Glow Plug Fuel-Powered Preheater

Glow plug 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 glow plug/pressure equalizer




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.





Remove:
- the cable terminal and cable for the flame sensor in positions 1 and 2 (blue and brown)
- the cable terminal and cable for the glow plug in positions 9 and 12 (white and brown).




Disconnect the flame sensor (1) and with it the holder for the pressure equalizer (2).

Remove:
- the glow plug
- the pressure equalizer and the fuel pipe.

Note! Make sure that the O-ring and the filter are also removed. Otherwise the fan motor has to be disconnected from the combustion housing.

Installation

Note! For tightening torques, see Tightening torque [1][2]Body and Frame

Installing the glow plug / pressure equalizer

Install:
- the pressure equalizer
- the flame sensor together with the holder. Tighten
- the glow plug. Tighten.
Install the cable terminals and cables in the connectors.
- Flame sensor in positions 1 and 2 (blue and brown).
- Glow plug in positions 9 and 12 (white 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 connection, 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
Perform a performance test of the engine's preheater. See: Fuel-powered preheater, checking Fuel-Powered Preheater, Checking