RT gasoline smell, filler neck leak

[AntonLargiader]

I have a 2014 RT in the shop that had a persistent gas smell on the test ride. Turned out the filler neck assembly was not sealing to the tank at the front. The top of the plastic tank is flat, and there's a rubber gasket on the bottom of the filler neck that seals to the tank. The front of the tank opening had a low spot that allowed a gap between the parts. I could see a rub mark there, as if something in the past had been pushing on that area so I bought a used tank, but the used tank is even worse in this way.

It looks like a bad design. The bolt circle is 4" diameter, but the gasket contacts a circle less than 2.5", so it's pushing down on unsupported plastic. There's nothing keeping that plastic flat enough to maintain a consistent seal against the lip of that rubber gasket (which is less than 1mm tall). Given the condition of the used tank I bought, I have to think that there are a lot of bikes out there with this issue. If you have a persistent gas smell from your wethead, it's easy enough to check this... make some sort of plug for the internal part of the filler neck with a tube in it, and lightly pressurize the tank by blowing into it. If it's leaking at the front, you will know.

This shows the depression between the threaded inserts at the front of the tank:


That low spot continues all the way back to the opening; you can see where the gasket touches. It's very easy to feel the low spot running a finger around it, but you can see it clearly with a straight edge also. There's no expectation that a 1mm tall rubber lip is going to seal this off.


As an interim repair, I have built this area up (on the original tank; the pictured one is the used one I bought) with a few coats of sealant but it may not prove to be a long-term solution.

I'm curious about other tanks out there; do they have this same low spot and leak, or are they OK?

 

[Geekmaster]

I had the same exact problem on my 2014 RT too. Yours may be a little more warped than mine, though. I used some Permatex gasket sealant that was rated for oil/gasoline. I followed all the instructions to the letter, ensuring that the sealant was all around the opening where the gasket was positioned. I then put the gas cap assembly back on, and was discouraged because it still leaked. However, I then tightened the screws a little more and waited overnight. In the morning, no more gas smell or leakage. It was easy to test by rocking the bike back and forth. Just one caution ... I've heard it's easy to loosen up the brass inserts in the plastic tank if you tighten the screws too much.

Once I fixed it, I'm now a bit paranoid about putting on any tank bags that bolt to the tank ring, though.

 

[61249]

Thank you for the insight, my 2014 RT has had a lingering gasoline smell for years, especially when I top off the tank.
I will check out the filler gasket situation and apply the fix and hopefully eliminate the gas odor.

 

[ldhardy12]

Looks like I'm also on the warped/leaking gas tank team.

BMW is not feeling like they need to address this design flaw. You're on your own for this. I also found out that they did NOT redesign the tank. Is this the case with subsequent years RT's?

Love to know if this is all of the years of production. I submitted my concern on the NHTSA web page along with the VIN. Maybe if they hear from a few more of us BMW would come to the plate.

 

[PGlaves]

I submitted my concern on the NHTSA web page along with the VIN. Maybe if they hear from a few more of us BMW would come to the plate.

I hope that isn't wishful thinking. More than 100 complaints about failing final drives on K1200LTs didn't cause any action because nobody had died yet.

 

[omega man]

Another thread discussing the similar problem-

R1200RT warped fuel tank

I have a 2014 R1200RT that has a warped gas tank near the fuel cap. The plastic is so out of shape that a new tank is required and the cost of this replacement is very steep. Very Steep. I contacted my dealer and was told there are no recalls for this although there is a new part number of...

forums.bmwmoa.org

OM

 

[ldhardy12]

I hope that isn't wishful thinking. More than 100 complaints about failing final drives on K1200LTs didn't cause any action because nobody had died yet.

Me too. I had hoped that leaking fuel would be more of an issue with BMW. Something about fire hazards might have brought them to the table. I have a 2005 Harley Road Glide with 117,000 miles on it that has not had this level of problems.

Having 4 driveshafts, a shock recall and now this fuel tank leak would make me hesitant to recommend one to anyone.

I have owned many different bikes in the years I've been riding and have ridden through Canada, Europe and the US so this isn't the first bike I've owned and understand that bikes do require more maintenance than cars. It just seems that this RT requires more attention than I ever thought a bike should need.

The Bring More Wampum moniker that BMW has is valid.

 

[rhbike]

Is there any opportunity to insert a dowel or other suitable material inside the tank that is wedged between the bottom of the tank the top of the tank, to force the sunken part of the tank back into its proper position? I'm thinking of a rod that would be left in place. It would certainly be a heck of a lot cheaper a solution than a new tank.

 

[omega man]

I would like to see if a brand new tank was substantially different.
OM

 

[ldhardy12]

I would like to see if a brand new tank was substantially different.
OM

It is the same tank. There is not a new p/n for this tank and it is the same p/n for all the years of manufacture. I asked if the RT-P version is the same as ours and it is the same. The reason that they have not replaced any of the police tanks is that those only see 5-6 years of service. The dealer's guess was that this deterioration is based on years, not miles and that may explain why the RT-P hasn't seen this since they aren't used as long as ours.

 

[omega man]

What if a new tank has the same “dip” as yours and the design is to have the (new) gasket make up for any irregularities? That’s why I wondered what a comparison between your tank and a new tank.
OM

 

[ldhardy12]

Before I do the route of the new tank, I would check the replacement tank for any irregularity in the surface of the new tank. According to the dealer the replacement tank(s) they've installed are flat, not dipped.

 

[omega man]

I don’t think I would purchase a new tank especially if this is a common problem. I would make a thicker gasket or stack OEM gaskets to seal the void. I would purchase some gasket material that is gasoline resistant and ride on.
Example here- https://www.henniggasket.com/gasket...t Gasket,resists compression set and abrasion.
OM

 

[ldhardy12]

Thanks for sharing the link to this company. I think this is the best way to move forward instead of replacing the old tank with a new one.

BMW Motorrad called me to let me know that they would not provide any assistance for a replacement tank. They said that if(?) there is a recall or bulletin for this tank and I replace it, to keep my receipt for reimbursement at a later date. Should I hold my breath?

 

[omega man]

That was an example of gasoline resistant material. There are a number of suppliers for this type of material.
I have stacked a number of gaskets or used a non-OEM gasket that I made myself to compensate for situations that happen.
Gaskets can be compressed beyond specifications due to age and original installation resulting in what you describe. I think making your own cure will serve you well.
OM

 

[PGlaves]

Should I hold my breath?

Nope!

 

[r0ckrat]

Should I hold my breath?

Only if you don't want to smell gasoline?

 

[ldhardy12]

Only if you don't want to smell gasoline?

Touché

 

[robsryder]

It would seem straightforward to address the non uniform surface using some fuel resistant epoxy to fill in the gap shown in Anton's photos. The grey JB Weld epoxy comes to mind as a potential candidate. I know that I would not wait around for BMW corporate to propose a fix.

 

[robsryder]

Following is a link to a website which gives some guidance on repair of plastic gasoline fuel tanks -

3 Best Epoxy For Plastic Gas Tank Repair (With Comparison) – Sticky Aide

www.stickyaide.com