FLANGE-PUMP DRIVE 7G7046 - Caterpillar

Commercial and Truck Engines: AllMachine Engines: AllEarthmoving Compactor: 826G (S/N: 7LN1-UP) 836 (S/N: 7FR1-UP)Wheel Loader: 980G (S/N: 2KR1-UP) 988F Series II (S/N: 2ZR1-UP) 990 Series II (S/N: 4FR1-UP)Wheel Tractor: 834B (S/N: 7BR1-UP)Introduction
This Special Instruction applies to all Caterpillar machines with engines that are equipped with the PRELUB® Engine Prelubrication System. The Caterpillar PRELUB System uses the starter motor to run an oil pump. This oil pump primes the engine oil system before starting the engine. This information applies to machines using the Caterpillar PRELUB system that is equipped with the 139-1585 140-3108 Timer Assemblies . There are other prelubrication systems that are installed on machines that are made by Caterpillar. This Special Instruction is not applicable to these other systems. Important Safety Information
Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs.A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools in order to perform these functions properly.Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard.Therefore, the warnings in this publication and the warnings that are on the product are not all inclusive. If a tool, a procedure, a work method, or operating technique that is not specifically recommended by Caterpillar is used, ensure that it is safe for you and for other people to use.Ensure that the product will not be damaged or the product will be made unsafe by the operation, lubrication, maintenance, or the repair procedures that are used.Normal Operation
Turn the key switch to the CRANK position and hold the key switch in the CRANK position.
The starter motor runs in PRELUB Mode. The motor spins but the flywheel is not engaged. The starter motor runs for 3 to 45 seconds until oil pressure reaches between 27 kPa (4 psi) and 48 kPa (7 psi). The oil pressure is measured at the oil pressure switch.
The key switch is still held in the CRANK position. The starter is delayed for 3 seconds and the spinning stops.
The starter then engages the flywheel and the engine is cranked normally. Basic Operation Of The PRELUB Timer
Illustration 1 g00557737
Basic PRELUB electrical schematic
Illustration 2 g00557729
Circuitry of the timer (1) Relay control. (2) Three-second delay control.Power from the keyswitch is supplied to Contact 1 of the timer when the keyswitch is in the CRANK and RUN positions. Contact 1 supplies power to the electronic circuits that are inside the timer. Contact 2 connects through the wiring harness to the starter solenoids ground terminal. When the PRELUB oil pressure switch detects pressure less than 27 kPa (4 psi), Contact 4 is connected to ground. Power from Contact 3 (CRANK) then passes through the normally