KOMATSU HD1500-7 TRUCK

MAJOR COMPONENTS

Engine TransmisinFinal Drive Operators CabPower SteeringBrake SystemRetarderSuspensin

MAYOR COMPONENT LOCATION

SPECIFICATIONS

EngineKomatsu . . . . . . . . . . . . . . . . . . . . . . . SDA12V160*Number of Cylinders . . . . . . . . . . . . . . . . . . . . . . . 12Operating Cycle (diesel) . . . . . . . . . . . . . . . 4-StrokeRated . 1109 kW (1487 SAE Brake HP) @ 1900 rpmFlywheel . . . 1048 kW (1406 SAE HP) @ 1900 rpmWeight (dry) . . . . . . . . . . . . . . . .5813 kg (12,815 lbs)

TRANSMISINAutomatic Electronic Shift Control with AutomaticClutch Modulation In All Gears.Torque Converter. . . . . . . . 3-Element, Single-stage, . . . . . . . . . . . . . . . . . . . . . . . . Two-phaseLockup Clutch . . . . . . . . . . . . . . . Wet, Double-disc, . . . . . . . . . . . . . . Activated in F1-F7 gears.

Transmission . . . . . . . 7 Forward Speeds, 1 Reverse, Planetary Gear, Multiple Disc Clutch, Hydraulically Actuated, Force-lubricatedGear . . . . . . . . . . . . . . . . . . . . . kph . . . . . . . . mph1 . . . . . . . . . . . . . . . . . . . . . . . . 11.0 . . . . . . . . . 6.82 . . . . . . . . . . . . . . . . . . . . . . . . 14.6 . . . . . . . . . 9.13 . . . . . . . . . . . . . . . . . . . . . . . . 19.5 . . . . . . . . 12.14 . . . . . . . . . . . . . . . . . . . . . . . 24.5 . . . . . . . . 15.25 . . . . . . . . . . . . . . . . . . . . . . . . 32.6 . . . . . . . . 20.36 . . . . . . . . . . . . . . . . . . . . . . . . 44.2 . . . . . . . . 27.57 . . . . . . . . . . . . . . . . . . . . . . . . 58.0 . . . . . . . . 36.0Reverse . . . . . . . . . . . . . . . . . . 10.6 . . . . . . . . . 6.6

Hydraulic SystemHydraulic Pumps . . . . . . . . . . . . . . . . . . . . . . . . . (3)Hoist (Tandem Gear). . . . 805 l/min. (213 gpm) @ 18 960 kPa (2,750 psi)

STEERING (PISTON)... . . 221 l/min. (58.5 gpm) @ 18 960 kPa (2,750 psi)Brake (Tandem Gear) . . . . . .1512 l/min. (400 gpm)Hoist Control Valve. . . . . . . . . . . . . . . .. Spool TypePositions. . . . . . . . . . Raise, Hold, Float, and Lower.

HYDRAULIC CYLINDERSHoist . . . . . . . . . . ..... . . 3-Stage Telescoping PistonSteering . . . . . . . . . . . Twin - Double Acting PistonRelief Valve Setting . . . . . . .18 960 kPa (2,750 psi)Filtration . . . . . . . . .. In-line Replaceable ElementsSuction . . . . . . . . . ... . .Single, Full Flow, 100 MeshHoist & Steering . . . . . . . . Dual, Full Flow, In-line. . . . . . . . . . . .. High Pressure. Beta 12 Rating = 200Transmission . . . . . .. . . . . . . . .Dual, High Pressure

SERVICE BRAKESActuation: . . . . . . . . . . . . . . . . . . . . . . . All-HydraulicFront . . . . . . . . . . . . . . . . . Oil-Cooled, Multiple-DiscRear . . . . . . . . . . . . . . . . . . Oil-Cooled, Multiple-Disc. . . . . . . . . . Both act as service and retarder brakesRetarder Brakes:Normally Applied . . . . . . . . . Manually By Operator.. . . . . . . . . . . . . . . . . . . . . . . . . . . . (w/ ARSC control)Automatically Actuated . . . . . . . . . . . . . . . . . . . . . . .when engine speed exceeds the rated revolutionsof the shift position for the transmission.Parking Brake: . . . . . . Spring-Applied, Oil Released. . . . Dry Caliper Disc Actuates On Rear Drive ShaftEmergency Brakes: Manual or automatic operation.

