by Thomas Walter
For those 510’s with the simple “T” style connector into the back of the alternator, this is a pretty straight forward conversion.
The Alternators
The OLD (externally regulated Alternator) had the “N” and “F” connected by the plastic “T” connector.
“N” Neutral was connected by a Y (yellow) wire.
[This is the top of the “T” connector]
“F” Field was connected by a W/B (White, black stripe) wire.
[This is the stem of the “T” connector]
The NEW IR ALT (internal regulated alternator) will have two connections, also in a T configuration like the old unit.
“S” Sense is connected to the battery (direct +12 Volts)
[This is the top of the “T” connector]
“L” Lamp is connected to the Warning lamp light.
This connection has TWO functions. By Sensing the circuit is turned on when the ignition is, it will energize the alternator. SECOND: when the alternator FAILS, and the engine is running, it will GROUND this connection – providing a ground path to turn on the “ALT” warning lamp. (you should see the “ALT” lamp glow when the ignition is first turned on, before starting the car).
How to modify the wiring
Before tossing that old voltage regulator into the trash bin
cut OFF the connector block.
Splice the W (white) wire to the Y one. (Sense circuit)
Splice the W/R (white/red) wire to the W/B one. (Lamp circuit)
This the wiring at the HARNESS, compare it to the regulator wiring, both should be the same – but some replacement units did not follow
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