The car actually accelerates better and does not seem to bog down on full throttle...or maybe I am imagining it

Thanks for the ideas as always, it is just easier to get ideas from others who have had similiar problems to help isolate the problems...

 

You probably are, but maybe not. I always think my cars ride better after I wash and wax them. In your case, the bad hose might have interfered with proper venting of the tank, which would interfere with fuel flow out of the tank. I have no idea if this is the case. Just a guess.

But I'm glad to hear you found the problem.

 

If you replaced the suction hose from the tank to the pump, and it was cracked enough to allow the pump to suck air, then performance would be improved.
I think there were about 7 hose pieces under there, some 5/16" and some 3/8".
Half of mine had GM stamped on 'em...

Glad it was an easy fix.