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Isuzu c240 Engine

Dec 02, 2015

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ISUZU C240

  • 1INTRODUCTION

    GENERAL

    This section has the description and the repair proce-dures for the engine and the fuel system Removal, disas-sembly, cleaning, assembly, installation, specificationsand troubleshooting procedures are included.

    DANGERSome gaskets used in this engine can containasbestos or other fibers. Breathing asbestos dust is acancer or lung disease hazard. Do not create dust!Use vacuum equipment for asbestos or follow thecleaning procedure described below.

    Use a hand scraper to remove old gasketmaterial. Do not use a power tool orcompressed air.

    Make sure the gasket material is wet withwater or oil to prevent particles in the air.

    Discard all asbestos material in a closedcontainer while it is still wet. Put anASBESTOS warning label on the container.Discard asbestos material safely.

    CAUTIONDisconnect the battery cables before doing anydisassembly and repair to the engine or parts of theelectrical system.

    The diodes and resistors in the electrical system canbe damaged if the following cautions are notfollowed:

    Do not disconnect the battery when the engineis running. The voltage surge can damage thediodes and resistors.

    Do not disconnect an electric wire before theengine is stopped and the switches are OFF.

    Do not cause a short circuit by connection ofthe electric wires to the wrong terminals.Make sure a correct identification is made ofthe wire before it is connected.

    Make sure a battery is the correct voltage andpolarity before it is connected.

    Do not check for current flow by making aspark because the transistors can be damaged.

    DESCRIPTION

    The Isuzu C240 diesel engine is a fourcylinder enginethat has a displacement of 2369 cm3 (144.5 in3). The fir-ing order is 1342. The No. 1 cylinder is toward theend of the engine with the fan. The serial number of theengine is found on the righthand side of the crankcaseat the No. 1 cylinder location.

    The cylinder head has a small ignition chamber aboveeach cylinder. The diesel fuel is injected into this igni-tion chamber at the beginning of each power stroke ofthe piston. This design of the combustion chambersgives better fuel efficiency and less engine noise at theengine speeds used in a lift truck. A glow plug is also in-stalled in each ignition chamber. These glow plugs arecold start aids to make the diesel engine easier to startwhen the engine is cold.

    The valve seats and valve guides can be replaced duringan engine overhaul.

    The crankshaft has five main bearings. The main bear-ing in the center of the crankshaft is also the thrust bear-ing and has thrust washers (thrust bearings) on each sideof the main bearing.

    The pistons are aluminum alloy and have four pistonrings. Each of the three compression rings have a specialshape designed for its position on the piston. The fourthpiston ring is the oil control ring.

    The engines used in the S/H1.253.00XL(S/H2560XL) units have an auxiliary gear drive on thetiming cover for the hydraulic pump. On theH2.003.20XM (H4065XM) units the hydraulic pumpis driven by the transmission.

    Isuzu C240 diesel engines installed in lift trucks beforeApril 1990 all have a fuel injection pump, Model PE4A,made by Diesel Kiki under license from Robert Bosch.This fuel injection pump has four plunger assembliesthat supply fuel to the four fuel injectors.

    Engines with a fuel injection pump, Model PE4A, havea pneumatic governor to control the maximum enginespeed. The operation of this governor is described in theFuel System later in this section.

  • 2FIGURE 1. ISUZU C240 DIESEL ENGINE

    12621

    1. FILL CAP FOR ENGINE OIL2. FUEL FILTER3. FUEL INJECTION PUMP4. DRAIN PLUG, ENGINE OIL5. CRANKSHAFT PULLEY6. FAN7. COOLANT PUMP8. OIL FILTER9. FUEL INJECTOR (4)

    10. OIL SUMP

    1

    2

    3

    4

    7

    6

    5

    9

    8

    10

    Some Isuzu C240 diesel engines installed in lift trucksafter April 1990 have a fuel injection pump, Model VE,made by Diesel Kiki. This fuel injection pump has oneplunger assembly that supplies fuel to the four fuel in-jectors.

    Engines with a fuel injection pump, Model VE, have amechanical governor to control the maximum enginespeed. The operation of this governor is described in theFuel System later in this section.

    Engines with a fuel injection pump, Model PE4A, musthave a shutoff valve in the air intake manifold. Thisshutoff valve prevents the engine from starting andrunning in the reverse direction.

    The design of the fuel injection pump, Model VE, pre-vents the engine from starting and running in the reversedirection. The fuel will not be sent to a cylinder during acompression stroke.

    FUEL SYSTEM

    DescriptionNOTE: Special tools and training are needed to repairthe fuel injection pump. A fuel injection pump is nor-mally sent to an authorized Diesel Kiki repair station ifrepairs are necessary. Fuel injectors also require specialequipment and training for repair. Most users have aspecial repair service do this work. The repair of thefuel injection pump and the fuel injectors are not de-scribed in this section.

    A description of the fuel systems for the fuel injectionpump, Model VE and fuel injection pump, Model PE4Aare included in the following paragraphs.

