Proheat X45–School Bus - Manual (Page 63)

Fuel System – Step 1
Check: Fuel and fuel supply
a) The PROHEAT operation when supplying fuel from a direct
source.
Test Procedure — Supplying fuel from a remote source:
a) Remove the fuel supply line from the outlet of the fuel
regulator.
b) Put this end of fuel into a small container of CLEAN fuel that is
about the same level as the regulator centre similarly to Figure
5-4. This will remove the vehicle fuel supply, fuel pump and
regulator from the fuel delivery.
b) Switch the PROHEAT on and operate for at least 90 seconds.
Observe the operation.
If the PROHEAT functions correctly, the fault is with the regulator,
fuel supply or fuel pump. Check fuel lines, connections and
routing back to fuel tank. Proceed to Step 2.
If a Start diagnostic code is indicated, the problem is with the
nozzle or compressor fuel system. Proceed to Step 4.
5-6 PROHEAT INSTALLATION & SERVICE
Figure 5-3 Fuel System Schematic
AIR
COMPRESSOR
FUEL TANK
FUEL PICK-UP
NOZZLE
FUEL INLET
ELECTRODE
FLAME SENSOR
FUEL REGULATOR
FUEL PUMP
FUEL SUCTION
AIR FILTER
FUEL PRESSURE
COMPRESSED AIR
FUEL SUCTION