Gas Cap Leak

[guapo2001]

Hello All,

I'm new to the forum so bear with me, I have a 72 C10 with a 307. My problem is I have gas leaking from my gas cap after I fill up the tank.

I assume this is due to my gas cap, does any one have a recommendation on what type is best.

The one I currently use is a locking type.

I have searched the forum for anything on this subject and have not found any.

Thanks for any help, Jon

[AesC10s]

i have this problem also and would like to fix it...

[cdowns]

just go to napa carquest etc and get a nice chrome one it should fix the problem theres really not much of a selection

[AesC10s]

do they have ones that look like the factory chrome twist on one?

[Longhorn Man]

I know they have a stant (plain chrome) for the 70 and older. The locking ones normally leak from my expireance.

[guapo2001]

I was hoping that it was that simple... Just wanted to make sure I wasn't the only one...


Thanks, Jon

[cell]

My original gas cap leaked as well. I picked up a $5 replacement at advance auto. Looks pretty close to the original, but not exact.

[LUV2XCLR8]

From West TN

[Brad]

If you look inside you'll see a rubber or cardboard ring. If that's compressed, it'll allow gas to spill out and not seal effectively. What I did several years ago when I was running the stock tank is make my own gasket out of stiff cardboard gasket material and it worked like a charm!

[WizzKidd!!]

Those locking ones wear out pretty quick. If that rubber seal starts to get old or compressed, it's time for a new one. I've never found a locking one that seals quite like a stock twist on.

[Orange]

The only kind I ever had work with the stock style tank twist on actually was a locking one.

It was ugly as sin, but it worked.

The cap itself was very thick/tall, and had a very thick rubber gasket. I'd say it was about 3" tall overall. It was a different type than all the rest I had tried.

On another note - if you are in the midst of a project, or into bodywork - my CoolCap doesn't leak a bit.

[Robert1970C20rstbukt]

I bought a locking one at carquest for almost 20 bucks, it's about a year old and it's never leaked. This one only fits 67-70, the 71-72 looks different but should have the same gasket.

[Stocker]

Originally Posted by WizzKidd!!

Those locking ones wear out pretty quick. If that rubber seal starts to get old or compressed, it's time for a new one. I've never found a locking one that seals quite like a stock twist on.

I had a locking cap from NAPA that lasted several years before the seal finally expired. Got a new one (2 or 3 years ago) and it's still good.

[jacobs]

Originally Posted by Stocker

I had a locking cap from NAPA that lasted several years before the seal finally expired. Got a new one (2 or 3 years ago) and it's still good.

At one time, NAPA (or was it Stant?) sold replacement seals so you didn't have to purchase a new complete cap.

[farside847]

I definately recommend fixing it though, with the current gas prices you need ever drop!

[deadof_knight]

Buy two and use both seals on one cap, its tighter and I have no problems with that any more . I own three trucks and my boys drive constantly. and 2 of my friends have them as well. This is a Fix.

[Southpa]

I go thru a locking gas cap about every 2 years. Can only find one type, all black. I found that the gaskets dry up and crack. I'm still looking for a vented cap. I can't believe how much pressure can build up on a hot summer day..."WHOOOOSH!" At least I know the seal is good. I might drill a tiny 1/32" hole thru the cap.

[guapo2001]

I found a solution, Go to Lowe's in the plumbing area, they sell this reddish-brown gasket material for a dollar or so. Trace your existing gasket and cut out a new or (in my case) for double thickness and slide it on the cap.

I have had no leaks since, about two weeks...

Very cheap solution...

[see ten]

My cap was leaking as well, I bought a replacement but it just didn't feel as heavy as the original. I ended up taking the gasket off the new cap and installing it on my old cap. It worked like a charm.

[67ChevyRedneck]

What year is your truck? Some years had vented gas caps and some didn't. Something to think about.

[A.P.]

I found a solution, Go to Lowe's in the plumbing area, they sell this reddish-brown gasket material for a dollar or so. Trace your existing gasket and cut out a new or (in my case) for double thickness and slide it on the cap.

I have had no leaks since, about two weeks...

Very cheap solution...

guapo2001, do you happen to know the name of the material you use? I went to Lowe's and could not find it.
A.P.

[c10crazy]

Make sure the Lowe's stuff holds up to petroleum products!. If not, it could deteriorate from the backside and before you know it, little pieces of it could fall in the tank and clog the fuel line.

[Green Machine]

Also take a close look at the tangs inside if the tank neck. They can get bent from the gas nozzle or whatever. Sometimes they need to be tapped back down or straightened, also make sure the top surface of the tank neck is nice and flat and even height all around, that will make the cap sit tighter, just try not to make too many sparks if it needs some adjustment !!!

[70c10]

Originally Posted by Green Machine

Also take a close look at the tangs inside if the tank neck. They can get bent from the gas nozzle or whatever. Sometimes they need to be tapped back down or straightened, also make sure the top surface of the tank neck is nice and flat and even height all around, that will make the cap sit tighter, just try not to make too many sparks if it needs some adjustment !!!

Good point about the tangs being bent. Mine were!. Use a block of wood to tap on to eliminate the chance for sparks