Fuel Level Indicator

[marcopol]

Just changed over tanks and I obviously did something wrong in the process of putting the guts back in place as I am getting no reading on the fuel level indicator. Real pain in the ass of a job and I now suspect the float is trapped. Will have to redo the whole bloddy job again. The float and all the mechanism that it is attached to can only face backwards, correct ?, I am 99% sure (followed as per the schematics on the BMW workshop manual)that the two internal tubes in the tank are connected to the correct pipes on the black circular thingy that holds the pump and filter. Maybe one of the pipes is trapping the float. Not a lot of play on those tubes to allow you to pull the float mechanism out of the tank without having to take the tank off the bike. Any suggestions on how to resolve this without having to take the whole tank off again and drain it ?,.

 

[russ996duke]

number of possible problems here
could be the float arm has come adrift from the slider, so no"signal" to indicate fuel level
could be the float arm has become trapped on the tubes....if bent slightly when reassembling
what sort of pipe clips did you use??
some types are too bug for the space and once again could trap the arm
mighyt be worth a prod around gently thru filler to see what can be seen/felt, but
sorry to say think you will have to take it all apart again

oh forgot, have you checked the electrical connector is fully "connected" between tank and main harness...first place to check I think!

 

[bart2181]

no idea buddy,but i,ll be kepping my eye on this one has im hoping to fit the adventure tank(when i can find one)anyway just get your arse over here and pick these bl--dy boxes up

 

[vilguy]

Have you got it on the right threads on the tank.. i.e have you got it rotated 30 degrees round the wrong way? I did that the first time i reassembled it.. followed by prompt swearing after realising i had to strip it down again.

Electrical connector is definetly the first one to check though.

Ps. did you change the fuel filter whilst you were at it?

 

[Roger Chatterton]

To correctly align the filter/pump flange ( the big round plate that holds the filter & pump) there is a "flat" section on the flange edge -this aligns with a similar flat bit on the tank -sorry to be so un-technical here, but this is from memory ! As stated above, if the flange is out of kilter by one of the small (fragile) bolts that hold the flange on, then your level sensor may well be trapped.
Also, the filter bag that fits on the end of the fuel pump might be causing a problem too.

Maybe one of the pipes is trapping the float. Not a lot of play on those tubes to allow you to pull the float mechanism out of the tank without having to take the tank off the bike. Any suggestions on how to resolve this without having to take the whole tank off again and drain it ?,.

I can't imagine how you could resolve this without having to take off the tank ( short of groping around in tank via the filler cap , which is very easy to remove, and would make life easier !)

From one who has experienced fuel pump problems, it aint that difficult -just fit small Jubilee clips in place of the nasty BMW crimp type clips for the filter and fuel pump pipes-makes things a whole lot easier.

Good Luck- it's not rocket science, just a pain in the butt, and a bit fiddly to say the least.

 

[marcopol]

Fuel Level

Plan to fiddle around with it tomorrow, will let you know how I get on. Electrical connector was the first thing I checked. Oh and yes seeing that I was going through the pain I changed the fuel filter at the same time. Using Jubilee clips and some fuel line clamps I had machined up.

 

[Voyager]

Good Luck- it's not rocket science, just a pain in the butt, and a bit fiddly to say the least.

+1

When I got my '04 1150GSA back from the Dealers, following the 24,000 mile Service, the fuel gauge wasn't reading right. It would never get more than one bar short of full even when I brimmed the tank.

I took the float / fuel pump assembly out, checked everything over and put it back - no improvement .

I then went on a three week tour across Europe, cursing the gauge.

On returning, I had another go at it and this time I got it right, it is now back to its old self and I'm happy again.

I can only think that one of the pipes was fouling the float or maybe the tightening sequence causes the plate to lie a little off 'true' causing the float to bind.

Just put it together carefully and have another go if it doesn't work the first time.

Remember to use a new sealing ring (or dry the old one off) as they swell with fuel.

Bob.

 

[marcopol]

Fuel Level

Out of curiousity how does the float communicate with the fuel gauge if there is no electrical connection between both ?

 

[Roger Chatterton]

The fuel level sensor that floats on the fuel in the tank,( bit of wire with a polyurethane bit on the end) has a potentiometer at the other end of it ( the bit on the small pcb near the fuel pump), and, as fuel level rises/falls this sends a greater or lower voltage via the pot to the fuel gauge. The 4 pin connector that you have to disconnect to the lower right of the fuel tank carries the signal to the RIU (fuel gauge), and the power for the fuel pump. So, basically, the pot on the end of the fuel arm is really like a volume control, and as such raises or lowers the resistance of the voltage sent to the fuel gauge.
QED !!!

 

[marcopol]

Fuel Level

Sorry people for my last dumbass question. Please ignore it. Through all my confused diagnostics on this problem I incorectly envisaged the float atached to the other guts in the tank hanging off the filler. Of course its not there. Little bursts of "Homer" memory recall taking place in my head more and more these days.

 

[Roger Chatterton]

Now I'm confused:confused :

 

[marcopol]

Fuel Level

Don't worry Roger, I'm the one that was confused but I have fully recovered now.


M

 

[Roger Chatterton]

Have another try after Xmas !!

 

[Pekkavee]

Have a look in here
http://advwisdom.hogranch.com/Wisdom/R1150 GS fuel gauge.html

I had to adjust ( bend ) the sliders in the potentiometer one time to get it to work.

Pekka

 

[marcopol]

Fuel Level - Sorted

Thanks Pekkavee, moved the float arm slightly closer to the potentiometer and measure the resistance, alot better. Installed it back in the tank and hey presto. Problem now sorted after 3 attempts.

Moral of the story, if you are moving the guts in the tank for whatever reason be REEEEEAL careful not to put any strain on the float bar.

 

[Pekkavee]

Thanks Pekkavee, moved the float arm slightly closer to the potentiometer and measure the resistance, alot better. Installed it back in the tank and hey presto. Problem now sorted after 3 attempts.

Hey presto !

Thanks for thanks.

Pekka