COOLING SYSTEMDESCRIPTION

The cooling system dissipates heat generated in the engine, transmission and brake systems. Radiator (1, Figure 3-1) is filled with a water/ethylene-glycol coolant mixture. The coolant circulates through the engine, transmission cooler (4), and brake cooler (5)

TRANSMISSION AND BRAKE COOLERS

The brake cooler reduces the oil temperature in the wet disc brake (and hoist) oil circuit. This occurs during service brake application and primarily during retarder operation. The transmission cooler reduces the temperature of the transmission oil supply.

AIR FILTRATION SYSTEMAIR CLEANERIntake air, required by the engine, enters through the air cleaners. The air cleaners discharge heavy particles of dust and dirt using centrifugal action. Finer particles are removed by passing air through filter cartridges.FILTER SERVICE INDICATOR

BATTERIES AND STARTING SYSTEMBATTERIESA 24VDC electrical system, generated by four 12 volt batteries, supplies power for the starting system. The batteries are wired in series and parallel. The four batteries are a lead-acid type, each containing 6, 2-volt cells.

ENGINE PRELUB SYSTEM

The engine is equipped with an pre-lubrication system designed to reduce wear that occurs during dry starts.The Prelub system automatically fills engine oil filters and oil passages prior to cranking at each engine startup. The system also prevents startup if oil pressure in the engine is insufficient.Prelub PumpOil Pressure SwtichOil pressure switch (1 Figure 2-4) is a 17 kPa (2.5 psi), normally closed (NC) switch.

Check Valve

The check valve prevents backflow from the engine back to the prelub pump after the engine is started. Failure to prevent backflow to the pump will result in pump failure.

Timer Solenoid

Timer solenoid (1, Figure 2-2) controls the prelubrication cycle by completing the power supply circuit to operate the prelub pump.

ELECTRICAL SYSTEM COMPONENTSRELAY CENTERThe relay center shown in Figure 3-3 contain a maximum of 33 relays in its three convenience centers. Circuit breakers are not used on this board.

FUSE PANELThe fuse panel is located in the rear electrical compartment behind the drivers seat (Figure 3-7). The panel consists of three fuse blocks..

BATTERY EQUALIZERThe majority of circuits on the truck operate on 24 VDC. However, several components require 12 VDC for operation.

BODY POSITION SWITCHESTwo magnetically activated proximity switches sense the position of the truck dump body.

SPEED SENSORS

FAILURE CODES

ACTION CODE DISPLAYSIf there is a machine failure or if maintenance is necessary, an action code is displayed on the character display to recommend a suitable response.

FAILURE CODE TABLETROUBLESHOOTING

TORQUE CONVERTER AND TRANSMISSIONTRANSMISSIONTorqflow transmission (9, Figure 2-1) has seven forward speeds and one reverse speed. The transmission contains planetary gears and hydraulically actuated multiple-disc clutches. The transmission is pressure lubricated for optimum heat dissipation.Drive line adapter (2) containing rubber dampers, couples the engine to the transmission and torque converter. The adapter reduces harmful engine shock and vibration to the transmission. A lock-up system, consisting of a wet, triple-disc clutch, can be actuated in all forward gears for higher fuel savings.

TORQUE CONVERTER AND TRANSMISSION

TORQUE CONVERTERThe torque converter is a three element, singlestage, two phase torque converter with lock-upclutch.MAIN RELIEF VALVEFunctionThe main relief valve maintains the main hydraulic pressure in the transmission control circuits. Thevalve also controls the oil flow to the transmissionclutches.

TORQUE CONVERTER RELIEF VALVE

Function

The torque converter relief valve protects the torque.Converter oil circuit by preventing the oil pressure from rising to an abnormally high pressure.

TORQUE CONVERTER REGULATORVALVETorque converter regulator valve (Figure 2-8) isinstalled in the output circuit of the torque converter.The valve regulates the hydraulic pressure inside thetorque converter to 517 kPa (75 psi).

