Fuel smell

[GreatDaysAhead]

I think I smell a light fuel smell at stops after riding a bit. Can't seem to locate source for sure but think it is from fuel pump/line area. Checked for visible leaks but have found none. Nothing dripping nor moist. 2008 R1200RT. Any ideas?

 

[JFab]

I'm coming from a K1200LT but I would check your quick connect O-rings to make sure they are in good shape.

 

Have replacements on hand before you separate them.

 

Good luck.

 

Joe

[BOOCH]

If you go back 7 pages to 05/18,you will see a post regarding a fuel leak. I would hate to think that a 2008 could have this problem.

Steve

[wiskers]

If it only makes the smell when you stop and start and you can see no visible signs of external gasoline leakage with the engine running look closely at your gas cap sealing area. The rubber sealing gasket is pushed down by some sort of spring seat affair that can stick in the semi retracted position. My 1200RT did the same thing as I was getting a gasoline smell only when stopping or accelerating hard.

It was a difficult thing to find just by looking at the cap and tank filler area.

To find my leaking cap I actually disconnected the tank vent hose connector near the glove box area then hooked up a short length of hose then used my mouth to blow air into the tank vent hose. I could hear a definite hissing of air escaping at the cap area as I blew air into the tank.

Once I found the cap leaking problem I twisted and pulled down on the rubber gasket and tin seat above it. That temporarily stopped the gasoline smell but it will take a new cap to permanently cure the problem as when I pull and twist on the gasket it only stops the smell for a while then the darn thing sticks up again. I see there is now a superseded cap in the parts diagram so maybe BMW is aware of this issue. If it is your fuel cap leaking be prepared to positively demonstrate to your dealer that the cap is the problem as most dealers will first deny you have a problem, then try to convince you that it is normal, then spend many minutes telling you why you know nothing and don’t under complex BMW motorcycles.

Wis

 

[bobbybob]

If it only makes the smell when you stop and start and you can see no visible signs of external gasoline leakage with the engine running look closely at your gas cap sealing area. The rubber sealing gasket is pushed down by some sort of spring seat affair that can stick in the semi retracted position. My 1200RT did the same thing as I was getting a gasoline smell only when stopping or accelerating hard.

It was a difficult thing to find just by looking at the cap and tank filler area.

To find my leaking cap I actually disconnected the tank vent hose connector near the glove box area then hooked up a short length of hose then used my mouth to blow air into the tank vent hose. I could hear a definite hissing of air escaping at the cap area as I blew air into the tank.

Once I found the cap leaking problem I twisted and pulled down on the rubber gasket and tin seat above it. That temporarily stopped the gasoline smell but it will take a new cap to permanently cure the problem as when I pull and twist on the gasket it only stops the smell for a while then the darn thing sticks up again. I see there is now a superseded cap in the parts diagram so maybe BMW is aware of this issue. If it is your fuel cap leaking be prepared to positively demonstrate to your dealer that the cap is the problem as most dealers will first deny you have a problem, then try to convince you that it is normal, then spend many minutes telling you why you know nothing and don’t under complex BMW motorcycles.

Wis

 

They must have changed the cap in 08; my 07 doesn't seem to have a *movable* rubber gasket. It is held against the filler opening by the cap's pressure. Can you be a little more specific as to what you see on your gas cap's apparatus?

 

Edit: Oops I see you have an 05, not 08 as the OP has. Still wonder about the cap differences...

[wiskers]

Yes there seems to be some things changed in the 2006-2008 range. The tank now has a plastic filler neck in the top and the cap sealing area does look slightly different.

Not sure I can explain my 2008 cap but the part that actually seals to the plastic filler neck is a rubber gasket supported by a tin or metallic disc that is somehow spring loaded. I can’t see up inside above the metallic disc so can’t say how the springiness is produced or captured. There is just enough give in the gasket support pieces that it allows the cap seal to maintain a positive seal on top of the tank filler neck if it is working correctly.

 

[Bronx Cheer]

I have the same issue with my 08. I had the dealer replace the fuel cap but the problem still exists. It has gotten better over the Winter, but the fumes come and go. I noticed on the 09s the filler cap is completely different. I believe BMW had a problem and corrected it. Check out a 09 filler cap, you will see it is different.

[GreatDaysAhead]

Are the disconnect o/rings avail from BMW? I did'nt see them on the parts fiche. Does anyone know if the fuel filler bolts go into a blind hole or do they possibly protrude into tank? I installed a Bags Connection tank bag filler mount quite ahwile ago.

[Don_Eilenberger]

The quick disconnect O rings are standard "011" O-rings. From places like McMasters-Carr, about $0.10/each. I bought 100 for something like $10, and gave most away to friends for spares. You want Viton - it's fuel resistant.

[timboaz]

I am having the same problem with my 08 recently. Took to the dealer, they checkd the quick disconnect and no leaks there. Seems to me to be around the gas cap which they looked at but the problem wasn't solved.

 

[EddyQ]

This may be far to obvious, but, are you sure you are closing the cap all the way? Several times I've gotten a gas smell and found my cap was closed, but not all the way. It needs to click shut.