fuel pressure SSANGYONG MUSSO 2003 Owner's Manual

M162 ENGINE CONTROLS 1F1-47
3. Disconnect the vacuum hose.
4. Disconnect the circlip and remove the fuel pressureregulator.
5. Apply the oil to O-ring lightly and then replace it.
6. Installation should follow the removal procedure in the reverse order.
7. Check for fuel pressure and internal leaks by operating the engine.
2. Discharge the pressure in fuel supply system by pressing
the service valve.
Removal & Installation Procedure
1. Remove the fuel pressure test connector.

1F1-48 M162 ENGINE CONTROLSA . Valves Closed
B. Valves Opened
The pressure difference between the fuel pressure and the intake manifold is about 3.8 bars during the full load. <Operating at Idle and partial load> The spring chamber(9) is connected to the intake manifold with the vacuum hose at the intake pipe connection(7). Thenegative pressure generated in the intake manifold activates the diaphragm, and thus the fuel pressure gets reduced to the rate of the operating extent of the diaphragm by the intakemanifold's negative pressure.
Consequently, the fuel pressure in the fuel distributor changes by the intake manifold's negative pressure, and the injector'sfuel pressure gets reduced independently to the throttle valve'sposition. Thus, the fuel injection volume can only be determined according to the injector's injecting duration. 2. Fuel return line
3. Valve
5. Diaphragm
6. Compression Spring
8. Fuel Chamber
9. Spring Chamber
1. Fuel Pressure Regulator
2. Intake Manifold
3. Fuel Return(to fuel tank)
4. Fuel Supply(form fuel pump)
5. Fuel Pressure(approx. 3.8 bars)
6. Intake Manifold Negative Pressure(0 bar)
Function of the Fuel Pressure Regulator The fuel pressure regulator maintains the fuel pressure in the fuel line with the pressure of 3.2 bars to 3.8 bars according tothe intake manifold pressure. This operating pressure cannotbe changed, and the fuel injection volume will be only determined by the injection time. Over supplied fuel returns to the fuel tank through the return line. <Operating at full load>There is no negative pressure applied to the spring chamber(9) during the full load, and it is separated from the fuel chamber(8)by the diaphragm(5). When the fuel pressure goes up, the diaphragm forces the compression spring(6) in the direction of compression . At thismoment, the valve(3) sticks to the diaphragm by the fuelpressure, and the fuel return line(2) opens. The fuel over supplied returns to the fuel tank through the return line.

M162 ENGINE CONTROLS 1F1-49
The pressure difference between the fuel pressure and the intake manifold is approx. 3.2 bars during idling. <Fuel Pressure Diagram>1. Fuel Pressure Regulator
2. Intake Manifold
3. Fuel Return(to fuel tank)
4. Fuel Supply(from fuel pump)
7. Fuel Pressure(approx. 3.2 bars)
8. Intake Manifold Negative Pressure(0.6 bars)
A . Fuel pressure
B. Intake Manifold Negative Pressure
LL. Idling
TL. Partial load
V L . Full load

M162 ENGINE CONTROLS 1F1-51
Removal & Installation Procedure
1. Discharge the fuel pressure from the fuel pressure testconnector.
2. Disconnect the battery ground cable.
3. Disconnect the vacuum hose from the fuel pressure regulator.
4. Remove the cable guide.
5. Remove the fuel return and supply line.
Notice
For removal, cover around parts with cloths not to be
stained by fuel.
In case of checking the injector only, do not remove the
fuel return and supply line.
Installation Notice
6. Remove the six injector connectors.
7. Remove the two left and two right bolts and one center bolt of the fuel distributor assembly from the intake manifold. Installation Notice
Tightening Torque 25 - 30 Nm
Tightening Torque 22.5 - 27.5 Nm

1F1-52 M162 ENGINE CONTROLS8. Remove the injectors and the fuel distributor carefully.
9. Installation should follow the removal procedure in the reverse order.
10. Check for fuel pressure and internal leakage by operating the engine.
Fuel Pressure Test
1. Turn the ignition switch to "OFF" position.
2. Remove the fuel pressure test connector.
Vacuum Hose Connected (bar) 3.2 - 3.6 Vacuum Hose Disconnected (bar) 3.7 - 4.2
5. Replace the pressure regulator diaphragm if out of the specification.
3. Connect the fuel pressure gauge to the fuel pressure test
connector.
4. Test the fuel pressure at idling by operating the engine.

