Kohler Command PRO ECV630 Service Manual page 59

b. If pressure is too low, install in-line ''T'' between
pump and regulator and retest pressure at that
point. If it is too low there also, replace fuel pump.
3. If pump did not activate (step 2), disconnect plug
from fuel pump. Connect a DC voltmeter across
terminals in plug, turn on key switch and observe if a
minimum of 7 volts is present. If voltage is between
7 and 14, turn key switch off and connect an
ohmmeter between terminals on pump to check for
continuity.
a. If there was no continuity between pump
terminals, replace fuel pump.
b. If voltage was below 7, test wiring harness and
relay as covered in Electrical Relay.
4. If voltage at plug was good, and there was continuity
across pump terminals, reconnect plug to pump,
making sure you have a good connection. Turn on
key switch and listen for pump to activate.
a. If pump starts, repeat steps 1 and 2 to verify
correct pressure.
b. If pump still does not operate, replace it.
Fuel Pressure Regulator Details
A
I
H
Pressure Regulating
A
Spring
C Diaphragm
E
Fuel Chamber
G Return Port (to tank)
I Valve
Depending on application, regulator may be located in
fuel tank along with fuel pump, or outside tank just down
line from pump. Regulator is a sealed, non-serviceable
assembly. If it is faulty, it must be separated from base/
holder assembly and replaced as follows:
1. Shut engine off, make sure engine is cool, and
disconnect negative (-) battery cable.
2. Depressurize fuel system through test valve in fuel
rail.
3. Access regulator assembly as required and clean
any dirt or foreign material away from area.
24 690 02 Rev. D
B
C
D
E
F
G
Pressure Regulating
B
Chamber
D Valve Seat
Outlet Port (to fuel
F
rail)
H Inlet Port
KohlerEngines.com
4. External Regulator-
a. Remove screws securing mounting bracket to
regulator housing. Remove O-Ring and pull
regulator out of housing.
b. Remove snap ring and remove regulator
from base/holder.
Internal (In-Tank) Regulator-
Remove screws securing retaining ring and
regulator in base/holder assembly. Grasp and pull
regulator out of base/holder.
5. Always use new O-Rings and hose clamps when
installing a regulator. A new replacement regulator
will have new O-Rings already installed. Lubricate
O-Rings (external regulator) with light grease or oil.
6. Install new regulator by carefully pushing and
rotating it slightly into base or housing.
a. External Regulators with Square Base Housing
Only; Install a new O-Ring between regulator and
mounting bracket. Set mounting bracket into
position.
b. Secure regulator in base with original retaining
ring or screws. Be careful not to dent or damage
body of regulator as operating performance can
be affected.
7. Reassemble and connect any parts removed in step
3.
8. Reconnect negative (-) battery cable.
9. Recheck regulated system pressure at fuel rail test
valve.
Fuel Rail
Fuel rail is mounted to throttle body/intake manifold. No
specific servicing is required unless operating conditions
indicate that it needs internal cleaning or replacement.
It can be detached by removing mounting screws and
injector retaining clips. Thoroughly clean area around
all joints and relieve any pressure before starting any
disassembly.
Throttle Body/Intake Manifold Assembly
Throttle body/intake manifold is serviced as an
assembly, with throttle shaft, TPS, throttle plates,
and idle speed adjusting screw installed. Throttle
shaft rotates on needle bearings (non-serviceable),
capped with rubber seals to prevent air leaks. A throttle
shaft repair kit is available to replace shaft if worn or
damaged. Appropriate TPS Initialization Procedure must
be performed after any throttle shaft service.
Idle Speed Adjustment (RPM)
Adjustment Procedure
1. Make sure there are no fault codes present in ECU
memory.
2. Start engine and allow it to fully warm up and
establish closed looped operation (approximately
5-10 min.).
EFI SYSTEM-BOSCH
59