Ford 3000 gas cap won't tighten

[banc123]

I've replaced the gas cap a few times over the years because they eventually won't stay tight, begin to jiggle allowing fuel to splash out on bumps etc... The only replacement ones I've found are round Crome ones on eBay/Amazon and when put on tighten, but EASILY jar loose or continue to turn with some friction but will come loose soon after using. The tank fill neck has a pin hole in it, so seems the cap would be ventless, but they look like they have a piece on the underside of the cap vs solid cap.

I've ended up only being able to fill the tank 1/2 , gently tighten the cap and duck tape the dang thing so it won't jiggle loose. Even then it eventually jiggles around but at least doesn't come off.

Was wondering if there was some kind of adjustment that could done to the cap or lip on the tank etc...

Thanks.....

 

[treefarmerguy]

If I remember correctly, the cap on my 4000 had two ears on it that engaged two slots on the tractor tank fill opening. I think the ears on the cap can be bent to make it fit more tightly.

 

[3Lfarms]

Ive had good luck using a large O-ring in place of the factory flat rubber gasket in applications like that. The o-ring will provide a good seal and deform enough to keep the cap tight. You just have to find one the correct size so that it stays put in the cap when you remove the cap to fuel up.