Sealed fuel filter on the Movano B: must the complete housing be replaced?

With the factory arrangement, yes, and this is the source of unnecessarily high servicing costs. Like the Renault Master III, the Movano B was fitted with a sealed fuel filter in which the cartridge and housing form one assembly. The customer therefore had to pay for the complete unit at every filter change even though only the filter element wears out.

How can the cost of fuel-filter replacement be reduced?

The solution is a one-off replacement of the housing with a serviceable version designed for replaceable cartridges. This housing fits the Master III, Movano B and Trafic III. Once installed, every subsequent service requires only a replacement element costing a fraction of the complete assembly. The fuel filter on these engines should be changed every 20,000 km, and more often in harsh conditions, such as refuelling at unfamiliar stations, driving on construction sites or leaving the vehicle standing for long periods with a partly empty tank. Always fit new housing O-rings during replacement. They are the most common source of air entering the system and starting problems after a service. Once the filter is closed, prime and bleed the system with the bulb until firm resistance is felt.