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Alternator Installation Checklist



IMPORTANT: Place vehicle in neutral and disconnect batteries before working on the electrical system. DO NOT TEST THE ALTERNATOR BY DISCONNECTING THE BATTERY LEAD TO SEE IF IT SPARKS. THIS WILL DAMAGE THE ALTERNATOR AND MAY VOID THE WARRANTY.
  1. TEST THE BATTERIES BEFORE INSTALLING THE ALTERNATOR

    Batteries must be in good condition, have the proper capacity and be fully charged. A defective battery may cause an alternator to fail prematurely and a discharged battery will shorten the life of the alternator. An alternator is designed to maintain the charge in a battery, not to recharge the battery.

  2. INSPECT ALL WIRE AND BATTERY CABLES

    Battery cables, alternator wiring, and wiring connections must be tight, in good condition, and free of corrosion. Loose connections and corrosion add resistance to the charging system and will result in damage to the alternator. If upgrading the vehicle to a higher amperage alternator, insure that the wiring in the charging circuit is of sufficient size to carry the additional output.

  3. INSPECT THE FAN AND PULLEY

    A damaged fan will affect the cooling of the alternator, decreasing its life. A damaged pulley may affect the drive belts causing them to slip and drive the alternator at improper speeds. If the fan and pulley are out of balance, vibration will cause premature alternator failure.


  4. PROPERLY TORQUE THE FAN AND PULLEY IN PLACE

    The rotor may not spin freely when the alternator is removed from the carton. Do not reject the unit! Install the fan and pulley and torque the pulley nut to 70-80 ft. lbs. This will locate the rotor properly in the alternator and it will turn freely.

  5. USE PROPER MOUNTING HARDWARE

    Use grade 5 bolts and self-locking nuts when mounting the alternator. Use hardened flat washers under the bolts and lock nuts. If using a slotted type adjusting bracket, place a hardened flat washer between the adjusting bracket and alternator adjusting ear. Do not use lock washers.

  6. IF ALTERNATOR FAILS TO CHARGE AFTER PROPER INSTALLATION

    If the alternator fails to charge after proper installation, it may be necessary to increase the engine speed or magnetize the rotor.

  7. ENERGIZING SPEED

    Sufficient alternator speed must be obtained before the regulator turns on and energizes the field circuit. This may be higher than "idle" speed. If this condition exists, increase engine speed until the regulator turns on. Once the regulator turns on it will remain on until the engine is stopped.

  8. MAGNETIZING THE ROTOR

    Magnetism is usually retained by the rotor to provide sufficient voltage build-up to turn on the field circuit when the engine is started. However, units that have been in inventory, disassembled or serviced may need to have this magnetism re-established. This is accomplished by magnetizing the rotor. To magnetize the rotor, connect the alternator to the electrical system in the normal manner. With the engine off momentarily, connect a jumper lead from the battery positive to the relay terminal of the alternator. (The relay terminal is the small pin type terminal generally covered by a rubber cap.) This applies to both positive and negative ground systems. This will restore the magnetism in the rotor and the alternator will begin operating correctly.


  9. TEST ALTERNATOR OPERATION

    Alternator output should be 20% over total system requirements. The regulator has been preset to O.E. specifications. Vehicle indicator gauges may not reveal accurate charging system operation. Reliable test equipment should be used when testing or troubleshooting the electrical system.

This document was provided by Haldex Brake Systems.

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