1973 Gas Cap

[Number21]

Some jackass stole my gas cap. I have bought two caps now from two different places for a 1973 fleetside "without evaporative emissions" and neither fits, the opening is too big.

Can somebody tell me how I know if my truck has the "evaporative emissions" system? I didn't think it did, but it must if neither of the gas caps fit. Can anyone do me a favor and measure the diameter of their '73 gas filler neck?

Does the "evaporative emissions system" have a larger filler opening?

[463]

here is some caps http://www.rockauto.com/catalog/x,ca...,parttype,5900
evaporative emissions lable may still be under the hood on the rad suport will tell you for sure.

[76stepsidechevy]

That sounds like you have the bigger non emmisions filler neck. maybe its the parts guy just grabbing the first one they see off the rack. I know theres a small rack of them at the local parts store here, I was able to find one there for my 76 stepside with the large filler neck.

[Number21]

Ok, I took the cap back and got one for the truck with "evaporative emissions" and that doesn't fit either! WTF?!

Did 73-78 with the cap on the bedside use the same cap?

[Number21]

Originally Posted by 76stepsidechevy

I was able to find one there for my 76 stepside with the large filler neck.

I believe the step sides and the fleet sides have different caps, am I correct?

[Number21]

While we're talking about it, does anybody have any idea what I can plug the hole with temporarily? I can't drive without my gas cap! I tried a 2" plumbing test plug but it's just a hair too big.

[Phillip Pennartz]

for something thats just temporary might try duct tape

[Zane M]

Originally Posted by Phillip Pennartz

for something thats just temporary might try duct tape

I've duct taped many a filler hole as a short term solution.

[Axle]

If your original cap a 1/4 turn cap? If so, try to find a cap for a leaded fuel truck. Might have to go back a few model years though to get to the correct style.
Take a photo of your filler neck if you still have no luck, then we can see what style it is.

Alex.

[Number21]

Here's a pic of my filler neck. I took the truck down to Napa and they couldn't find anything to fit, the guy thought maybe the neck was bent possibly from somebody trying to steal gas. I think I'm going to have to replace the filler.

[Breadman]

I got one at Advance Auto Parts

[88Jimmy4x4]

The difference is in the TANGS, 76-up used 2 long tangs and 2 short, 73-75 had shorter TANGS.

Here is a NOS 73-75 Fleetside cap I bought by mistake (on left) and the 76-up (on right).

I found this out the hard way and now have the 73-75 cap I cannot use.

[88Jimmy4x4]

Mesurements of the short tang cap I think you need is 3-1/8" dia overall, tang edge to edge is 1-5/8" and center round is 1-5/16" dia.

[Number21]

Originally Posted by 88Jimmy4x4

The difference is in the TANGS, 76-up used 2 long tangs and 2 short, 73-75 had shorter TANGS.

Here is a NOS 73-75 Fleetside cap I bought by mistake (on left) and the 76-up (on right).

I found this out the hard way and now have the 73-75 cap I cannot use.

Yeah, those are the caps I've tried. Neither fits....

[88Jimmy4x4]

You sure you tried both style tangs?.....thats the only 2 styles GM ever made for the exposed caps aside from the stepside style which I have too.

You can get a new filler neck from LMC for fleetsides, might be your best option at this point.