can't afford to loose anymore brain cells - fuel tank issue

[jerry]

holy crap...

drove my malaga car to brisbane on saturday with no apparent issues other than a pesky electrical leak which hopefully has been identified.

....but, apparently, my new issue only made its presence known with a full tank of gas. after treating my car to the 'highest-priced' gas it wasn't long before i was wiffing petrol fumes in the cabin. big time.

down came the door window, but to little effect. it was a 30+ mile commute to work this morning (its first ever, btw) and i'm still a little spacey... good thing i had a fire extinguisher in the cabin, just in case.

apparently, the vent on the plastic filler tube is not sufficient to relieve gas pressure and the other hard tube near the gas line was plugged (by me, i suppose). the impact was not noticeable on a 1/2 tank of gas, but after a fill-up, wow!!!!

i'm gonna really miss those brain cells....

where do i connect that plugged line to? does it go to the vapor box dangling from the trunk top? the car's a late-71 model. there's more than just vapors escaping it seems.

[Guest Anonymous]

Let me re-inforce what appears to be very similar symptoms in my car (2002, non tii, built on 7/6/71). No gas fumes/smell as long as I keep the tank at 3/4ths or lower. But fill the tank to full... and literally get "gassed out". Obviously has to do with the top of tank having gas in it. I have tolerated this because I hope to replace/refurbish the tank and trunk floor pan next winter, but since Jerry posted his problem, and it sounds so much like mine, I thought I'd jump in too. TIA.

Roger

'72 Malaga

[Arizona02]

What year is your car.

Did you pop open the rear windows, it should help the air exit the cabin.

[BillyTheKid]

Replace the fuel sending unit seal.

cheers,

bill

[BillyTheKid]

Replace the fuel sending unit seal.

cheers,

bill

[ClayW]

After replacing the fuel lines back there, I noticed the problem. Look on the right side of your tank at its seam, just below the filler tube. This common rust spot on 02's creates a small gas tank leak. I replaced the tank with a non-rusty unit and the problem was solved.

Again, I had exactly the same symptoms on my `70: Only smelled when the tank was over 3/4 full....and it sucked. I bet you'll find that your tank's seam is rusted.

[DanOKC]

If none of the other suggestions pan out, I had to replace the rubber coupling part from the tank to the cap, I had tried cleaning the area where it sealed & didn't help, but replacing the rubber part with another good used one fixed my gas smell problem, and if you go to get one, some are different from different years, just like the tanks.

[Guest Anonymous]

It's been a while since I've posted on any '02 message board. I used a combustible gas detector to track down the source of gas fumes inside of my '02 and the trunk. Here's where I found gas leaks in my '02.

1. In the trunk, there is a little plastic tube spacer that's around the metal tube of the tank filler. Mine was cracked and everytime, the pump would draw gas, it leaked a tiny drop or two on top of the tank.

2. The unused return hose on the tank was cracked in several locations. Probably has never been used since the '02 was converted over to the Weber downdraft carb. The fabric outer coat looked pristine, but the rubber hose underneath it was toast.

3. On the side of the car underneat the dashboard where the fuel line exits the internal of the car and goes through the firewall, the fuel line has a 90 degree bend in it. Mine had hairline cracks at the bend of the fuel line. That was probably the major source of the gas smell. What can you expect from 30+ old plastic.

What am I planning to do about this? 1. Run a new gas line on the exterior of the car underneath it. Summit Racing sells 1/4" and 5/16" OD soft stainless tubing for a reasonable price. You could also go with rubber hoses w/ a stainless steel braid too.

2. Get rid of the 30 year old charcoal cannister and vent the tank underneath the car somewhere like the Euro '02 did. The motorcycle motocross parts houses sell a tiny combo check valve and vent cap that does the job and keeps crap out of the line. The cheapest I found was $7 at www.motosport.com. It's called a Turner Vent Cap.

[jgerock]

My 73tii also leaks when I fill it all the way up - but my leak is from the pickup plate. I've tried to bend the tabs on the plate to make a tighter fit using the original o-ring, but it still leaks (even after using sealant). Is the plate supposed to tighten to the tank opening like a threaded bolt, or is it a fraction of a turn? A new O-ring is on order now.

[jgerock]

Just received the new plate gasket -- but I received a flat one with (8) holes for use with a bolt-on plate. My tank uses the o-ring for the serrated plate. Previous owner must have installed an earlier tii tank.

[vintage_car]

mine is having similar issues...maybe I can chime in and see what others think about this. I have resealed my tank, new o ring, new fuel hoses. I rerouted the vapor hose to under the car. I filled the tank up, drove around a bit, and was pleased! Then after the car was stopped for about 10 minutes after about a 15 minute jaunt I heard fluid leaking...it was fuel being pushed out of the vaopr tube. I put the vapor tube back to the original location which was in the filler neck and then the tank started pushing fuel out around the new o-ring and even appeared to push it out around the sending unit electrodes...very odd. When I tried to remove the gas cap iafter all this was happening it was very difficult and made an air lock release sound when I finally twisted the cap off. I have a carter fuel pump, and I'm wondering if it has somehow went bad and started to pressurize the gas tank? Would the gas tank get that much pressure in it to actually push fuel out? Please help been fighting with the smell to long!