    Check the timing of the fuel injection pump as describedin Checks and Adjustments. During installation of thefuel injection pump, remove the air from the fuel systemas described in CHECKS AND ADJUSTMENTS.

  • 3FIGURE 2. THE FUEL SYSTEM, FUEL INJECTION PUMP, MODEL VE

    12627

    12628

    1. FUEL INJECTOR2. PLUNGER3. FUEL TANK4. WATER SEPARATOR5. FUEL PUMP (VIEW ROTATED

    FOR CLARITY)6. REGULATOR VALVE

    7. DRIVE SHAFT FOR GEAR,FUEL INJECTION PUMP

    8. FINAL FUEL FILTER9. OVERFLOW VALVE

    10. MAGNET VALVE11. CONTROL LEVER12. FLY WEIGHT (4)13. ROLLER HOLDER

    14. CAM DISK15. TIMER16. PLUNGER SPRING17. DELIVERY VALVE18. DISTRIBUTOR HEAD19. GOVERNOR LEVER20. ADJUSTMENT SCREW,

    FULL LOAD

    16 1715

    14

    13

    7

    12

    119

    20

    1910

    18

    2

    3

    10

    1

    4

    7

    5

    8 11

    9

    6

    2

  • 4Operation, Fuel Injection Pump, Model VE (See FIGURE 2.)The parts of the fuel system include the fuel tank, injec-tion pump and governor, fuel filters, and injectors. A ba-sic diagram of the fuel system with the fuel injectionpump, Model VE is shown in FIGURE 2.

    The magnet valve is controlled by the ignition switch.When the ignition switch is turned to ON, the coil in themagnet valve is energized. The magnet valve opens topermit fuel to flow into the pressure chamber for theplunger (2). When the ignition switch is turned to OFF,the magnet valve closes and stops the flow of fuel. Themagnet valve permits the engine to be stopped quicklywhen the ignition switch is turned to OFF.

    The drive shaft (7) is turned by the gear train in the en-gine. The fuel pump (5) is a rotary vane pump that takesfuel from the fuel tank through the water separator. Thepressure of the fuel oil from the fuel pump increaseswhen the speed of the drive shaft increases. The regula-tor valve controls the pressure of the fuel oil to the speci-fications set by the manufacturer. The fuel oil flows intothe inlet for the distributor head (18) to the pressurechamber for the plunger (2). The cam disk (14) rotatesthe plunger (2) and moves the plunger in and out of theplunger barrel. The plunger (2) increases the pressure ofthe fuel oil. The rotation of the plunger aligns the pas-sages with the ports in the distributor head (18). Eachport in the distributor head has a fuel pipe connected to afuel injector. The fuel flows to the fuel injector.The overflow valve (9) in the injection pump is a bypass valve that permits some fuel oil to return the thefuel tank. The overflow valve keeps the fuel oil at a con-stant pressure in the plunger chamber so that the fuelflow to the fuel injectors is even.

    See FIGURE 3. A control sleeve (6) slides on the plung-er and partially opens a passage in the plunger to controlthe amount of fuel oil sent to the fuel injectors. This con-trol sleeve is controlled by both the control lever and themechanical governor. The control lever is connected tothe accelerator pedal for the lift truck.

    FIGURE 3. SPEED CONTROL, FUELINJECTION PUMP, MODEL VE

    12630

    1. CONTROL LEVER2. SHAFT, CONTROL LEVER3. GOVERNOR4. FLYWEIGHT (4)5. GOVERNOR SLEEVE6. CONTROL SLEEVE7. PLUNGER8. BALL JOINT9. ASSEMBLY, GOVERNOR LEVER

    10. ADJUSTMENT SCREW, FULL LOAD11. RETAINER PIN12. GOVERNOR SPRING

    1

    2

    34

    5

    6 78

    9

    10

    11

    12

  • 5Operation, Fuel Injection Pump, Model PE4A

    The parts of the fuel system include the fuel tank, injec-tion pump and pneumatic governor, fuel filter, injectorsand the air control valve. The fuel pump is fastened tothe side of the fuel injection pump and is actuated by thecam shaft in the fuel injection pump. The fuel pumptakes fuel from the fuel tank and sends it through the fuelfilter. The fuel goes from the fuel filter to the fuel reser-voir in the fuel injection pump. The fuel injection pumpsends the correct amount of high pressure fuel to eachfuel injector. The high pressure fuel opens the push rod(valve) in the fuel injector to send a spray of fuel into thecombustion chamber. A basic diagram of the fuel sys-tem is shown in FIGURE 4.

    The parts of the fuel injection pump are shown inFIGURE 5. The camshaft in the injection pump actuatesthe four plunger assemblies. Each of these plunger as-

    semblies sends fuel under high pressure to the fuel injec-tors. The fuel injection pump is turned by the camshaftgear.

    FIGURE 4. THE FUEL SYSTEM, FUEL INJECTION PUMP, MODEL PE4A

    97111. FUEL INJECTOR2. FUEL TANK

    3. FUEL