Erratic fuel gauge

[DaveFhlug]

The fuel gauge on my Spider is fine until it drops to about the half tank mark. Once there it bounces all over the place and then falls to the empty mark. Is this a symptom of a bad sending unit or the gauge itself?

Dave

[Danq]

the sending unit is the weak link because of the movement of the float arm over the fine wires of the rheostat. If the tank has been kept at below a 1/2 tank for the last 25 years or so then the wire in this area are shot. you could put a ohm meter on the sender to check the sender. check the sender at full and again when the guage does it's dance.