GUARD GP-CAB 1761353 - Caterpillar

Charging System
5P300 Electrical Tester. Make reference to Special Instruction (GEG02276) and to the instructions inside of the cover of the tester, when testing with the 5P300 Electrical Tester.The condition of charge in the battery at each regular inspection will show if the charging system is operating correctly. An adjustment is necessary when the battery is always in a low condition of charge or a large amount of water is needed (one ounce per cell per week or every 50 service hours).Test the charging units and voltage regulators on the engine, when possible, using wiring and components that are a permanent part of the system. Off the engine (bench) testing will give an operational test of the charging unit and voltage regulator. This testing will give an indication of needed repair. Final testing will give proof that the units are repaired to their original operating condition.Before starting on the engine testing, the charging system and battery must be checked. See the following Steps.1. Battery must be at least 75% (1.240 Sp. Gr.) full charged and held tightly in place. The battery holder must not put too much stress on the battery.2. Cables between the battery, starter and engine ground must be the correct size. Wires and cables must be free of corrosion and have cable support clamps to prevent stress on battery connections (terminals).3. Wires, junctions, switches and panel instruments that have direct relation to the charging circuit must give proper circuit control.4. Inspect the drive components for the charging unit to be sure they are free of grease and oil and are able to drive the load of the charging unit.Alternator Regulator (Prestolite)
The regulator components are sealed in an insulation of epoxy. The regulator is an electronic component with no moving parts (solid state) and has an adjustment screw (1) on the back. This voltage adjustment screw is used to meet different operating needs at different times of the year. An increase or decrease by .5 volts from the normal (N) setting is made by removing the regulator and changing the position of the adjustment screw and washer. An increase to the voltage will be made by moving the screw and washer to the "H" position (2).
ALTERNATOR REGULATOR
1. Adjustment screw with washer. 2. High output position. 3. Orange wire to battery. 4. Green wire to field terminal of the alternator (F). 5. Low output position.Alternator Regulator (Delco-Remy)
Earlier
When the alternator is charging the battery too much or not enough, an adjustment can be made to the alternator regulator. Remove the plug from the cover of the alternator regulator and turn the inside adjustment with a screwdriver. Turn the adjustment one or two notches to change the alternator charging rate.Later
The later alternator has a different location for the voltage adjustment screw than the early alternator. The voltage adjustment screw for the later alternator is located under the end plate.To adjust the voltage setting, use the following procedure:1. Remove end plate (2) and cover (3) from the alternator.2. Remove the rubber