Flame Sensor Fuel-Powered Preheater

Flame sensor fuel-powered preheater

Note! The illustrations in this service information are used for different model years and/or models. Some variation may occur. However, the essential information in the illustrations is always correct.

Preparatory work

Removing the combustion preheater module (CPM)
Remove the control module. See: Fuel Fired Booster Heater Control Unit, B5254T7, L.H.D Fuel Fired Booster Heater Control Unit.

Removal

Removing the flame sensor




Remove the 4 screws for the cover over the fan housing. Remove the cover.

Note! The nearest connection pipe may need to be adjusted in order to remove the cover. See: Coolant pipe fuel-powered preheater, B5254T7, L.H.D Coolant Pipe Fuel-Powered Preheater.




Carefully pull the fan housing straight out, viewed from the shorter side of the engine coolant heater. See the illustration.




Disconnect the cable terminal and cable for the flame sensor at positions 1 and 2 (blue and brown).




Remove the flame sensor (1).

Installation

Installing the flame sensor
Install the flame sensor. Tighten. See Tightening torque [1][2]Body and Frame.
Install the cable terminals and cables in the connectors.
- Flame sensor in positions 1 and 2 (blue and brown).

Note! Route the cables behind the fan motor to the connector.

Carefully push the fan housing into place.

Ensure:
- that the connector is not trapped
- that the cable seal on the water pump is correctly positioned and that the cable runs behind the fan motor like the others.
Install the cover using 4 screws.
If necessary adjust the pipe coupling. See: Coolant pipe fuel-powered preheater, B5254T7, L.H.D Coolant Pipe Fuel-Powered Preheater.
Install the control module. See: Fuel Fired Booster Heater Control Unit, B5254T7, L.H.D Fuel Fired Booster Heater Control Unit.

Finishing

Testing the engine coolant heater
Carry out a performance test of the engine coolant heater. See: Fuel-powered preheater, checking Fuel-Powered Preheater, Checking.