Fuel Level Gauges

A fuel level gauge shows how much fuel remains, using a sender inside the tank. This section holds a 52 mm level gauge, a tube-type sender with a separate flange gasket, and a float-type unit, so gauge and sender can be matched.

Inside a sender, a float on the fuel surface sets a resistance that changes with the level. In a tube-type sender the float slides within a vertical tube; in a float-arm sender it swings on a pivot. The gauge turns that resistance into a needle position, so gauge and sender must share one resistance standard.

Fuel surges under braking and cornering, so a reading taken on track swings about. Trust the figure with the car at rest on level ground, and keep a reserve for the slosh that can uncover the pickup in long corners.

Choose the sender for the tank:

• Tube type: suits a deep tank or fuel cell with a flat top, standing vertically in a flange with its gasket. Its length must suit the tank’s inside depth.
• Float type: suits wider, shallower tanks where the float can move freely without touching baffles.
• Gauge: 52 mm in black, for a standard panel hole or pod.

Drain the tank before opening it, and purge the vapour before any cutting, as even an empty tank can hold an explosive mixture. Keep sparks and heat well away. Fit a new gasket whenever the sender comes out, tightening the screws evenly so the flange seals flat. Ground the sender if its circuit needs it, then check the empty and full readings before relying on the gauge.