Description and Operation of the Hydrocarbon Fuel Doser Block
The Hydrocarbon (HC) fuel doser block assembly and related parts are located on the left side of the engine. The
HC fuel doser block assembly meters diesel fuel to the HC fuel doser injector valve to facilitate regeneration of the
Diesel Particulate Filter (DPF). The fuel cutoff valve enables the flow to the electronic diesel dosing valve which
effectively meters the desired amount of diesel fuel needed for regeneration to the HC fuel doser injector valve.
Removal of the Hydrocarbon Fuel Doser Block
NOTICE
Removal/installation of the Hydrocarbon (HC) fuel doser block assembly will require that
the system be purged to remove all air in the fuel lines. Refer to DiagnosticLink® to
perform this routine service.
Note : Always disconnect the fuel lines prior to disconnecting the electrical connectors to avoid fuel contamination
into the sensors and connectors.
1. Shut off engine and apply the parking brake, chock the wheels, and perform any other applicable safety
steps.
2. Disconnect the batteries. Refer to OEM procedures.
3. Place a drip pan under the engine to collect any fuel.
4. Disconnect the air compressor inlet hose from the HC fuel doser block bracket (if required).
5. Disconnect the inlet and outlet fuel lines (1, 2) from the HC fuel doser block assembly.
6. Unplug the electrical connectors from Fuel Cutoff Valve (FCV) (1), Fuel Compensation Pressure (FCP)
sensor (2), Electronic Dosing Valve (EDV) (3) and Fuel Doser Line Pressure Sensor (4).
7. Loosen three bolts (3) and remove the HC fuel doser block assembly (2) from the HC fuel doser block
bracket (1).
Installation of the Hydrocarbon Fuel Doser Block
Install as follows:
NOTICE
Removal/installation of the Hydrocarbon (HC) fuel doser block assembly will require that
the system be purged to remove all air in the fuel lines. Refer to DiagnosticLink® to
perform this routine service.
1. Install the HC fuel doser block assembly (2) using three bolts (3); torque bolts to 32 to 36 N·m (24 to 27
lb·ft).
2. Plug in the electrical connectors to the Fuel Cutoff Valve (FCV) (1), Fuel Doser Line Pressure Sensor (4),
Fuel Compensation Pressure (FCP) sensor (2), and the Electronic Dosing Valve (EDV) (3).
3. Connect the inlet and outlet fuel lines to the HC fuel doser block assembly. Torque the banjo bolt to 15 N·m
(11 lb·ft).
4. Connect the air compressor inlet hose from the doser bracket (if equipped).
5. Tighten all connections securely.
6. Connect the batteries. Refer to OEM procedures.
7. Start the engine.
Note : It may take more than one purge attempt to completely purge all of the air from the fuel line. Do not exceed
three purge attempts.
8. Use the HC fuel doser command to run the purge function in DiagnosticLink to purge all the air from the
doser valve and line.
9. Check for any leaks.
10. Use DiagnosticLink to initiate a parked regeneration.