Voltage Regulator Problem??

Here's an example of a "loop" that could cause this to happen. Whether you have a mechanical or electronic regulator, the field circuit can/ may/ probably does have a time constant

Let's say you DO have a voltage drop in the path from the battery to the VR IGN terminal. THAT POINT right there at the VR power terminal changes with load if there is resistance/ bad connections in the circuit.

SO AS THE VR changes the field current by ramping it up and down in order to maintain charging voltage, that change in field current ITSELF comes / is sourced from THAT VERY SAME POINT. That means that change in circuit loading drags down the voltage (when field current is increased) or allows voltage to climb up (when VR drops field down). It CHANGES because there is resistance between the VR and the battery in the circuit

So AS THAT CHANGES, the actual battery voltage is constantly going up and down. The VR is attempting to make it's point in the harness at which the IGN terminal is branched off maintain at 14V, but the RESISTANCE in the harness and voltage drop caused by system current means that the battery voltage is NOT AT that same 14V.

The damn thing can get into a sort of self oscillation in that way, where it's constantly going up and down.


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ANOTHER way you could check this is to open up the harness enough to "get to" wherever the VR power / ign splice is, near the old ballast connections, and JUMPER a nice big, say no12 over to the starter relay stud or battery with good heavy clip leads. If the pulsing stops / gets less, and if battery voltage "settles down" closer to 14, you know you are on the right track