NEW INTEGRATED CIRCUIT REGULTORS-SOME GENERATORS

A new type of regulator is being phased in as a running change in production and service on some models of the above generators. The 10SI/100 generator, used primarily in automotive and light truck applications, is not involved in this changeover. (Figure 1) .

The old regulator part numbers, and the new replacement part numbers are listed below.

OLD PART NO. NEW PART NO. ------------ ------------ 1116404 1116405 1984287 1116405 1116389 1116406 1974623 1116406 1894489 1116407

The new regulators feature a small web between the two male blade terminals. The web electrically connects these two terminals together. The regulator is to be used with nothing else connected to these two terminals.

The regulators being replaced are of two types:

A. Regulators with a resistor soldered to the two main terminals

B. Regulators which used a voltage adjustment cube attached to the two terminals.

The resistor and voltage adjustment cube are no longer used, since the web electrically connects the two terminals together. One exception is 32 volt 30SI model 1117733, which will continue to use the old type regulator and the voltage adjustment cube in production and service.

On some 10SI and 27SI models, a new "rubber plug", or vinyl cover, part number 1987869, may be assembled onto the end frame over the regulator terminal to retard entry of water, dirt, and other foreign material. If this coveris not available, the voltage adjustment cube may be reassembled to the generator in the normal manner to act as a plug. The voltage adjustment cube will have no effect electrically, since the two terminals are "shorted together" by the web. A plug is not needed on 20SI, 29SI, 30SI and 40 SI models.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.