Topic: Jaz fuel cell cap gaskets

We've struggled over the years with the ring gasket in the Jaz cell caps swelling due to ethanol. Once they start to swell they won't fit in the bail handle cap. It's kept us off track while we scramble to find or make a new one.

After getting hosed again by this over the weekend at The Ridge I called Jaz up for a solution. They offered to send me free replacement cork gaskets. We'll see if they hold up, but at least they're free.

Of course the support rep offered to sell me replacement bolt-in fill plates to switch to remote fill or their billet cap at some kind of one-time only discount. But the bail handle caps work for us if we can only find a material that can resist ethanol. Getting ethanol-free gas is also an option but the logisitics and cost make it a hassle I'd like to not have deal with.

Anyone experience this and found a solution? Any experience with a cork gasket? If you have this type of cell/cap you can call Jaz for a freebee (she agreed to send me 4 for our 2 cells, no proof of purchase requested).

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Re: Jaz fuel cell cap gaskets

Yes, I had the same problem several years ago. The fuel swells the sealing gasket on the cap and it won't stay in the cap and when we would go to twist it back on it would partially pop out and not seal.

What we did for the short term was stretch a sacrificial harbor freight blue nitrile glove over the tank neck opening before screwing the D-handle cap down onto the cell. It would tear the glove, but still protect the sealing ring.

I did message JAZ and they sent me some new rubber gaskets for free. Oh, wait, here's the email exchange. It was in 2011. Wow, just a minute ago...

For the record, the newly supplied neck gaskets solved the problem and they did not swell.

Here is the copy-paste of my email echange




Hi Mike,

Must of been from a bad batch if the nitrile glove works fine. We will send a couple cap gaskets in the mail. Hope this fixes the swelling issues. Let me know.

Thanks,

B*** @ JAZ Products




    ----- Original Message -----
    From: Mike
    To: B****
    Sent: Wednesday, November 23, 2011 10:08
    Subject: Re: Fuel filler cap seal

    I appreciate the response,

    Interesting you say the supplied gasket is made of nitrile. I've found that if I stretch a cheap Harbor Freight blue nitrile glove over the filler neck before I put on the cap (sacrificing the glove as it tears when cap removed) the seal will not swell nor will the glove become altered from the fuel contact. Not an ideal solution since there's the risk of particles falling into the cell and clogging the pickup.

    It could be that I did get a seal from a bad batch.

    I will happily accept your offer of a replacement seal from a more recent batch.

    My shipping information:
    Mike ***

    And thank you for the suggestions.

    Regards,
    --Mike


    --- On Wed, 11/23/11, B****@jazproducts.com> wrote:


        From: B****@jazproducts.com>
        Subject: Re: Fuel filler cap seal
        To: "Mike >
        Date: Wednesday, November 23, 2011, 9:58 AM

        The blend of fuels can cause issues with the gasket as they are normally made for one type of fuel and not blended fuels.
         
        The material is a Nitrile rubber (Buna-N), which is a fuel resistant high quality seal. The problem is with the fuel nowadays and not the gasket itself. A lot of gas stations are using Ethanol/Methanol blends which will attack the gasket after some time.
         
        I would recommend buying a 8-1/2" x 11" sheet of fuel approved cork gasket material at a local auto store. Cut out a gasket to match ours and give that a try.
         
        Other than this, you can have a few cap gaskets on hand and rotate them out. As you said, once they dry it goes back to its normal size. It may be that the gasket you have could be from a bad batch. I can send you a couple at no charge if you would like.
         
        Hope this helps. Let me know.
         
        Thanks,
         
        B*** @ JAZ Products
         
         

            ----- Original Message -----
            From: Mike
            To: info@jazproducts.com
            Sent: Friday, October 14, 2011 21:09
            Subject: Fuel filler cap seal

            I purchased a Jaz fuel cell through amazon.com and it was drop-shipped direct from Jaz. I have had problems with the filler cap seal as it will swell and become oversized during use and will not longer seal causing raw fuel to spill into the trunk and passenger compartment. This was VERY pronounced when I was using a blend of traditional "pump" 92 octane fuel and 100 octane unleaded fuel, but still happened when I used only 92 octane pump gasoline. I compete in an endurance series which requires up to 24 hours of continuous driving and fuel spills are not tolerated. I need to know if I were to purchase replacement part BAIL HANDLE CAP GASKET 850-300-01 if that will suffer the same fate or is this a superior material to that which is supplied with the cap when the cell is purchased.  I have used the cell only 3 times and the gasket has swollen on each occasion after about 3-4 hours of use. After it is removed and left for a couple of days, it will shrink back down and seal again.

            Thank you for any help you can offer to help restore my faith in your "safety" equipment.

            --Mike

3 (edited by Brett85p 2020-07-30 01:39 PM)

Re: Jaz fuel cell cap gaskets

I started duct taping a spare gasket in a ziplock bag to the fuel cell so when they fail you can quickly swap in a new one.
They gaskets are consumables in my opinion

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Re: Jaz fuel cell cap gaskets

Cork? What is this 1916?

Mistake By The Lake Racing (MBTL)
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Re: Jaz fuel cell cap gaskets

Guildenstern wrote:

Cork? What is this 1916?

No, 1991 in England.

Re: Jaz fuel cell cap gaskets

With the exchange rate, same difference.

Mistake By The Lake Racing (MBTL)
88 Thunderbird "THUNDERBIRDS ARE GO!", Ex Astris, Rubigo / Semper Fracti
A&D: 2014 Sebrings at Sebring (NSF), 2014 NJMP2 Jurassic Park (SpeedyCop), 2012 Summit Point J30 (PiNuts)
2018 Route Sucky-Suck Rally Miata, 2019 World Tour Of Texas 64 Newport

Re: Jaz fuel cell cap gaskets

Do you have a picture of what the gasket looks like?

Our non-Jaz fuel cell came with a round O-ring in the bottom of the screw on cap. After over tightening the cap once and having to fish the o-ring off of the foam we changed to a Viton square profile o-ring from McMaster. Cheap, effective, compatible with gasoline and ethanol.

Re: Jaz fuel cell cap gaskets

I use these caps and cork gaskets solve this problem. They will change shape over time but it's years not minutes.

Prior to cork gaskets, I had a couple spare caps and would swap caps during fill ups.

Troy

#35 LRE
1973 Datsun 240Z