Ladies and Gentlemen,

When I fill my tank up completely up I have noticed that gas will leak out of the filler tube when the car is sitting still (meaning for hours while I am at work). It seems to be especially bad on hot days, however, it will also leak when the weather is cool. I am assuming that pressure is building up and causing the gas to run up and out of the filler tube. It leaves a very large puddle, or stain, because of the endless dripping. This is only a problem after I fill the tank up completely and is getting to be really annoying/embarassing/costly/stinky (you can really smell it inside the car too!), and probably not too good for the paint.

I have replaced the gas cap a few times but it does not stop the leaking. I have a locking gas cap on it and am wondering if that just does not work. Has anyone else had this problem and if so, how have you solved it? Thank you for your time.

I think that '68-72 are the same. I too have a locking cap, too easy to siphon compared to newer cars. Mine does not leak when full and hot out. If it did it would not hit the paint though, it would drip onto the inside of the fender. I'd guess that your vent tube is either clogged or kinked.

It doesn't sound like your using a vented gas cap. IF so make the ball is loose. If not then some caps can be taken apart where the screws are.

I have the same problem. It is really bad when i make a right turn and the gas is sloshed towards the cap. tried the original cap & new replacement. Same result both times. Man does it smell! It is a repro tank. Could the tank be the culprit? There is no vent tube on a 68 El camino.

I have had the same problem and it turned out to be a cracked solder joint where the filler tube meets the tank. Get your torch out.

Get your torch out.
But first evacuate the subdivision :eek:

My 67 El Camino does the same thing. I have to always be aware of it or I end up with a puddle of gas under the left rear tire. :sad:

Is the problem with stock parts or replacement parts, or both? Those with the problem, what do you have? I don't remember having this problem with my original parts. Scott

My 69 has done this a couple times as well. It only happened when it was completly full on a hot day just after filling up. My tank is origional. I think my
cap is not vented but should be.

Let's see.....I know that the 69 elkys are opposite of the Chevelles as far as vented caps vrs. non-vented. I just can't remember which it is. :clonk:



****EDIT.....69 elkys use a VENTED cap....../EDIT****

My elky had the exact problems,turns out the leak was where the neck meets the actual gas tank.I cleaned out the crevice around the area and resoldered. that seemed to have fixed it.

My elky had the exact problems,turns out the leak was where the neck meets the actual gas tank.I cleaned out the crevice around the area and resoldered. that seemed to have fixed it.

Did you do this or take it somewhere? I would be very hesitant to try this myself because of BOOM!

Mine leaks too but I wonder about the guys you say the leak is at poor solder joint...my tank/neck are original as have my last 10 Elkys, they all had a rubber grommet with a slip fit fill neck.

I intend to solve it for good...Fuel Safe fuel cell. :)

Let's see.....I know that the 69 elkys are opposite of the Chevelles as far as vented caps vrs. non-vented. I just can't remember which it is. :clonk:



****EDIT.....69 elkys use a VENTED cap....../EDIT****


But! '68 's are not Vented ---> http://www.chevelles.com/forums/showthread.php?t=109516&referrerid=22275


Pat

But! '68 's are not Vented ---> http://www.chevelles.com/forums/showthread.php?t=109516&referrerid=22275


Pat

Sorry, I think you got some misinformation. I don't think El Caminos got non-vented caps until about 70 or so when they started to use the charcoal canisters for the fuel evaporation system, but then I'm not an expert on those years.
Bruce

Because of the raised/side filler on the El Camino it does not have the same vents as the typical Chevelle. It instead relies on a vented cap for the fuel tank venting. Same thing for the wagon BTW.

This of course changes in 70/71 with the introduction of the evaporative emission controls and charcoal canister.

My '68 does the same smelly thing on right hand turns... even after replacing the cap.

Regarding soldering/welding on the fuel tank... while it is very possible to explode a tank it should also be very possible to take adequate precautions to mitigate the risk. For example a soap and water wash/flush for starters. Secondarily either fill the tank with water while heating or hook up a shop vacuum blowing fresh air through the tank while heating. Either one should make it impossible to explode and I would probably use a combination of both.

