Is There a Gas Cap that Doesn't Rot-out Quick?

[DJ_Baar]

Anyone have any luck finding a replacement gas cap that the rubber will last at least a little while? This one is about a year old and already cracking.

[special-K]

It's your fault for exposing it to gas fumes. No, and sorry, just kidding. That is ridiculous. I haven't had to buy a gas cap in so long I have no idea what it good today. Does Stant still offer them? I'd buy from a company like that, it's what they do and have been doing forever, sooner than one offered by a 67-72 GM Truck parts supplier. Those might be Stant as well, but when you buy Stant you know you are getting Stant… if they are still any good.

[DennisP]

I feel your pain. I've gone through 3 gas caps in the last 5 or so years. Buying the Counterpart locking ones. They seem to leak after a year or so. It gets so I don't fill the tank all the way because of this. Next time around I am going to try a different brand.

[Steeveedee]

I had terrible luck with locking caps, even from Stant. Maybe a couple of years, and the gasket is gone. I just have a chrome Stant non-locking cap. It must be on there about three years, now.

[Fbks_Cruiser]

I have had the same problem. Instead of buying a new cap, I cut a new rubber gasket. I used some stuff made for flat roofs. It seems to be holding up well. ( At least longer than the original one did.)

[DJ_Baar]

Thank you all for the replies.

I heard I need to find a good rubber supplier and simply replace the gasket. Not so sure about that - finding good Supplier that is.

I have this ol'67 C20 about 95% complete - its the replacement parts that I am still having to get working right. Go figure?!

[special-K]

Is yours locking or regular. I hate locking caps. I'd rather let someone steal my gas . Actually, I am fortunate to not have to worry about such things. I wonder how wiping gas resistant RTV or similar on the cranked gasket would work. Do it a few times to build it up. Who cars? You are the only one who sees the backside and only when you get gas. And I never look then either. It's a cryin; shame when you are better off with a 20 year old cap than a new one.

[bowtie72]

If you use epdm rubber it is suppose to be chemical resistant. I am going to try it on both of my trucks. It’s frustrating turning corners and puking gas out.

[Astro-Balls]

Make your own Gasket..
https://www.grainger.com/category/ra...&filters=attrs

[burb71]

I only fill up with Ethanol-free gas in my old trucks, haven't had to change rubber fuel lines since.
Maybe its also easier on my gas cap.

[dmjlambert]

I'm sure non-ethanol is easier on your rubber, depending on what you have. I can't get ethanol-free for daily driving, it is too far away and too expensive. I had trouble with Stant cap rubber deteriorating and wrote to Stant to specifically ask them about the rubber and to complain about how it starts cracking and breaking up immediately. They wrote back to say they had no plans to change, they are happy with things the way they are, and denied the cap is made out of inappropriate type of rubber. So, I've bought the last Stant cap I ever will, I threw it in the trash, and even if they do come to their senses I won't be changing my mind. Stant is burned into my brain permanently as the wrong brand to buy. I bought a United Pacific Locking Gas Cap S1301 from Summit in Jan of 2017, and it has shown no deterioration at all since then, I just went out to the truck now and examined it. Ethanol does not deteriorate rubber that is formulated properly.

[burb71]

Originally Posted by dmjlambert

I'm sure non-ethanol is easier on your rubber, depending on what you have. I can't get ethanol-free for daily driving, it is too far away and too expensive. I had trouble with Stant cap rubber deteriorating and wrote to Stant to specifically ask them about the rubber and to complain about how it starts cracking and breaking up immediately. They wrote back to say they had no plans to change, they are happy with things the way they are, and denied the cap is made out of inappropriate type of rubber. So, I've bought the last Stant cap I ever will, I threw it in the trash, and even if they do come to their senses I won't be changing my mind. Stant is burned into my brain permanently as the wrong brand to buy. I bought a United Pacific Locking Gas Cap S1301 from Summit in Jan of 2017, and it has shown no deterioration at all since then, I just went out to the truck now and examined it. Ethanol does not deteriorate rubber that is formulated properly.

I had to change out my rubber fuel lines on the same truck a 3 times in a years time, I bought gates it rotted, cracked & leaked then I got one rated for fuel Injection, it rotted, then someone told me it was the ethanol in the gas, so I switched to eth-free and all has been good

[toolboxchev]

Originally Posted by DJ_Baar

Anyone have any luck finding a replacement gas cap that the rubber will last at least a little while? This one is about a year old and already cracking.

Don't worry about the cap, rip that rubber crap thing off there and head down to your Local ACE. In the nut, bolt, specialty fastener section I would bet they have a thicker rubber type product that works fantastic.

I got one for my Napa cap, and not looked back. How's that for the Mother of Invention?

[67C10Step]

I keep a sheet of viton around to cut my own gaskets when needed. Noticed my five month old gas cap gasket was already curling. Nothing but non ethanol fuel in the tank.

[jgrote]

I bought a replacement rubber seal for my gas cap on my 66 Mustang, and after 2 years it still looks brand new. It looks to be about the same size. I got it from NPD, and it was ridiculously cheap. If you can give me ID and OD measurements, I'll be happy to compare.

[Astro-Balls]

https://www.npdlink.com/product/gask...%3D0%26year%3D

[DJ_Baar]

More great feedback, thank you.

I use a non-locking gas cap and have used only non ethanol premium gas.

[71gmcC15]

I bought one frome running. I can't remember what the brand was. It was for a tractor. Fit my pickup just fine. Still holding up good.