Usage:
This system includes a single section pump, and V-bottom pan. A prelube oil pump system on standard D399 and G399 engines is driven by a 115/230 V AC motor. Air and 32V DC driven prelube systems are available as attachments. The main lubrication system will be discussed first, then the prelube oil pump systems.
Main Lubrication System
Under normal operating conditions oil flow is as follows: lubricant from the oil pan base (17) is pumped through oil cooler (7), filter housings (8) and to oil distribution manifold (6).
A pressure regulating valve (14) mounted on the oil pan base controls the maximum pressure of oil from pump (16).
Oil filter bypass valves in each filter housing, bypass oil to the oil manifold when the flow is momentarily restricted because of cold oil. When the oil is warm, only filtered oil is furnished to the engine bearings. If the oil filter elements become restricted, the bypass valves open and the oil flows directly to the oil distribution manifold.
The oil distribution manifold directs oil through connecting passages to the engine internal and external components, timing gears and front accessory drive.
External Component Lubrication
The turbocharger, governor, governor booster pump (4), fuel injection pump housing and the governor and fuel pump drive shaft receive lubricant from the fuel pump and governor drive housing oil manifold (3). When equipped with an oil pressure shutoff it is also supplied with lubricating oil from this manifold. Drain back oil from these components returns to the oil pan base.
In this D399 Engine schematic, pressure oil flow is shown in dark grey and suction oil, drain back oil or splash lubricated points are shown in light grey. 1-Turbocharger oil return line. 2-Turbocharger oil supply line. 3-Fuel pump and governor drive housing oil manifold. 4-Governor booster oil pump. 5-Valve rocker mechanism. 6-Oil distribution manifold. 7-Oil cooler. 8-Two filter housings. 9-Camshaft bearings. 10-Crankshaft main bearings. 11-Crankshaft connecting rod bearings. 12-Oil spray orifices. 13-Prelube system pump. 14-Pressure regulating valve. 15-Suction bell. 16-Single section oil pump. 17-Oil pan base.
Internal Components
The oil distribution manifold (6) directs filtered lubricant through passages and tubes to: piston oil spray orifices (12), valve rocker mechanism (5), camshaft bearings (9), crankshaft bearings (10), connecting rod bearings (11), fuel pump and governor drive housing oil manifold (3).
Timing Gears
Oil under pressure flows to the camshaft thrust bearing. The gears receive lubrication from drain back oil from the turbocharger, camshaft and crankshaft rear bearings.
Front Accessory Drive
The oil distribution manifold (1), delivers oil through a drilled passage to the front main bearing, and from this passage to the front accessory drive. Steel tubes in the front accessory drive housing supply oil to the bearings which support the idler gears (7) and (8), water pump gear (2), oil pump gear (3), main idler gear (4) and on D379 Engine the balancer gear (5).
In this schematic pressure oil flow to the accessory drive gear bearings is shown in grey. 1-Oil distribution manifold. 2-Water pump gear. 3-Oil pump gear. 4-Main idler gear. 5-Balancer gear. 6-Crankshaft gear. 7-Idler gear. 8-Idler gear.
Oil Pressure
When the engine is running at 1200 RPM with SAE 30 oil, temperature at 200 ± 10°, oil pressure measured at oil pressure gauge hole in V of block should be as indicated in the chart.
7S8875 HYDRAULIC TEST BOX
A lower pressure reading, 15 PSI (1,0 kg/cm2), is normal at low idling speeds. An 8M2744 Gauge, which is part of 7S8875 Hydraulic Test Box, can be used for system pressure checking.
Turbocharger Lubrication Valve - (D379, D398, G379 and G398 Engines)
When the oil pressure gauge and speed limiter operation indicates adequate oil pressure and bearing failure or wear occurs in both turbochargers, check the turbocharger lubrication valve operation. The valve can be stuck and allow unfiltered oil to constantly lubricate the turbocharger.
EARLIER ENGINE TURBOCHARGER LUBRICATION VALVE LOCATION
LATER ENGINE VALVE AT RIGHT REAR OF ENGINE
Prelube System - (D399 and G399 Engines Only)
The prelube system consists of a pump (1) driven by a 115/230 V DC motor (3) switches, valve and adapting lines and fittings. The motor and pump are mounted on the right side of the engine. This system has a separate suction tube in the oil pan base and it discharges oil in the engine oil supply at the tee (2) below the oil cooler.
Major component location of the prelube oil pump system. Components identified are: 1-Oil pump. 2-Tee. 3-Electric motor. 4-Check valve.
The prelube pump will start when the diesel engine starting switch is moved to the ON position. When oil pressure of 1-2.5 PSI (0,07-0,18 kg/cm2) is developed in the supply lines to the turbochargers, the switch closes. This energizes the starter solenoid and cranking of the engine begins.