One of my other past-times is turning plastic bottles into water rockets. A standard safety practice is to pressure test unusual creations. This process always uses a 100% water fill before pressurizing to control unplanned energy releases. Changes the bang into a poof when they let go.

i have the same problem on my velle..i had no idea it was such a common problem...i have a vented cap and the filler neck is in the back behind the plate...it leaks from the the cap though without a doubt..i was going to try a new cap but that doesnt seem like it worked for anyone else..im stumped

i have the same problem on my velle..i had no idea it was such a common problem...i have a vented cap and the filler neck is in the back behind the plate...it leaks from the the cap though without a doubt..i was going to try a new cap but that doesnt seem like it worked for anyone else..im stumped
The Chevelle should have a non-vented cap. The tanks for the velle had vents up on the front corners.

Apparently nobody had invented "baffles" back then ;)

haha well that may explain my problem..thanks

Funny how these same topics come around every 5 years or so....:D

http://www.chevelles.com/forums/showthread.php?t=58318

Funny how these same topics come around every 5 years or so....:D

http://www.chevelles.com/forums/showthread.php?t=58318

If you read through the above thread. TC member Rich (70 SS 454) says he has a solution for this problem. Are you there Rich? What is the secret fix? Thanks, Scott Hill

If it's only doing it after you fill, could it be expansion. The fuel is cold when you pump it, after sitting in the tank with the car in the sun the cold fuel expands and overflows the filler neck. Use to happen to me all the time with a piece of crap van I had.

Never had the problem with my 67 elky. With the cost of gas I can never afford to fill it completely.

tank was emptied ,aired-out and cleaned before repair.Don't know about grommet inside but i'm not leaking now.

I had that problem on my 66 and replaced the over flow hose. fixed my problem and got better gas milage to boot.

Wow! so many different answers to a common problem!! And I thought I was the only one! My 68 eclo does the same thing - fill the tank in the morning & later that (hot) day find it overflowing past the cap. Turn right & get gas smells. I tried a non vented cap once - after a while, it didn't run very well (loosing fuel pressure). When I removed the cap I got a big hiss & a GONK as the gas tank oil canned back out. So I deal with fuel leaks/smell with a vented cap. SO, if there is a vent in the tank that is plugged, what is it plugged with & how do you unplug it? Does a 68 need a vented cap? I can't imagine this happening all this time since these cars were new...

Your '68 Elky needs a vented cap. That is the only vent you have.

If you wanted to "fix" it, you would need to get into engineering an alternative venting system. For example retrofit the full evaporative emission control system from a '71. Or use a non-vented cap and extend an add-on vent further up in the fender. I suspect that most any single point vent will suffer from slosh. Note that the factory used about 2-3 vent points on the tank combined externally into a "tank" at some height above tank level.

I have considered doing some shopping at the wrecking yard for EEC parts to retrofit in my '68 Elky. The Ford Mustang for example put the charcoal cannister back in the fender and might be a good donor. I have enough 1/4" steel hardline to fabricate the required vacuum line. I may acquire a new tank as part of my EFI conversion and will get a '71 tank if I do so it will have the vent pickups.

same problem - only different here

I have trouble putting the cap on my 67 - doesnt leak - just real tight - very hard to get it on or off - new cap - same problem -

beginning to think somebody replaced the filler neck -

probably just put one from a 68 on my 67 or something like that

Same problem here... I can't believe after all these years we still can't figure out why they leak!! The only thing that has really changed over the years is the refinement process.

My tank is equipped with a vent that is suppose to run up to the fuel pump to the A/C Delco filter. Well, I ripped all that stuff off and put on a better fuel pump and no vent. I think it still smelled like gas back then too.

So, if you want to vent the tank with a newer style fuel pump, where do you run the vent tube now???? It goes out of the tank to the front of the car but I think it's plugged up there because it would leak fuel out of the hose if there was too much fuel in the tank.

I'm tired of the fuel headache, no wonder why it's torn down to nothing right now...

Has anyone figured out a solution to this problem yet? I really don't care about the fuel sloshing out on hard cornering, although that is irritating as well, but I am very concerned about the fuel leaking out when the car is just sitting.

