Fuel pump leakage from third tube?

[LuchikaDeSousa]

Hello everybody,

I'm on this forum even if I'm searching information about my father in law R1200GS STD 2008 because we figured out that his bike is mounting a R1200RT 2010 fuel pump which has run into some sort of problem some days ago.

After filling completely the fuel tank at the gas station and starting the engine, the pump started "to spit out" a lot of fuel from the hose connection you see marked in green in the picture below.

IMG_20240124_223005.jpg (206.75 KiB) Viewed 3677 times

On his bike, that hose connection is completely disconnected (no tubings present at all!) and we are trying to figure out what is the purpose of this third tube on R1200RT, to then try to understand what has gone wrong and how to fix the problem definitively.

Thanks in advance for your help, hope this is not a duplicate!

[LuchikaDeSousa]

Nobody?

[David.]

Have I understood this correctly, the bike in question is a 2008 (Hexhead) GS fitted with a 2010 (Camhead) RT fuel pump.

From both the Hexhead and Camhead Haynes manuals, it "appears" that the GS fuel pump does not have the third hose connection. On the RT, this connection is described for both Hexhead and Camhead as a fuel tank drain hose. Perhaps an RT fuel pump should not be fitted to a GS.

[LuchikaDeSousa]

Thanks David for your kindly reply.

Unfortunately the RT pump has been fitted on this GS in 2013 by BMW service, and until 2024 it worked flawlessly.

We experienced a fuel leak for the first time some week ago, so now we're just trying to figure out what happened and where this third hose is expected to be connected on a RT, if it's draining on the floor or if it's returning back in the fuel thank, or whatever.

[David.]

On my 2012 Camhead RT, the third hose drains to the floor.

[LuchikaDeSousa]

Thanks again, this was the information I was looking for!
As far as you know, is this third tube passing near the fuel tank cap before going down to the center stand of the bike? In other words, does it need to be treated like a communicating vessel and go upwards first then down to the floor, or doesn't matter?

[LuchikaDeSousa]

IMG_20240131_080112.jpg (203.89 KiB) Viewed 3502 times

From this picture it looks like it is going straight to the floor without further precautions, can you confirm?

[David.]

The third tube passes beneath the fuel tank, there is a tube connector on the side of the air box, from there it continues to ground near the centre stand.

[Rosieposie]

I know this thread has been dead for a while, but I'm finding it interesting because I have a BMW R1200RT from '08 with a fuel leak at that quick release connector to the fuel pump. Funnily enough I'm facing a different problem, where I was replacing the whole qd but it snapped clean off as soon as I applied a spanner to it. And I've bought the Hayes manual and still can't work out why my fuel pump has two quick release connectors attached!

Looking at the schematics on the Hayes manual, it seems like I should have another pump on the right wing of the tank, presumably to pump fuel to the other side. But I took everything off yesterday and I just ... Don't. My fuel tank on the other side doesn't visibly have anything else to it (granted; I didn't completely remove the storage compartment. But I looked around it through the gaps... Nothing like what I see on YouTube videos!).

Could anyone explain to me, how fuel actually gets from the right side of my fuel tank to the left? On my motorcycle, as in the pictures on this thread, there is a rubber hose attached to that green arrowed nipple shown above. But in my case this came off by accident and appeared to be broken inside the hose. So now I'm wondering if I need to fix that, too...

[David.]

Looking at the Haynes Manual #4598 for BMW R1200 Twins '04 to '06, there is a photo (2.15) on page 3.4.

From what I can see, the two quick release connectors are the fuel delivery and return hoses.

The "rubber hose attached to that green arrowed nipple shown above", is the fuel tank drain hose.

There is only one fuel pump on the left-hand side of the tank.

[Rosieposie]

Hi David,

Thanks for your response. I'm afraid I'm a bit of a newbie, both to BMW ownership and to basic maintenance... I bought my bike used a couple of weeks ago and on basic inspection it looked good. When I drove it home I did notice a fuel leak - hence the picture, where I attempted to replace the culprit, which I found to be the quick release mechanism on the fuel delivery hose...

The manual reference you gave was super useful, thank you. I think I got confused reading a section on the GS instead of the RT, but I'm much happier knowing this is a standard part for this bike!

Unfortunately in my case, seems like the fuel tank drain outlet has snapped in half and completely corroded. Do you reckon this warrants a fuel pump replacement? They are quite expensive so I'd rather see if there's anything else I can do first... Literally as soon as I started working on my fuel leak, I noticed the rubber hose attached to this bit just popped right off. Maybe it's not even a problem, but I've only just ridden the bike home for about 150 miles and only then spotted the leak, with the tank always being less than half full.

Thanks again for your help

[David.]

What is your location.

[Rosieposie]

Hi David,

I'm based in the UK - for some reason I've struggled to find 'United Kingdom' on this website to set as my flag...

[Stu]

Hi David,

I'm based in the UK - for some reason I've struggled to find 'United Kingdom' on this website to set as my flag...

Great Britain

I have set it for you

[David.]

Do you reckon this warrants a fuel pump replacement, they are quite expensive.

Try Motorworks for a used fuel pump.