M162 ENGINE CONTROLS 1F1-53
3. If there is no change in fuel pressure and maintain thefollowing pressure over 30 minutes, it is normal.
Internal Leakage Test
1. Connect the fuel pressure gauge to the fuel pressure test
connector.
2. Stop the engine for approx. 30 minutes and then check the fuel pressure changes.
Fuel pressure
drops slowly 
Fuel leakage at the injector
 Faulty fuel pressureregulator'sdiaphragm and O- ring.
Fuel pressure
drops rapidly 
Faulty check valve in the fuel pump.
Possible Cause
Pressure Change
Fuel Pressure(bar) 2.5
Discharging the pressure in fuel system
1. Remove the fuel pressure test connector. Installation Notice
2. Remove the fuel pressure in fuel system by pressing the service valve with a clean, pointy tool. Notice Place a cloth so that the fuel doesn't stain around.
Tightening Torque 22.5 - 27.5 Nm

M162 ENGINE CONTROLS 1F1-57
FUEL FILTER
1 Fuel Filter
2 Outlet
Removal & Installation Procedure
1. Open the fuel tank cap and remove the fuel tank pressure.
2. Remove the fuel at (2) and in (3). Installation Notice Notice Place the fuel pump pad. There may be a corrosion due to the contact between the fuel filter and the bracket.
4. Check for leaks by operating the engine.
Notice Installation should follow the removal procedure in the
reverse order.
3. Remove the mounting bracket bolt (4) and remove the fuel
filter (1). Installation Notice 3 Inlet
Tightening Torque
25 - 30 Nm
Tightening Torque 4 - 8 Nm

1F1-58 M162 ENGINE CONTROLS
FUEL PUMP
Requirements for Fuel Pump
ItemSpecified ValueItemSpecified Value
System Pressure3.8 bar
Minimum Delivery at 8V 30 Litre/Hr
Maximum Pressure 8.5 bar (12 V)
Minimum Amount of Fuel Supply 114 Liter/Hr (12 V, 3.8 bar, -
30 ~ +70 °C)
Minimum Pressure 5.0 bar (12 V) Maximum Allowable Current
7.5 A
Nominal Voltage12 VAmbient Temperature -30 ~ +70°C
1 Reservoir Tank
2 Fuel Sensor (float/arm)
3 Resistance
4 Wiring Connector
5 Fuel Supply Pipe
7 Float
10 Flange and Harness Assembly 11 Fuel Pump
12 Spring
13 Thermister Housing
14 Thermister
15 Resistor Card and Wiper
16 Float Arm
Operating Voltage 8 V
Maximum Amount of Fuel Supply 165 Liter/Hr (12V, 3.8 bar,
-30 ~ +70 °C)

1F1-64 M162 ENGINE CONTROLS
VACUUM SYSTEM1 Purge Control Valve
2 Molded Hose
3 Insulator
4 Fuel Tube
5 Molded Hose
6 Idle Regulator
7 Resonance Flap
8 Intake Manifold
9 Fuel Pressure Regulator
10 Vacuum Line Rubber Hose11 Vacuum Tube(Gray, 270mm)
12 Molded Hose
13 Rubber Cap
18 Rubber Hose
19 Vacuum Tube(Brown or Black, 770mm)
20 Rubber Hose A To Canicter

SECTION 1F3
OM600 ENGINE CONTROLS
Specifications . . . . . . . . . . . . . . . . . . . . . . . 1F3-1Fastener Tightening Specifications . . . . . . . . 1F3-1
Maintenance and Repair . . . . . . . . . . . . . . 1F3-2
On-Vehicle Service . . . . . . . . . . . . . . . . . . . . 1F3-2
Fuel System . . . . . . . . . . . . . . . . . . . . . . . . . 1F3-2
Fuel Injection Pump Coding . . . . . . . . . . . . . 1F3-3
Fuel Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . 1F3-4
Vacuum Control System Test . . . . . . . . . . . . 1F3-5
Vacuum Pump(Sectional View) . . . . . . . . . . 1F3-10
Vacuum Pump Test . . . . . . . . . . . . . . . . . . . 1F3-11
Vacuum Pump . . . . . . . . . . . . . . . . . . . . . . 1F3-13
Vacuum Unit Replacement . . . . . . . . . . . . . 1F3-15Idle Speed Adjustment . . . . . . . . . . . . . . . .
1F3-16
Fuel Pump Test . . . . . . . . . . . . . . . . . . . . . . 1F3-18
Fuel Pump . . . . . . . . . . . . . . . . . . . . . . . . . 1F3-21
Injection Nozzle Test . . . . . . . . . . . . . . . . . . 1F3-22
Injection Nozzles . . . . . . . . . . . . . . . . . . . . . 1F3-25
Injection Nozzle Repair . . . . . . . . . . . . . . . . 1F3-27
Removal and Installation of Injection Timing Device . . . . . . . . . . . . . . 1F3-30
Injection Timing Device . . . . . . . . . . . . . . . . 1F3-35
Start of Delivery Test (Position Sensor, RIV Method) . . . . . . . . . 1F3-37
Fuel Injection Pump . . . . . . . . . . . . . . . . . . 1F3-46
TABLE OF CONTENTS
Caution: Disconnect the negative battery cable before removing or installing any electrical unit or when a tool or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will help prevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwisenoted.
SPECIFICATIONS
FASTENER TIGHTENING SPECIFICATIONS
Application
Fuel Tank Mounting Nut Fuel Pump Pressure Line Fuel Injection NozzleFuel Injection Pipe
Nozzle Tensioning NutScrew Plug Left-Hand Thread Bolt
N· m
28 - 47 13
35 - 40 18 8030 46