why does my fuel gauge always read full

[FB400]

I had the bike apart for a repaint and the fuel pump was removed, wrapped and stored over the winter

Now since putting the bike back together no matter how little gas is in the tank the gauge always reads full.

I checked the connectors and I removed the pump to see if the arm was stuck.
I checked the parts diagram for the proper position of the pump. The outlet points to the back just slightly toward the right side

I am a little bit baffled on this one.
Will someone offer me some help?

Thanks!

 

[TownsendsFJR1300]

When the wire to the pump "gauge switch" (in the tank) are disconnected, it'll flash low. Obviously this isn't your problem.

Its sounds like perhaps the float arm got bent on the install and may be stuck in the up position. I don't think you can see the arms movement in the tank (mines full right now and I can't see it anyway). If you CAN SEE IT, is it moving downward (or stuck towards the top)?

If that doesn't pan out, a PIA, but if you can run the tank close to empty and pull the pump. Hook up just the gauge connector to the harness (no need to plug in the pump) and turn on the key. Rotate the arm up and down (with the key on) watching your fuel gauge.

Obviously, it should go up and down with the movement. If it still shows full, you likely have a bad float switch.

BTW, with the pump out of the tank, it should be much easier to see inside the tank IF ANYTHING (the arm) is rubbing up against the side or middle hump hanging up..

 

[FB400]

SOLVED!!

Scott - thank you for the post. it got me thinking about a solution rather than just thinking this was bad news.

A little over 3 years ago I effed up my pump when I dropped the tank. The fuel inlet broke off and I ended up having to buy a new pump I guess because the used FZ6R pump I bought did not work and I was being really impatient trying to find the right pump for the Fz6 heading into the height of riding season.

When I assembled the bike a week ago I had looked at the Yamaha parts fiche for the Fuel tank and the pump is oriented wrong hence my confusion as to why this gauge stopped working.
The Yamaha fiche shows the outlet of the pump pointing toward the back and about 45 degrees to the right.
Then I found a photo of the bottom of tank and fuel pump before I took it off when I broke it back in May 2012. This photo represents how Yamaha assembled it at the factory. Sure enough the orientation is pointing to the back but about 45 degrees to the left instead. I tested the pump fuel gauge and installed it the same way as in the 2nd photo and now the gauge works as it should.

 

[TownsendsFJR1300]

Excellent Tom!!! Glad it was something simple!! :thumbup:

Its been a couple of years since I had the pump out but I thought yamaha had something so it would only go in one way(obviously not).

Stuff like that, especially MORE complicated dis-assembly, I'll draw a pic of say the direction of the pump in relation to the tank. As in your case, probably some masking tape on the tank itself, then draw the exact location below the tape for exact re-assembly.

I had to change out the pressure switch on my air compressor (contacts burned up over 6 years). The hard parts only go on one way, but there's wires for 110, wires to the motor, that attach to that switch. I definitly drew that out, crossed wires plugged into 110 will be bad works great, no air leaks (surprisingly)