Gas Filling Problem (California)

[pwjimmy]

I have a 1974 Jimmy and every time I fill it up, I have to pump the gas very slowly and even then it often overfills and runs down the side of the truck. This weekend, I will check the vent pipe for obstruction, but based on the threads I have seen, it seems that this is a common issue with the California gas pumps and trucks of my vintage. But just looking at the aftermarket fuel filler necks, it seems that the design of the 1979-1991 trucks is much better (the neck angle makes more sense).

I was thinking of simply changing out my filler neck (and maybe the tank if necessary) and putting in a 1982-1991 system. The 1982-1991 has a wider neck so should handle higher gas flow. Has anyone ever done this? What I don't know is what the area around the gas cap opening (behind the filler door) looks like. I would appreciate it if someone could take a picture and share it. Obviously in my year, there was no filler door and the gas cap is flush with the body. I am assuming the later years the gas is angled like you see in modern cars.

I am just sick and tired of the hassles getting gas into my truck (not to mention what spilled gas does to the paint job!)

Thanks in advance for any help you can provide.

 

[Babaganoosh]

I have had this happen on my 82 and 85 I had with new pumps and no restrictions it popped the gas pump to stop. I have to turn it sideways or flip it upside down for it to auto pump.

Not a fix by any means but it works...

 

[Polymath]

I don't think that's just a california problem. A lot of gas pumps have those new seals that are supposed to keep fumes from traveling upward because new-ish cars all have vent/vapor systems that are supposed to push fumes through charcoal filters before going up into the intake.

I haven't researched it much but I think the problem is that old cars (and cars with clogged charcoal cans) are unable to vent when that stupid seal does its job. So the fumes build up and the pump handle trips. I have an '02 suburban that does this and the charcoal can was discontinued long ago. Kind stuck filling it up sloooooowly for the time being.

 

[centexk5]

Costco and my rzr don’t mix. I can’t get the nozzle sealed well enough against the pump and it just trips it constantly.

 

[Blue85]

I have an '02 suburban that does this and the charcoal can was discontinued long ago. Kind stuck filling it up sloooooowly for the time being.

I don't know when it started, but my '05 has a vent solenoid, which fails every so many years. You know when it's stuck because you can't get gas in the thing. I'm pretty sure that valve could be modified to be always open - you know, as a "temporary" fix.

As for the super-ninja-shut-off-happy pumps, it can be faster to fill a gas can and pour that in the tank, especially if you have 2 people to alternate. Although with EPA-approved gas cans, maybe not.

 

[Blue85]

Is the problem with the size of the vent or that the fuel nozzle is dumping fuel above it?

My only relevant experience was with an RV fresh water tank. When filling, the vent was initially silent, then hissed, then gurgled and eventually about a quart of water would shoot out like a geyser. I took the vent line all apart and cleaned some crud out that was almost blocking it. After that, the vent was hissing immediately and no more problems.

 

[Cucv_M1008]

I have had this happen on my 82 and 85 I had with new pumps and no restrictions it popped the gas pump to stop. I have to turn it sideways or flip it upside down for it to auto pump.

Not a fix by any means but it works...

I have to do the same.

 

[Wes Harden]

The 74 will have a 1/2" tube venting to the fill neck just under the cap. Is possible it is plugged ? Maybe, I always have to hold the nozzle, close the switch in the recovery boot, and meter the flow by hand in CA. 40gl fill it sucks. I do love AZ no boot per say, still have to use the slowest setting on nozzle