GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1998 🢒 GMC P42 Commercial Chassis 🢒 Engine 🢒 Engine Controls - 4.3L 🢒 Distributor Overhaul

Disassembly Procedure

    Object Number: 185201 Size: LH

    Notice: It is possible to install the distributor driven gear in two positions. Make sure when installing the gear that the dimple found below the roll pin hole in the gear is on the same side as the rotor segment. The dimple will not align directly with the rotor segment. If not, the gear is installed 180 degrees off and a no start condition may occur. Premature wear and damage may result.

  1. Remove the 2 screws that hold the cap to the housing.
  2. Remove the cap from the housing.
  3. Remove the 2 screws from the rotor.

    4. Object Number: 184499 Size: SH

    Notice: Failure to keep cleaning agents away from the distributor HALL EFFECT switch may cause premature failure.

  4. Remove the rotor. Note from which locating holes (3) the rotor was removed.
  5. Remove the 2 screws holding the hall-effect switch.
  6. Ensure that the square cut hole (2) in the vane wheel is aligned with the hall-effect switch.
  7. Remove the hall-effect switch.

    8. Object Number: 4377 Size: SH
  8. Note the dimple located below the roll pin hole on one side of the gear. Use the dimple in order to properly orient the gear on the shaft during assembly.

    9. Object Number: 4358 Size: SH
  9. Remove the roll pin from the shaft.
  10. Remove the following components from the 5.7L engine:
    11. • The driven gear
    • The washer
    • The tang washer

    Object Number: 185211 Size: MH
  11. Remove the following components from the 7.4L engine:
    12. • The driven gear
    • The washer
    • The tang washer
    • The thermal insulator

    Important: If the shaft cannot be removed from the distributor housing due to varnish buildup, use a cloth dampened with varnish remover in order to clean the shaft.

  12. Remove the shaft.

Assembly Procedure

    Object Number: 185201 Size: LH
  1. Install the hall-effect switch.

    2. Important: Do not overtighten the screws as the base may strip.

  2. Install the 2 screws holding the hall-effect switch.
  3. Install the shaft.
  4. Install the following components to the 5.7L engine:
    5. • The tang washer
    • The washer
    • The driven gear

    Object Number: 185211 Size: MH
  5. Install the following components to the 7.4L engine:
    6. • The thermal insulator
    • The tang washer
    • The washer
    • The driven gear

    Object Number: 4377 Size: SH
  6. Ensure that the dimple located below the roll pin hole is on the same side as the rotor segment.

    7. Object Number: 4358 Size: SH
  7. Install the roll pin.

    8. Object Number: 184499 Size: SH
  8. Align the rotor with the mounting holes (1) and the locating holes (3).
  9. Install the rotor.

    10. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  10. Install the 2 screws that hold the rotor.

    11. Tighten
    Tighten the distributor rotor screws to 2 N·m (20 lb in).

  11. Installation of the distributor into the engine requires the distributor cap off the assembly. Refer to Engine Controls.