LOCK-UP CLUTCHThe lock-up clutch is located in the torque converter. Refer to Figure 2-4. The clutch is used to create a direct mechanical connection from the engine to the transmission. This direct drive connection helps minimize energy loss that occurs while the engine is hydraulically connected to the transmission via the torque converter.

Lock-up Clutch Accumulator

Lock-up clutch accumulator (2, Figure 2-11) hasbeen added to the lock-up clutch circuit as a protectivedevice. The function of the accumulator is to dampen normal system pressure pulsations in the fill switch hydraulic circuit. Repeated pulsations acting on the switch can cause the switch to fail.

HYDRAULIC PUMP TRANSMISSION

LUBRICATION RELIEF VALVE

FUNCTION

Transmission lubrication relief valve (3, Figure 2-15) is installed on the left side of transmission case (1).This valve prevents abnormal pressure in the transmission lubrication circuit.

Operating PressureEngine @ 2100 rpm Oil Temperature @ 70 - 90 C (158 - 194 F). . . . . . . . . . . . . . . . . . . . 304 97 kPa (31 14 psi)Cracking Pressure: . . . . . . . . . . . . . 343 kPa (50 psi

LUBRICATION RELIEF VALVE

TRANSMISSION CONTROL VALVEELECTRONIC CONTROL MODULATION VALVE (ECMV)

ECMVs consists of two valves, a pressure controlvalve and a flow sensor valve.Pressure Control Valve.The pressure control valve contains a proportionalsolenoid. The solenoid uses the current sent from thetransmission controller and converts it into hydraulicpressure. Refer to Figure 2-19

The flow sensor valve is actuated by a trigger fromthe pressure control valve. The flow sensor valve hasthe following functions:1. The valve is opened until the clutch is filled with oil, reducing the time taken for oil to fill the clutch.2. When the clutch fills with oil, the valve closes. A full signal is sent to the controller.3. While there is hydraulic pressure applied to the clutch, a full signal is sent to the controller to indicate whether there is hydraulic pressure present.ECMV and Fill Switch Each ECMV is equipped with one fill switch. When the clutch is completely filled, the flow sensor valve sends a signal to turn the fill switch on. As a result of this signal, the oil pressure starts to build up.

The front drive shaft is located between the engine and the transmission. The rear drive shaft is located between the transmission and the rear axle. The two drive shafts differ in length and design. The front drive shaft is a fixed length. The rear driveshaft has a slip-joint to permit oscillation of the rear axle.

DRIVE SHAFTS

SUSPENSIONS

FRONT SUSPENSIONThe suspension system supports the weight of the chassis and absorbs the shock from uneven road surfaces to provide a comfortable ride for the operator. At the same time, it maintains the stability of the machine by ensuring that all four wheels are always in contact with the ground surface.The suspensions are hydro-pneumatic components containing oil and nitrogen gasThe front suspension consists of two basic components; a suspension cylinder and an A-arm.

The rear suspension cylinders consist of two basic components, a suspension housing attached to the truck frame and a suspension rod attached to the axle housing.Each rear suspension cylinder contains a charging valve (1, Figure 3-1). The suspension must be properly maintained with oil and nitrogen for optimum performance.The suspension is also equipped with a pressure sensor. The sensor senses internal gas pressure and sends that information to the VHMS controller. The information is used to calculate payload data by the payload meter.REAR SUSPENSION

BRAKE CIRCUIT COMPONENT SERVICEBRAKE VALVEThe brake valve is a pressure modulating valve, actuated mechanically (brake pedal) or hydraulically through the automatic apply valve.The brake valve controls the pressure delivered to the front brake relay valve and rear brake dual relay valve which provide the apply pressure for the front wheel and rear wheel disc brake assemblies. Apply pressure can be modulated from zero to maximum braking effort by use of the foot pedal.

BRAKE ACCUMULATORS

There are two identical hydraulic brake accumulators located on the brake manifold in the brake control cabinet behind the operator's cab. The left accumulator supplies the pressure necessary for actuation of the rear service brakes. The right accumulator suppliespressure to activate the front service brakes.

