Could have blown up both the car and the house.

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Bills65Dart

Bills65Dart

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Hello everybody.

We had some really hot days here like a week ago or whatever, 110, and the Dart that was sitting outside the house started to smell gas.

Started the car, drove out of the driveway to place it out in the street, and suddenly I see a wet and shiny spot that would have been under the tank when the car was parked. Drove it up again, and opened the gas cap, and it was a lot of pressure in the tank. After letting that out, the dripping of the gas stopped, and have not happened again.

So, I can not live with it like this. The cap is not vented. And from the service manual it is not supposed to be either. There is a little tube from the top of the tank and up to the neck just inside the cap, but I assume that is for letting air out of the tank itself while filling at the gas station. It does not look to me as a tube that is supposed to let gas fumes out, because then it will pretty soon be unbarable back in the trunk, and inside the car too at some point.

So, what is missing here ? I have been thinking if I remove the rubber gasket, it will not keep the pressure in the tank, but then the cap will actually be vented, and it is not supposed to be that.

I put a new rubber gasket / seal on the cap last year, the old one was in pieces. I used 1/16 nitrile rubber sheet for that job.

Bill
 
I believe 65 has a tank vent.. It is a small tube up by the fill tube in the trunk. Take some compressed air and blow it out From the tank outward. It is probably plugged.
 
toolmanmike said:
I believe 65 has a tank vent.. It is a small tube up by the fill tube in the trunk. Take some compressed air and blow it out From the tank outward. It is probably plugged.
Click to expand...
With gas cap off, and low pressure.
 
Yes, there is a tube, it comes out on top of the filler tube, 1/4" or so, then a little rubber hose, and a new tube that goes up around where the left trunk lid hinge is, and then finds it's way down and into the gas tank where the filler tube goes in. So, I assume that is connected to the tank too, to let air out of the tank when fillling. Or is it something I am missing here ?

Bill
 
Bills65Dart said:
Yes, there is a tube, it comes out on top of the filler tube, 1/4" or so, then a little rubber hose, and a new tube that goes up around where the left trunk lid hinge is, and then finds it's way down and into the gas tank where the filler tube goes in. So, I assume that is connected to the tank too, to let air out of the tank when fillling. Or is it something I am missing here ?

Bill
Click to expand...

What does your cap look like?
 
Believe it or not the caps are supposed to be non-vented. Today's gas get's close to vapor at a pretty low temp. That can build up pressure.
 
Problem solved. I took off the little hose in the trunk, where the tube is connected to the filler neck. and connected my blow gun t the tube, and thought to myself that if it is plugged, it will shoot whatever is plugging it inside the tank, and having the cap off as suggested, it will not blow up the tank. I gave it full air pressure, and the gun shot came, at least like a caliber .22. Now, I tried t continue to blow, but it sounded like the air came from under the car. And now I had someone else holding the airgun, and I found the end of the tube under the car. And not inside the tank as I assumed it was. Thank you for your help


Bill
 
Ok, now go jump the barn...

holdmybeer.jpg
 
Bills65Dart said:
Problem solved. I took off the little hose in the trunk, where the tube is connected to the filler neck. and connected my blow gun t the tube, and thought to myself that if it is plugged, it will shoot whatever is plugging it inside the tank, and having the cap off as suggested, it will not blow up the tank. I gave it full air pressure, and the gun shot came, at least like a caliber .22. Now, I tried t continue to blow, but it sounded like the air came from under the car. And now I had someone else holding the airgun, and I found the end of the tube under the car. And not inside the tank as I assumed it was. Thank you for your help


Bill
Click to expand...

Yes my '67 was set up the same way with a vent tube looping up the filler neck by the gas cap, back down again through the trunk floor, and venting out next to the sub frame rail.

Glad you got it . . .
 
That's the ticket!

Something that can happen if you top off the tank... the cool fuel from the tank in the ground will heat up and expand. If it is full enough it will flow out the vent or a leaky filer cap.

Had a 56 ford PU do it often. Always an adventure to get into the cab that reeks of fuel and turn the key.

Click click booooom
 
Those vents work well when they are working. AND NOW an annoying story from the old days

Many of you may be aware (codes may have changed) that any electrical/ combustion/ ignition sources in a garage must be 18" above floor level

Back in the day when I worked for a large industrial/ parts store here, "everybody" was hanging saddle tanks on pickups. Guy came in, wanted to know what he needed, I showed him electric and manual valves, explained he must check for a return system, totaled up an estimate of filters, clamps, hose, etc. and he thanked me and left

Some time, weeks? later he came in and waited for me, told me "what" and "did I remember him? "Yep" So he bought some fuel system parts and a changeover valve and then "confessed"

Says he "saved all this money" cuz he teed the two tanks together went down filled it up and parked it in th garage. He said he went out there later and THERE WAS FUEL ALL OVER THE FLOOR. The thing is, he said, there was a gas water heater in a corner closet and NEITHER of us could believe that thing didn't go sky high!!!

(One tank was slightly lower, he had filled up both, and one siphoned into the other and ran out the vent)
 
Bills65Dart said:
Problem solved. I took off the little hose in the trunk, where the tube is connected to the filler neck. and connected my blow gun t the tube, and thought to myself that if it is plugged, it will shoot whatever is plugging it inside the tank, and having the cap off as suggested, it will not blow up the tank. I gave it full air pressure, and the gun shot came, at least like a caliber .22. Now, I tried t continue to blow, but it sounded like the air came from under the car. And now I had someone else holding the airgun, and I found the end of the tube under the car. And not inside the tank as I assumed it was. Thank you for your help


Bill
Click to expand...

That's right. It just vents right through the trunk floor to the outside of the car. Sounds like you fixed it!
 
As you found out that little tube vents through the filler to trunk pan gasket and either into the the frame rail pocket or just to atmosphere.
 
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