Topic: Fuel level gauge not working

[sammon287]

I have a '76 CB750A with an intermittently functioning fuel gauge. I have seen it work before, but it has been awhile. I have pulled the sender out of the tank and it looks to be in good order and tested ok with an ohm meter. Can the gauge itself be disassembled? Would it be safe to apply 12v to the appropriate wires to see if the gauge moves?

[750duo]

NO!  Do not connect 12v across the gauge!!!

The circuit works by varying the current passing through the sender - 12V (14V at cruise) is never applied to the gauge. Applying 12V will probably burn it up if it isn't already.

If you want to test it use the ohmmeter (Rx1) - Place one lead on one terminal and just tap the other lead on the other terminal while watching the needle. If it wiggles then it's probably good. If the needle goes backward, reverse the leads.

An intermittent is usually a broken or loose wire.


Good Luck     Tom