After I fill my car up gas will start leaking out around the gas cap. If the cap is removed it continues leaking/pouring out of the filler tube. It will contine leaking until the weather cools down or until the car begins drawing fuel when it is running. After a couple gallons of fuel are gone it doesn't seem to continue, but I really don't think that filling the fuel take up should cause this to happen.

I work at a high school and people are really getting pissed about the puddle of gas that my car is leaving. For some reason they seem to think it is "dangerous."

I have NO fuel spillage issues from my tank anymore. And I have tried to see if I could overfill the tank to cause problems too.

I put in a 70+ evaporative emission control tank with the extra vents and the extra tank GM put in with the EEC tank. The extra tank sat above the tank and was mostly a way/place to combine the 3 vent lines into a single vent. But it also must have some kind of float in it as it clunked when turned over. Back in the day this combined single line ran up front to the charcoal cannister. In my case it just runs to a clear paper element fuel filter. Maybe someday I will hook up a charcoal cannister...

I also whacked off the end of the fuel filler pipe and replaced it with a modern unleaded fuel filler and sealed cap. Part of the modern filler was a side 1/2" vent line running from the tank back up to a 90* into the filler neck. Since I put this in I no longer have to stand there and hold the gas nozzle into the tank nor have I had any splash out when the tank is full. All around a very good deal as far as I am concerned.

Last winter the solder joint on my 68's filler neck cracked... Leaked gas all over the top of the tank and REEEKED.... Dropped the tank and replaced it with a new one... Problem is gone.

I had used a non-vented cap before, not sure if that caused the crack. When i got the new tank I used vented- no problems for the last year.

If you read through the above thread. TC member Rich (70 SS 454) says he has a solution for this problem. Are you there Rich? What is the secret fix? Thanks, Scott Hill

I'm not sure if I'm the Rich that you are looking for but I've posted about this subject on a number of occasions, so I'll chime in.

El Caminos seem to be much more vunerable to gas tank problems than the Chevelles. Filler neck positioning and venting approach seem to be the culprit. It seems to manifest itself more so in replacement tanks, although original gas tanks are not immune. If you do a search, you'll find a TON of threads on the subject including fumes, leaks, cornering spills, pressue build-up, vacuum build-up and more "expert" opinions on vented gas caps than you ever though existed. There will be more threads and replies than your brain can tollerate in one sitting.

A while back, Widetires22 had the same issues and frustrations that many of us have had or are still experiencing. He did some experimenting and came up with a solution to his problem and the problems that I was experiencing as well. His fix is a modified gas cap. It's easy, it's cheap and I'd be willing to bet that it would solve 90% of the Elky gas tank problems that are out there. He did a nice photo essay on how to modify the cap. Do a search for his thread entitled "Gas Cap Vent Fix".

It's just a temp fix but I stopped the filler neck joint leak with JB Weld until I can get to replacing the entire setup - still holding after many months.

I had the same problem in my 65. I would fill the tank and a day later it would be empty. My fix was a new vent tube running from the tank to the filler neck. some new hose clamps and presto no more gas leak

I'm not sure if I'm the Rich that you are looking for but I've posted about this subject on a number of occasions, so I'll chime in.

El Caminos seem to be much more vunerable to gas tank problems than the Chevelles. Filler neck positioning and venting approach seem to be the culprit. It seems to manifest itself more so in replacement tanks, although original gas tanks are not immune. If you do a search, you'll find a TON of threads on the subject including fumes, leaks, cornering spills, pressue build-up, vacuum build-up and more "expert" opinions on vented gas caps than you ever though existed. There will be more threads and replies than your brain can tollerate in one sitting.

A while back, Widetires22 had the same issues and frustrations that many of us have had or are still experiencing. He did some experimenting and came up with a solution to his problem and the problems that I was experiencing as well. His fix is a modified gas cap. It's easy, it's cheap and I'd be willing to bet that it would solve 90% of the Elky gas tank problems that are out there. He did a nice photo essay on how to modify the cap. Do a search for his thread entitled "Gas Cap Vent Fix".

WOW! Thank you Rich (big white) & Don (widetires22)! That seems to be such a simple fix! I will definitely give it a try!