Bad gas problem

I just purchased a 1951 Chevy 3100. This my first old truck since they were new. I am having trouble putting gas in the tank. It is the original tank behind the seat. The gas will only go in very slowly or the pump clicks off. Can anyone tell me why and what I can do about it?

 

Just sounds like the issue motorcycles and most old cars have with low-vapor gas nossles. If they don't feel pressure they won't go very fast or keep clicking, gotta press it hard to make a seal or go to a station with less sensitive pumps

 

Maybe the filler neck has an old rag inside. Used as a temp. Gas cap. Maybe the rubber hose connecting the filler to tank has shrunk. Also you. Need to hold the nozzle up a bit so it an get air. My two cents.

 

The filler tube has a vent tube built into it - could be plugged. They are reproduced if you need a replacement.

 

Tums?

 

Or bad gas... yeah, so?

 

I don't know what can be done to correct the problem....My 51 car does the same thing,...If I try to force gas into the tank it will kick off and sometimes gas will spit out of the filler neck onto me etc...I found if I pull back the rubber seal that is attached to the gas filler handle I can get gas into the tank slowly....I think what is happening is the gas going into the tank fast, along with the gas filler handle rubber sealing the tanks filler neck, it does not allow any air to get out of the tank causing a lot of pressure in the tank which causes the pump to kick off,...and in my case spit out gas.Miller

 

That's the way they are.You will have to get used to it. Also don't top off the tank on a hot day. Gas expantion will cause gas to spill out the neck. There are no baffles in the tank,so filling will cause spills also. Welcome to old Chev truck ownership. Lol

 

This is correct. As you put gas in the the tank, the air inside the tank has to escape (vent). The small pipe on the side of the filler neck in this pic allows that air to vent above the gas fill nozzle. The surge of the air coming straight up the fill pipe is what causes the nozzle to shut off contantly. Vent the neck above the nozzle and it will fill like it should.

 

A popular conversion is removing the behind the seat tank and installing one under the bed to get rid of the gas fume smells inside the cab.I'm sure some folks will chime in on how they have done it.

 

Yep - TANKS unit :

 

Thanks, that makes a lot of sense. I will check the vent hose and make sure it is not blocked.