Petrol smell

[Cobbster]

Hi all,

The past couple of outings have seen me return well into the reserve ie, green light on. After I put the bike in the garage I've noticed a strong smell of petrol. Last night I looked around but could'nt find anything but tonight I discovered a small dribble of petrol coming out of one of the hoses situated behind the rear brake peddle. I know these are the breather and overflow hoses for the tank but could'nt tell you which is which. Also, one of the hoses seems clear and the other blocked off. If I blow gently into the one that is dribbling fuel, its clear and I can hear my breath going into the tank. The other is blocked and I can't blow through it.

Any thoughts or experiences.

Thanks, Cobbster

[bigblackfalco]

The other one that you are trying to breath through is the battery breather.
I'd give that one up quickly!

[timbox2]

Yeah, I sometimes get the same thing, Id love to know the consensus.

[Cobbster]

Hi,
I only have two hoses sticking out the back and both definitly connect the the fuel tank. I don't know if my 2003 model was built without a battery breather or if its been taken off but theres nothing connected to it.

Thanks, cobbster

[Boxadog 2000]

Funny that cos my GS also smells of fuel when I put it on the side stand when the tank is low.

Bob

[chobbler]

We get the same thing on our family's BMs. I think it's that "colostomy bladder" in the tank letting go every now and then.
Nothing to get worried about...probably.

[oyster]

Three breather hoses = 1. battery breather, absent on gel battery (or just missing) 2. tank overflow - under filler cap, hole punched in the upper, outer filler neck ring is connected to this 3. tank breather, vents the upper most bulge in the tank via the black foam block.
So a couple of things possible, tank filler cap is letting by on 'good, serious' riding so fuel dribbles out the overflow; or similar from the breather?

[Cobbster]

Hi chaps,

I find it confusing that I should get spillage from either hose when theres only about 4lt of fuel in the tank. It only happens after riding and when it has stood for a short while. After being left overnight theres no dribbles and no petrol smell.
I'm also confused why one hose should be clear and the other is a dead end. The clear one must vent into the tank because I can hear it when I blow down it so I assume that one goes to the internal foam block.

I'm going to drain and remove the tank tomorrow, I'll probably replace the fuel filter while I'm at it. Which leads no another question, can I drain the tank via the loop hose that runs under the tank? ie, pull it off and let fuel run into a can.

Thanks, cobbster

[oyster]

I'm going to drain and remove the tank tomorrow, I'll probably replace the fuel filter while I'm at it. Which leads no another question, can I drain the tank via the loop hose that runs under the tank? ie, pull it off and let fuel run into a can.

Yes

[snavetrauts]

Cobbster.... You might consider fitting the "Quick release" male and female connectors to the two fuel lines... as per the 1150's (I think).. I have done this as a result of a previous thread on here and am very pleased.

I biught them from Motorworks... quite expensive....but worth it.

Stuart

[Cobbster]

Hi snavetrauts,

I liberated a couple of gate clamps from my lab a while back in preparation to taking the tank off at some time. I'll use them this time round but the quick release connectors are definitly the way to go in the future. I believe the filter clamps are one use only jobs so I'll have to order some re-useable ones when I order the filter.

I'll keep you all posted about what I discover post strip down.

Cheers, cobbster

[Cobbster]

OK had a bit rummidge and tinker this afternoon. What I found was the blocked hose was the overflow. A squirt of WD40 and a poke with a bit wire cleared it. The clear hose was the breather connected to a black plastic contraption in the top of the tank. I took it for a spin, still on reserve, and came back. Left it a while and, yes you guesed it, it dribbled from the breather. Prior to dribbling I could see vapour coming out.

Theory time. I think theres nothing wrong with the setup, ie, hoses are connected where they should be and working ok. The dribble is a build up of vapour which is due to a large area of 'empiness' in the tank. The less fuel in it the greater volume of vapour is allowed to build up.If there were more fuel in it then you'd get a lower amount of vapour building up in the head space and making its way down the breather hose. Theory over.

Shoot it to bits if you want to lads 'n' lasses, its the best I can come up with. Remedy, keep more petrol in the bugger.

Cheers, cobbster.