When the diesel engine starts and the starting switch is released to stop cranking, the prelube motor stops and engine lubrication is supplied by the engine oil pump. A check valve (4) prevents engine oil pump pressure from circulating oil through the prelube pump during normal engine operation.
Prelube Oil Pump Removal and Installation
Lower the crankcase oil level in oil pan base to a level below the base connection of the prelube pump supply tube.
Disconnect the battery ground terminal.
Remove 110 volt current supply to the pump motor.
Disconnect and tag the wires to identify at assembly.
Loosen or remove the suction and pressure lines. When all oil lines and switch brackets have been removed or disconnected, support the pump assembly and then remove four bolts to remove the prelube pump and motor.
ELECTRICAL DIAGRAM 32 V STARTING 50 A ALTERNATOR AND 32 V PRELUBE
Pump weighs approximately 150 lbs. (68 kg).
Install in the reverse order of removal. Be sure the check valve is installed to block flow of oil from the engine main oil pump.
Prelube Pump Disassembly and Assembly (Later)
When removing the head (3) from the housing (2), use care to avoid damage to any gaskets that may be between the head and housing. Gaskets of .001 in. (0,025 mm), .003 in. (0,076 mm) and .005 in. (0,127 mm) are available for rotor end play adjustment.
To install seals (1) use a 1P482 Driver and 1P529 Handle to install them, one at a time, from the head end of the housing. Sealing lips should face away from each other. The hollow head screw (6) should be installed on the outlet side of the rotor (4).
PRELUBE PUMP
1-Seals. 2-Housing. 3-Head. 4-Rotor. 5-Gear.
Fill the area between the lips of the seals with grease. Coat the rotor hub with light oil and install the rotor (4) hub through the seals. Use care to avoid folding under the inner seal lip.
INSTALLING SEALS
Place the idler gear (5) on the idler pin and proper number of gaskets on the housing flange. Tighten the head in place. The rotor end clearance should be .003-.005 in. (0,076-0,127 mm). Measurement of this clearance can be made with a thickness gauge through the port opening. Add or remove gaskets to adjust the clearance.
Install the full length key in the motor shaft keyway. Key must be full length to avoid misalignment of the pump rotor which could cause serious damage to the pump. Slide the pump on the motor shaft and fasten securely with the four capscrews.
6-Hollow head screw.
Prelube System Testing (Later Type)
Pressure Testing
The components of this system that can be checked are lines, oil pump and check valve. There are two test plugs in the pump housing. Test pressure with the 8M2744 gauge which is part of 7H8875 Hydraulic Test Box. Pressure should be 25 PSI (1,75 kg/cm2) on a gauge sensing the pressure at plug (1) in outlet side of the pump. Low oil pressure and flow may be increased, if the pump is worn, by removing gaskets from between head (2) and housing. End play of the rotor should be .003-.005 in. (0,076-0,127 mm). The same test plug location as above can be used to check the functioning of check valve (3). After the engine is running and oil pressure is shown on the instrument panel, and the prelube pump motor has stopped, no pressure at the pump indicates the check valve is working.
PRELUBE PUMP TEST LOCATION
1-Test plug. 2-Pump head. 3-Check valve.
Electrical Testing
The electrical components in this circuit are the pump motor, relay, oil pressure switch and starter switch. Momentary jumper contact around the oil pressure switch to test the components should be done with CAUTION.
Relay-Find the faulty component by first determining there is AC supply to the pump motor. Attach a jumper wire from the positive (+) side of the battery to the relay terminal (1) to complete the circuit through the relay coil. The relay should complete the AC circuit and cause pump motor to run. With the pump developing pressure in the lubrication system, indicated by pressure at the gauge, lubrication is assured during additional checks. REMOVE THE JUMPER WIRE.
CHECKING PRELUBE SYSTEM RELAY
1-Relay terminal.
Oil Pressure Switch - With a jumper wire between both terminals (1) of the oil pressure switch, momentarily engage the starter switch. If the starter and solenoids engage, then the oil pressure switch is at fault and should be replaced. Leave the jumper in place if the switch is not at fault and check the start switch.
PRELUBE SYSTEM OIL PRESSURE SWITCH
1-Terminals.
Starter Switch - Use a jumper wire between the starter battery terminal (2) and starter relay terminal (1). If the starter and solenoids engage, the fault is in the starter switch. If the starter switch is not faulty, remove all jumper wires. See the topic STARTING SYSTEM for further checks of the starting system circuit components.
CHECKING STARTER SWITCH
1-Starter relay terminal. 2-Starter battery terminal.