BRAKE COOLING VALVE (BCV)

BRAKE COOLING VALVE (BCV)When the brakes are not applied, the brake cooling valve (Figure 3-25) bypasses part of the brake cooling oil to reduce power loss when traveling. This is accomplished through activation of main spool valve (4) by switching solenoid valve (3) on or off.The truck is equipped with two brake cooling valves

PARKING BRAKE

Description

The disc type parking brake, mounted on the final drive input, utilizes three brake heads with spring cans (hydraulic cylinders) containing internal springs which apply the parking brake when hydraulic pressure is released.When the engine is running and the park brake switch is in the OFF position, hydraulic oil is routed to the spring cans to extend the pistons and mechanically retract the disc brake pads to release the park brake.

HYDRAULIC SYSTEM OVERVIEW

The following information describes the major components of the hydraulic system including the hoist circuit, steering circuit, and brake cooling circuit

SYSTEM COMPONENTSHYDRAULIC TANKBLEED-DOWN MANIFOLDHOIST VALVEHOIST PUMPBRAKE COOLING PUMPBRAKE CONTROL VALVE (BCV)HIGH PRESSURE FILTERSLOW PRESSURE FILTERS

STEERING CIRCUITCOMPONENT DESCRIPTION

Steering Control ValveLa operacin de la unidad de control de la direccin es tanto manual como hidrulica. Este componente incorpora una vlvula de control hidrulica; el esfuerzo de direccin aplicado al volante de la direccin por el operador acciona la vlvula, la cual a su vez, dirige el aceite hidrulico a travs de la vlvula del amplificador de flujo hacia los cilindros de la direccin para proporcionar al operador direccin asistida

BLEED-DOWN MANIFOLD

Recibe aceite de a bomba de direccin y frenos atreves de un filtro de alta presin y dirige el aceite hacia los acumuladores, circuito de frenos, amplificador de flujo.

BLEED-DOWN SOLENOID

Cada vez que el interruptor de partida se se pone en OFF con el camin detenido se energiza el solenoide de purga del acumulador de direccin. Cuando se energiza el solenoide, toda la presin de direccin hidrulica incluido los acumuladores es purgada de vuelta hacia el tanque hidrulico.

Despus de aproximadamente 90 segundos, el solenoide se des energizara para cerrar la vlvula de retorno al tanque, para entonces todo el aceite de los acumuladores se debe haber devuelto al tanque.En el encendido el circuito de direccin y frenos se cargara.AccumulatorsThe accumulators are bladder type accumulators.The top side of the accumulators are charged to 9653 kPa (1400 psi) with pure dry nitrogen. The nitrogen pressure increases directly with steering circuit pressure. When steering circuit pressure reaches 18,961 kPa (2750 psi),

A pressure switch for the steering oil is located above the bleed-down manifold. The pressure switch is normally closed and is used to activate a warning buzzer and a red warning light when the key switch is turned to the ON position. These alarms are used to alert the operator that steering circuit pressure is less than 12,755 kPa (1850 psi).

At the top of each accumulator is another pressure switch. These pressure switches are used to activate the accumulator warning light when the nitrogen pressure is below 5861 kPa (850 psi). If the warning light illuminates with the key switch ON, the nitrogen must be charged to 9653 kPa (1400 psi).

Flow Amplifier

El amplificador de flujo (4, Figura 4-1), ubicado en el riel izquierdo del chasis delante de los acumuladores, se usa en el circuito de la direccin para proporcionar un alto volumen de aceite requerido para los cilindros de la direccin.El amplificador de flujo utiliza el flujo proveniente de la unidad de control de la direccin para determinar una cantidad proporcional del flujo a ser enviado desde el mltiple de purga a los cilindros de la direccin.

STEERING/BRAKE PUMP

The pump is a pressure-compensated, piston pump. The pump delivers oil through a high pressure filter to the bleed-down manifold. At the bleed-down manifold, oil is directed to the steering circuit (accumulators,flow amplifier, etc.) and to the brake system components mounted in the hydraulic cabinet.

HOIST CIRCUIT

Hoist PumpThe hoist pump is a tandem gear type pump driven by the transmission PTO gear case. The pump has a total output of 845 l/min (224 gpm) at 2100 rpm. Maximum hoist pump output pressure is 18, 961 kPa (2750 psi). Pump output pressure is limited by relief valves located within the hoist control valve.