Fuel Pump - Toro Workman HDX Auto Service Manual

Fuel Pump

The fuel pump used on Workman HDX Auto vehicles is
a positive displacement electric pump that provides
pressurized fuel to the engine fuel rail in a return-less
system. The fuel pump assembly includes the fuel
pump, the fuel sender for the dash mounted fuel gauge
and the fuel filter. The fuel pump assembly is mounted
in the fuel tank. The fuel pump assembly includes a regu-
lator to maintain fuel pressure of approximately 40 PSI
(276 kPa).
Electrical power for the fuel pump is available when the
fuel pump relay is energized by the engine ECU and
when the transaxle lockout switches are properly posi-
tioned (e.g. transaxle is in 2nd gear, low range with lock-
out key switch in slow position).
NOTE: When the ignition switch is turned to RUN, the
engine ECU energizes the engine relay for approximate-
ly three (3) seconds which allows the fuel system to be
pressurized. If the engine does not start for some rea-
son, the ECU switches off the relay preventing the con-
tinued delivery of fuel. Once the engine is running, the
relay and fuel pump remain energized.
Fuel Pump Testing
1. Park vehicle on a level surface, raise bed and engage
parking brake. Stop the engine and remove key from
ignition switch. Allow engine to cool.
2. Install bed support on bed lift cylinder to prevent bed
from lowering.
CAUTION
The fuel supply hose will contain pressurized
fuel. Be careful when disconnecting fuel supply
hose. Wipe up any spilled fuel before starting the
engine.
3. Disconnect fuel supply hose from fuel rail inlet on en-
gine (Fig. 34).
4. Install a fuel pressure gauge capable of measuring
50 PSI (350 kPa) to the disconnected hose.
NOTE: If pressure gauge is connected to a tee fitting,
fuel rail and injectors can be checked for potential leak-
age while measuring fuel pump pressure.
Workman HDX Auto
5. While monitoring fuel pressure gauge, turn ignition
switch to RUN so that engine relay and fuel pump are en-
ergized. Fuel pressure displayed on the gauge should
rise. After pump relay is de−energized (approximately 3
seconds), turn ignition switch to OFF and then back to
RUN to re−energize the engine relay and fuel pump. Fu-
el pump pressure should be approximately 40 PSI (276
kPa).
6. If fuel pump pressure is low, make sure that electrical
power is available to pump and then consider a clogged
fuel filter or faulty fuel pump (see Fuel Pump in the Ser-
vice and Repairs section of Chapter 3 − Kohler Gasoline
Engine).
7. After testing is completed, make sure that key is re-
moved from ignition switch. Remove pressure gauge
from fuel supply hose. Connect fuel supply hose to fuel
rail inlet on engine and secure with hose clamp.
8. Remove bed support from cargo bed lift cylinder and
lower bed.
2
1. Fuel tank
2. Fuel pump assembly
3
1. Fuel supply hose
2. Hose clamp
Page 6 − 25
3
1
FRONT
Figure 33
3. Fuel supply hose
2
1
FRONT
Figure 34
3. Fuel rail inlet
Electrical System