'92 K75 Fuel Cap O-Ring Size

[bdogchicago]

Anyone happen to know the official size of the fuel filler cap blue o ring? Specifically the one that sits on the key housing - https://photos.app.goo.gl/QhktRUSXuDcAP5Nt7. I was surprised to find it missing - while cleaning up the tank before remounting. I'm guessing it was lost when the PO had the new fuel pump installed. Trying to avoid purchasing an entire new gasket set (16 11 9 062 461 GASKET SET) as everything else is in good condition. Based on my measurements it appears to be .75" ID, 1" OD. Planning to drop in a simple rubber O-ring from the local hardware store; e.g. Danco 1" x 3/4" O-Ring (#15).

Also, any tips on removing the screws holding the filler cap receiver on the tank; e.g. the ones inside the tank - https://photos.app.goo.gl/UujQYUr4aujATbnx5. They're pretty rusted as to be expected so thought it best to replace. Using a screwdriver in that space is a bit tight particularly for rusted bolts.

Finally, I want to clean the lip of the fuel tank as the previous gasket seems to have deteriorated and left a crust. Again, thinking it's best to clean everything now.

Thanks.

[Laitch]

I don't know what that screw is all about but it might be an attempted solution of a previous owner's problem—mental or mechanical. The filler cap "receiver" isn't a offered as a separate part. You can clean off that screw with a Scotchbrite pad it's bothering you; just don't let a cleaning obsession snarl your life. Clean up the cap gasket surface with a Scotchbrite pad before reassembly.  In 80,000 miles, I have redone the fuel cap gaskets with the kit only once, at 60,000 miles. If one of your assembly's gaskets is missing, installing the entire kit into your cap might be appropriate for the long term; otherwise, you'll probably need to measure the space if nobody drops by here to help you. Use a fuel-resistant Viton o-ring.

Here's a photo of the underside of that assembly. You won't see a screw like the one you're indicating.

[The Mighty Gryphon]

How does someone who is trying to stay outside of Alphabet's surveillance system view the photos you want us to look at?

[Laitch]

How does someone who is trying to stay outside of Alphabet's surveillance system view the photos you want us to look at?

Wearing a Danco Universal Defender decoder o-ring helps.

[The Mighty Gryphon]

Or maybe the poster can use Attachments and other options.

[bdogchicago]

Laitch thanks for the detail response and advice. I'll see if I can get a Viton o-ring that will fit. I hear ya regarding the full kit but at some point I will likely need to repaint the tank and bike as a whole (some body part damage) and can replace the full kit then. My comments regarding the inner screws are less asthetics and more contamination related. I was worried this would continue to deteriorate and dirty the fuel, cause additonal flash rusting/corrsion, etc. I'll give them the scotbrite treatment and call it a day.

The Mighty Gryphon,

I hear ya regarding the link issue. I thought anyone could access the link regardless of whether they had a gmail. Not trying to convert anyone, just taking the quickest route - all my photos are in the cloud. Noted for the future.

[Laitch]

My comments regarding the inner screws are less asthetics and more contamination related. I was worried this would continue to deteriorate and dirty the fuel, cause additonal flash rusting/corrsion, etc.

I don't know what those screws are doing there, bdog. They aren't indicated in any fiche I've seen yet. Hold a mirror down in that hole then with your second and third hands, take a photo of them and post it here.

[bdogchicago]

Will try to get better photos when back. Currently on the road, with the fam, not the K75.

[bdogchicago]

I'm all set. I purchased a Danco 1" x 3/4" O-Ring (#15) from Menards. It's not nitrile rubber so not a long term solution but will work for the season. Thanks again.

[bdogchicago]

Note: I found the details regarding the screws holding the filler cap receiver on the tank; e.g. the ones inside the tank. They're self tapping screws, M4X8, part number 07119918519.

[Laitch]

Thanks for the update. It still isn't clear to me why that screw is there in your moto. The screws you've indicated attach the flapper assembly to the cap assembly. The collar onto which the cap assembly mounts is brazed onto the tank.

Part 07119918519 in its natural habitat.


Here's a photo of the inside of a late model tank. There are no screws fastened into the interior side of that collar.

[beemuker]

I’m in the process of cleaning my tank and replacing the pump is there any reason to reattach the flapper assembly my screws were all rusted and a bitch to get out I don’t really see a reason for the flapper, but it’s there so must be there for a reason

[The Mighty Gryphon]

I could be mistaken, but those flappers were an EPA thing to prevent use of leaded fuel.  Back in the day when both were still available, the unleaded fuel nozzles were a smaller diameter than the regular leaded fuel nozzles.  Obviously, you wouldn't be able to get the leaded nozzle into the tank.

Since leaded fuel isn't readily available anymore, the flapper's only real purpose is to prevent splashing fuel and overfilling the tank.  Removing it lets you get an extra 10 miles worth of fuel in the tank and see how much fuel is in there.  I've removed it from all of my bikes.

On the plus side, it will prevent you from accidentally dropping your keys in the tank.

[beemuker]

I could be mistaken, but those flappers were an EPA thing to prevent use of leaded fuel.  Back in the day when both were still available, the unleaded fuel nozzles were a smaller diameter than the regular leaded fuel nozzles.  Obviously, you wouldn't be able to get the leaded nozzle into the tank.

Since leaded fuel isn't readily available anymore, the flapper's only real purpose is to prevent splashing fuel and overfilling the tank.  Removing it lets you get an extra 10 miles worth of fuel in the tank and see how much fuel is in there.  I've removed it from all of my bikes.

On the plus side, it will prevent you from accidentally dropping your keys in the tank.

thanks that’s what I thought