Plugging fuel filler hole

[eric8]

I will be doing an LS swap soon on my 72 C10 so obviously the factory tank is going to be taken out. I'm trying to avoid paint or bodywork to fill in the hole left behind where the filler neck passed through. What I had envisioned is using a rubber type "plug" or blank off that attaches like a firewall grommet. I was curious if anyone knows the diameter of the hole that is left in the cab once one removes the filler neck and factory grommet?

I had also considered welding in a "dummy" filler neck so I could put on the stock gas cap and give the appearance of a stock truck from the outside. Has anyone ever done this? Stupid idea?

[Daddy Brim]

I had also considered welding in a "dummy" filler neck so I could put on the stock gas cap and give the appearance of a stock truck from the outside. Has anyone ever done this? Stupid idea? [/QUOTE]

I like this idea, if you are going to stay with the stock look. If not weld in a plate and try to match the paint.

[eric8]

Originally Posted by Daddy Brim

I had also considered welding in a "dummy" filler neck so I could put on the stock gas cap and give the appearance of a stock truck from the outside. Has anyone ever done this? Stupid idea?

I like this idea, if you are going to stay with the stock look. If not weld in a plate and try to match the paint.[/QUOTE]

Yeah that was my initial concern about the bodywork...not so much the labor of doing the bodywork, but the ability to match the paint and make it look good.

[Eddie H.]

You could slice off the original filler neck from the old tank ( Take it out, fill to the top with water, and very carefully cut it off with a hack saw, so there's no chance of it going boom), then leave it sticking out of the rubber grommet with a cap on it. It would look stock. I would plug it up with something, however, to prevent somebody from accidentally filling the cab up with gas.

[csfields]

Check out the Holley truck. It's a 67 short bed and it's running a LS motor and they left the stock gas cap in place. May have to google it. Nice truck.

[brad_man_72]

You CAN use the stock tank when doing an ls swap...
Or leave the tank in, or cut the front of the tank out so you have the storage.

[eric8]

I probably should have said I'm doing a GM or Aeromotive in tank fuel pump module. And as far as I know, there's no way to make that work in a stock tank. With an inline pump, yes, I agree.

On another note, I recall reading where the rubber filler neck donut grommet specific to the 1972 models was still available new from GM. Anyone know the part number or where to get them?

[Old Glory]

Originally Posted by eric8

I will be doing an LS swap soon on my 72 C10 so obviously the factory tank is going to be taken out. I'm trying to avoid paint or bodywork to fill in the hole left behind where the filler neck passed through. What I had envisioned is using a rubber type "plug" or blank off that attaches like a firewall grommet. I was curious if anyone knows the diameter of the hole that is left in the cab once one removes the filler neck and factory grommet?

I had also considered welding in a "dummy" filler neck so I could put on the stock gas cap and give the appearance of a stock truck from the outside. Has anyone ever done this? Stupid idea?

Just throw away the key and you won't be able to take the cap off.

[tommys72]

Originally Posted by Eddie H.

You could slice off the original filler neck from the old tank ( Take it out, fill to the top with water, and very carefully cut it off with a hack saw, so there's no chance of it going boom), then leave it sticking out of the rubber grommet with a cap on it. It would look stock. I would plug it up with something, however, to prevent somebody from accidentally filling the cab up with gas.

For a stock look this sounds good to me. Cut the neck off and weld a piece to the end so its just the neck sticking out of the cab, put your cap on it and go.

[eric8]

Originally Posted by eric8

I probably should have said I'm doing a GM or Aeromotive in tank fuel pump module. And as far as I know, there's no way to make that work in a stock tank. With an inline pump, yes, I agree.

On another note, I recall reading where the rubber filler neck donut grommet specific to the 1972 models was still available new from GM. Anyone know the part number or where to get them?

Yeah I may go the route of the fake filler neck. Sure I could just leave the old, empty tank in, but I wouldn't want the associated weight penalty. I'm trying to pare down as much weight as possible.

[Andy4639]

Long ago before I welded the hole up in my 71 I left the rubber grommlet in place and bought a cheap plastic gas cap drilled a couple of holes on the inside of the cap and tie wrapped it to the inside of the cab. I pulled it really tight and never had any leaking when washing it.

[cdowns]

you could fill the hole with a rubber chicken head

[72bowtiestepper]

Originally Posted by cdowns

you could fill the hole with a rubber chicken head

Or ...you could just stick a rag in it like the "Farm Truck" (street outlaws) !

[luvbowties]

Originally Posted by eric8

I will be doing an LS swap soon on my 72 C10 so obviously the factory tank is going to be taken out. I'm trying to avoid paint or bodywork to fill in the hole left behind where the filler neck passed through. What I had envisioned is using a rubber type "plug" or blank off that attaches like a firewall grommet. I was curious if anyone knows the diameter of the hole that is left in the cab once one removes the filler neck and factory grommet?

I had also considered welding in a "dummy" filler neck so I could put on the stock gas cap and give the appearance of a stock truck from the outside. Has anyone ever done this? Stupid idea?

I like your simple, highlighted suggestion above: just install a locking cap to avoid someone accidentally pumping gas thru the opening.
Sam