Alternator Regulators - DELCO-REMY Double Contact Regulators: Testing

After temperature is known, voltage settings can be made in relation to temperature. Also remove Heater-A/C fuse to shut off blower.

1. Connect voltmeter across battery terminals, with a 1/4 ohm-25 watt fixed resistor in positive lead. Start engine and run for 15 minutes at 1200-1500 RPM. Leave cover in place to establish operating temperature. All accessories and lights must be turned off.
2. After a 15 minute warm up cycle, cycle voltage regulator by disconnecting and reconnecting regulator connector. Raise engine speed on 2200 RPM. Regulator should be operating on upper contacts. Voltage reading should be within specifications on voltage chart.

   Ambient Temperature	Voltage Setting
   65	13.9 to 15.0
   85	13.8 to 14.8
   105	13.7 to 14.6
   125	13.5 to 14.4
   145	13.4 to 14.2
   165	13.2 to 14.0
   185	13.1 to 13.9
   205	13.0 to 13.8

   Fig 1: Double Contact Regulator Circuit Diagram (Typical With Indicator Light)

   Courtesy of GENERAL MOTORS COMPANY
   Fig 2: Delco-Remy Double Contact Voltage Regulator

   Courtesy of GENERAL MOTORS COMPANY
3. If voltage does not fall within specifications, remove regulator cover and voltage can be adjusted by turning the adjusting screw.
   NOTE: Always make final adjustment by turning screw clockwise. This insures that screw head is firmly against spring holder.

   Cycle regualtor and recheck voltage.

4. Turn on lights and accessories to operate voltage regulator on lower set of contact points. Run engine at 2200 RPM and note voltage reading. Voltage should be within.1-.4 volts lower than reading for upper set of points. If necessary to adjust, remove cover and turn nylon nut, counterclockwise to increase the difference and clockwise to decrease.
   NOTE: Best method for determining which contacts are operating is to use earphones to detect transfer.

Fig 3: Double Contact Regulator Circuit Diagram (With Ammeter)

Courtesy of GENERAL MOTORS COMPANY