CB400 NC31 Iffy fuel gauge

[tasum]

Hi there

When I got the cb400 the fuel gauge wasn't working. Once I put some fuel in it sprang into life. Been out a few times and there's still plenty of fuel, but the gauge has stopped workng again.

Can anyone suggest a solution? I was looking at some earlier posts concerning idle speed which mentions breather pipes that may be blocked. Could this be the cause? If so, can anyone help with a fix?

Does it operate on a float system, is it just a question of mt having a better look in the tank to see if there's an obstruction?

I am a novice, so I apologise of this is a daft question. I've done a search, but no fix comes up.

Thanks in advance for looking and for any help.

[tasum]

Just a quick update. The gauge started working again and then stopped.

I'm guessing there's a float or something that's getting stuck. Can anyone help?

Cheers

[Superjack44]

Check electrical connections first for any signs of corrosian especially earths

[tasum]

Check electrical connections first for any signs of corrosian especially earths

Thanks Superjack44, I will do. Cheers.

[RICKNC31]

Hi tasum i would not bother to much about the fuel gauge not working just make shure you reset your trip meter in the speedo to zero when you fill up you will then find the bike is about ready to switch to reserve about 120 miles depending how hard you are riding you the have about 25 miles on reserve to find a garage to fill up and reset the trip again job done.You can then check the electrical connections on the gauge and possibly get it working again if you want to use the gauge. There are two holes just under the filler cap in the dish around the filler hole one is for fuel spilage and one is a breather i clear mine by passing a lenghth of flexable plastic or wire of the right dimensions down the two holes it will go down about 50cm. Hope this helps rick

[tasum]

Hi tasum i would not bother to much about the fuel gauge not working just make shure you reset your trip meter in the speedo to zero when you fill up you will then find the bike is about ready to switch to reserve about 120 miles depending how hard you are riding you the have about 25 miles on reserve to find a garage to fill up and reset the trip again job done.You can then check the electrical connections on the gauge and possibly get it working again if you want to use the gauge. There are two holes just under the filler cap in the dish around the filler hole one is for fuel spilage and one is a breather i clear mine by passing a lenghth of flexable plastic or wire of the right dimensions down the two holes it will go down about 50cm. Hope this helps rick

Cheers Rick, will do both the trip trick and the wire insertion. Thanks mate

[Galen57]

Inside the tank is a simple float. It might have gotten corroded and stick somewhat if the bike sat for a while without fuel. But chances are that it is simply your connections. Clean them properly with contact cleaner and a wire brush. If that fails, you can replace the float from Honda or just use the trip meter as earlier suggested.

[tasum]

Update

discovered that putting fuel in makes the gauge work, doh

I've not looked at the pipes as I'm guessing that being a tight yorkshireman (by location rather than birth), that I just wasn't putting enough fuel in the old girl.

So all sorted and gauge working fine.

Thanks for all your help. I may take a look at the pipes to educate myself when I get the chance, so all that advice was worthwhile.

Thank you.