When it is possible, make a test of the charging unit and voltage regulator on the engine, and use wiring and components that are a permanent part of the system. Off-engine testing or bench testing will give a test of the charging unit and voltage regulator operation. This testing will give an indication of needed repair. After repairs are made, perform a test in order to prove that the units have been repaired to the original condition of operation.
Test Tools For The Charging System
| Required Tools | ||
| Part Number | Description | Qty |
| 8T-0900 | Ammeter | 1 |
| 6V-7070 | Digital Multimeter | 1 |
8T-0900 Ammeter
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| Illustration 1 | g00296441 |
8T-0900 Ammeter | |
The 8T-0900 Ammeter is completely portable. This ammeter is a self-contained instrument that measures electrical currents without breaking the circuit and without disturbing the conductor's insulation.
The ammeter contains a digital display that is used to monitor current directly within a range between 1 ampere and 1200 amperes. If an optional 6V-6014 Cable is connected between this ammeter and a digital multimeter, current readings can be viewed directly from the display of the multimeter. This can be accomplished under only one condition:
- the readings are less than 1 ammeter.
A lever opens the ammeter's jaws over a conductor. The conductor's diameter can not be larger than 19 mm (0.75 inch).
The spring loaded jaws close around the conductor for measuring the current. A trigger switch controls the ammeter. The trigger switch can be locked into the ON position or into the OFF position.
After the trigger has been working and the trigger is turned to the OFF position, the reading appears in the digital display for five seconds. This accurately measures currents in areas with a limited access. For example, these areas include areas that are beyond the operator's sight. For DC operation, an ammeter contains a zero control, and batteries inside the handle supply the power.
Note: Refer to Special Instruction, SEHS8420 for more information about using the 8T-0900 Ammeter.
6V-7070 Digital Multimeter
 | |
| Illustration 2 | g00283566 |
6V-7070 Digital Multimeter | |
The 6V-7070 Digital Multimeter is a hand-held service tool with a digital display, that is completely portable. This multimeter is built with extra protection against damage in field applications. The multimeter is equipped with 7 functions and 29 ranges. The 6V-7070 Digital Multimeter has an instant ohms indicator. This indicator permits checking continuity for a fast inspection of the circuits. The multimeter can also be used for troubleshooting capacitors that have small values.
Note: Refer to Special Instruction, SEHS7734 for complete information for the use of the 6V-7070 Digital Multimeter .
Alternator Regulator
The charging rate of the alternator should be checked when an alternator is charging the battery too much. The charging rate of the alternator should be checked when an alternator is not charging the battery enough. Refer to the Specifications Module, SENR3582 in order to find all testing specifications for the alternators and regulators.
No adjustment can be made in order to change the rate of charge on the 12 V alternator regulators. If the rate of charge is not correct, a replacement of the regulator is necessary.
See Special Instruction, REHS0354, "Charging System Troubleshooting" for the correct procedures to use to test the charging system. This publication also contains the specifications to use when you test the charging system.
Tightening The Alternator Pulley Nut
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| Illustration 3 | g00283568 |
Tools for tightening the alternator pulley nut (1) 8T-9293 Torque wrench (2) 8S-1588 Adapter (1/2 inch female to 3/8 inch male) (3) 2P-8267 Socket assembly (4) 8H-8517 Combination wrench (1-1/8 inch) (5) 8T-5314 Socket | |
Tighten the nut that holds the pulley with the tools shown. Refer to the Specifications module for the torque.