Issue 15: Fuel tank sender unit fitment

The situation

Vehicle manufacturer’s are increasingly trying to reduce the weight of vehicles and maximise under vehicle space. As a result, fuel tanks can come in a variety of shapes and sizes. They contain ledges, corners and in some cases even have baffles (found in the fuel tank and used to slow down or divert the flow of gases, liquids and sound) and regulators.


For this reason, correct fitment and location of in-tank fuel units during replacement is imperative for accurate fuel level indication.

How to fit it correctly

If the tank units are not fitted correctly, the float arm can get caught on a ledge in the tank or trapped against an internal component, which in turn can cause an incorrect fuel level reading, resulting in the engine stalling due to the vehicle running out of fuel.


Most in-tank sender units have marked indicators on the top flange cover, which should be lined up to markings on the fuel tank itself to ensure correct location of sender units and correct operation.Alignment of these indicators should be checked after securing the lock ring to ensure no movement has occurred. The use of correct tools will assist this.

Fuel tank sender unit

When carrying out fuel tank sender unit replacements, be sure to have these markings in line to avoid customer breakdowns and possible false warranty claims.

Cambiare Tips and Tricks Issue 15 PDF