Should I upgrade my alternator?

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I'll have to catch it when it starts happening, pull over and put the meter on it. I'll post back once I do.

The volt meter on the dash stays near 14v but there is a slight, nearly imperceptible tick of the needle that seems to correspond with the pulsing dash lights.
 
The voltage wavers between 14.1 and 14.4v. I don't think it is rising and falling in pattern with the dash lights but it's hard to tell since it's a digital meter.

It's quite strange. It won't happen until after I've been driving for at least a few minutes. If I turn on the blower motor or the headlights it will stop, but it might start up again with very faint flashing.

Sometimes the lights will be quite bright and other times barely visible. Sometimes they blink fast and sometimes slow.

If I'm on the highway and the lights are not blinking, they will often start when I come to a stop and idle. They will sometimes blink even when the engine is under load.
 
I talked to the alternator wizards who build this custom setup and they really couldn't explain it either, other than to say that perhaps the cheapo voltage regulator they used just doesn't hack it. I've ordered a couple genuine Ford motorcraft regulators so we'll see if that helps.

If it doesn't I'm just going to ignore this as my voltage is stable and the system seems to be charging well enough.
 
This thread is getting a little old but I thought you'd enjoy some closure.

The guys who ruined the diodes, ground the rotor and disassembled & busted my vacuum pump for no good reason: Capital City Alternators in Sacramento.

I ended up having to file a dispute with my credit card company to get my money back. They had charged about $200 for their "service".

I then took all my parts over to Lehr Auto Electric just north of Sacramento, and for $60, they build mey a franken-alternator that uses the Ford voltage regulator. This has been running reliably for the last year.

As for the mystery pulsing warning lights? That's caused by the battery charge controller for my solar panels. It is a PWM controller, meaning it's pulse width modulated. When the batteries are fully charged and there isn't much draw on the electrical system, the PWM controller's pulses seem to exceed the set point on the voltage regulator, causing the lights to flash.
 
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