Leaking gas cap.

Mick

New member
My gas cap is leaking on my 2011 EC300, basically leaked since it was new, I only have 14 hours on it now....I bought another cap from gofasters, that is leaking as well...perhaps a defective tank (?), or can I file down the top of the filler neck? Should I go through my dealer or the GG distributor, if it is a defective tank before I try to file down the filler neck?

Anyone else have this issue?
 
My gas cap is leaking on my 2011 EC300, basically leaked since it was new, I only have 14 hours on it now....I bought another cap from gofasters, that is leaking as well...perhaps a defective tank (?), or can I file down the top of the filler neck? Should I go through my dealer or the GG distributor, if it is a defective tank before I try to file down the filler neck?

Anyone else have this issue?

Never heard of it ;)

... ok, maybe just once or twice.

There are a couple things you can try -

1) filing/flattening the tank filler lip is one, if you are careful and prevent the shavings from dropping in.
2) installing a different sealing ring. If you look in your present cap you can see a witness mark of how the present ring contacts (or doesn't). Several guys bought fuel-resistant rubber and cut their own gaskets, or you can try Atlantic Powersports (?) part, seachable in another thread. I had more luck with the gasket I cut on my own, but your results may vary
3) get the new style cap. After replacing two or three for customers the last one I got from Go-Fasters is a new design. PM me if you want to buy it.
 
It came with the newer cap, the one with the check valve in the cap itself, correct?

The one I order has an external check valve...that one is leaking worse than the original.

As for filing, I was going to pull the tank, petcock, so I can clean it out if I got shavings in it. Which is highly likely!

I'll try making my own gasket first. Looking closer at the filler neck, there is a slight dent in it. Seems like there are a lot of air bubbles in the plastic at that section...assuming the dent is where an air bubble was...or something...:p
 
The inner seals shrink over time. I've gone through 3 caps on my 2010. One replaced under warranty. Tried fixing the second one with a custom gasket but issues cutting to shape correctly and then the fuel ate away at the rubber even though the shop told me it would be okay with fuels. *shrugs*. The new one is still in its packet. I have been using the cap without any gasket/rubber insert and it still seals well. I can lay the bike over or rock it on its suspension with a full tank without any spilling out so thats good enough for me. When the seal starts going its very obvious.

Haven't seen or heard anything about the new style cap. I priced an after market but at $115 or whatever price it was I thought feck taht!
 
I don't think filing it down is going to work, look at all those air bubbles, it anything it will make it worse.

The cap pictures, the one on the left is what came with the bike. I think it is more of a tank issue than the cap.

431506_10150563525549630_766319629_8811781_1472685372_n.jpg


420231_10150563543264630_766319629_8811793_548205034_n.jpg
 
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I don't think filing it down is going to work, look at all those air bubbles, it anything it will make it worse.

431506_10150563525549630_766319629_8811781_1472685372_n.jpg

With that filler neck I'm not surprised it leaks. I shaved one flat with a razor blade but with all those dimples on the current (non)sealing surface you may not get to flat before you bottom out on the outer edges without sealing in the center.

What about dipping some two-part epoxy or something similar and then filing and sanding that flat?
 
I am going to try and find a soft o-ring first.

That and I am going ask my dealer about warrantying it, since it looks like it is a bad molding job.
 
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I got the fix from Atlantic Powersports. Installed for 6+ months with no leak. It's only $5. Save yourself time and hastle and order from them. Search the forum to find ordering instructions.
 
That is the crapiest looking filler neck I've ever seen. I doubt any gasket is soft enough to seal it. The notch in the top surface at 9:00 in your picture is too deep.

I use a flat metal block and wrap it with coarse waterpaper. Yours is bad enough I would start with emery cloth to rough off the top first. Go progressively finer with the waterpaper until you are at 400 grit. The tank needs to be off the bike for this much sanding. It is critical that you don't rock the metal block as you go.

Those pores in the plastic are usually small enough that once the neck is flat, the gasket will close them off. It will take a few hours to do this. You may need a thicker gasket when you are done.

Try for warranty on that tank first.
 
Thanks for the advice, I dropped my dealer an email...gonna wait see what happens, before I touch it.
 
Thanks for the advice, I dropped my dealer an email...gonna wait see what happens, before I touch it.

Try it with the gas cap on the left without the rubber insert installed. It'll take all of 2 mins to try and I bet it reduces the leaking significantly.
 
Just try it on the stand with a full tank. Rock the bike around on the suspension. Lay it over on its side a bit. It'll be evident how bad its going to leak right from the get go.

Mine leaked really badly with both a shrunk inner seal, and again with a home made gasket (sealed well for a while until it shrunk down too). I'm actually shocked how well it appears to seal with no gasket. I wouldn't have imagined it working but it has.
 
I got the fix from Atlantic Powersports. Installed for 6+ months with no leak. It's only $5. Save yourself time and hastle and order from them. Search the forum to find ordering instructions.

Yep, bought a batch of them. I still get some weeping, so I think that I am going to try and double up!
 
my tank looks like that too, air bubbles in the plastic, and it leaks unless I tighten it really tight

it's a lesson I have to relearn every other time I ride
 
Fixed it, found an o-ring that works. must have a bit more give than a flat rubber washer.

Just something I found at the hardware store, I don't know if it is fuel safe, time will tell.
 
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Well that didn't work...o-ring must of not been fuel proof...it swelled pretty bad, but I think I am on the right track. Going to see if the local o-ring supply house has some fuel proof ones.
 
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