Next problem: alternator adaptation

CS-130 alternatorThe alternator used on the 1992 DOHC is a Delco CS-130, seen here at the left.

CS-130D alternator The 1995 uses the newer design Delphi CS-130D, as shown here on the right. The engine’s mounting bracket is different because the 130D’s housing is smaller, despite using the same size 130mm stator. The 130D has larger bearings and internal fan blades rather than the external ones of the 130. It produces the same 105 peak amps but it runs cooler, and puts out 15.5V rather than the 13.5V of the CS-130. The CS-130 was an alternator of legendary reliability, and the CS-130D manages to improve on that. Unfortunately, its wiring is different enough that the D does not work with the 1992 wiring harness.

The problem, as it turns out, is that the voltage supplied on the “L” wire (explained below) isn’t sufficient to activate it. It needs at least 3 volts, and I got barely 0.5. This may have been because I have a voltage gage rather than an idiot light. So to adapt it, I had to make use of an undocumented and unused port on the CS-130D connector. It’s easy to do, though this simplicity belies what I had to do to figure it out. You’ll just need to make slight modifications to the CS-130D’s connector. Take a look at this diagram.

CS-130D plug

Carefully disassemble the connector by prying the plastic tabs at the back away from the body and expose the internals. You’ll see that this is a very highly engineered connector. Remove the rubber plug for the S port, and get yourself a connector pin from an electronics store. Take the connector to the store with you if you don’t know what it’s supposed to look like. Crimp it on an 18ga wire about 6 inches long with a large eyelet on the other end, and insert it into the S port. Connect the other end to the alternator’s BAT terminal. This is your L circuit bypass.

Next to it, the F/I port should be connected to the 12V ignition circuit. You’ll have two brown wires on the old CS-130 connector. Find which one gives you 12V switched when the car is on using a voltmeter. Connect that wire to the F/I port of the 130D connector. The other wire is used only if you do not have a voltage gage in your car and only a warning light. In this case, do not connect the F/I wire and connect that wire to the L port instead.

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