C2 voltage regulator adjustment

[William F.]

Archives always say " see service manual-it's straight forward."However test instruments have changed since '67 and procedure in manual including "attach resistor in circuit isn't so straightforward. What's simple method of determining if regulator is giving proper 13.5-14.5V at 1500rpm and where do you check this voltage?Jerry Fuccillo(out of pocket presently) shows a digital plug in V meter in lighter socket giving 14V in a previous post but didn't give specifics. Is this method accurate? Lights and heater or AC blower on or off for this test? I do know where the adjustment screw in the regulator is , just not how to know when adjustment is correct.
Help! and thanks!

[Jack H.]

Re: C2 voltage regulator adjustment

Voltage regulator senses the level of the battery and instructs the alternator to turn ON/OFF as required to keep the battery charged. The reason for reving the engine to 1500 RPM range is to get sufficient output from the alternator to deliver sufficient charging current to the battery.

Where should you test the voltage level? Well, if you put your meter directly across the battery, you're looking at the net effect of the charging system, eh?

[Ronald L.]

Re: C2 voltage regulator adjustment

Jack...

and the adjustment process?

[Jack H.]

Re: C2 voltage regulator adjustment

You already said you knew where the adjustment screw was, plus you knew the need to rev the engine to +1500 RPM and had read the service manual instructions...

[Ronald L.]

Re: C2 voltage regulator adjustment

Jack, William did, I did not... How do you validate clean then if they got wet?

[Jack H.]

Re: C2 voltage regulator adjustment

Dah, what are you trying to 'clean' that got wet?

The cover for the V-reg seals to the base via a rubber gasket. These regulators are virtually water proof!

If you're saying your regulator had a seal breach and you find rust/scale on the internal components, it's time to go SLOW and do NOT presume that all that's needed is a slight 'tweak' of the regulator's voltage adjust screw!

There are two relays inside: one is the field cut-in/cut-out relay and its operation is controlled by the specific air gap + the stiffness of its point mounting arm.

The second relay is the actual voltage regulator component. It has a plastic air gap knob that's factory set & forget. On the back side of this relay there's a tension spring + adjusting screw. This controls the specific target voltage level the regulator tries to maintain.

There are air gap and point gap specs for BOTH of the relay components that should be FIXED and never need re-adjustment throughout the regulator's useful life. But, like all electro-mechanical components, they DO have a useful life and when they're gone, they're gone (absent a complete overhaul/replacement of internal parts).

Few bother to try and 'save' these regulators because they were SO common (good replacements are easy to find) and today's drop-in, solid state regulators do an EXCELLENT job! It's only the 'numbers' guys (like us) who want to preserve/restore...

Now, once a given regulator has been 'water logged' and there's OBVIOUS rust/scale on its internal parts, quite a few things can/do change. That includes the stiffness of the relays' contact point mounting arms, the integrity of the point contact surfaces, various compression welded wiring interfaces and specific air gaps + spring stiffness.

Normally, I'd either walk away from a regulator that's been 'water logged' or send it out to a pro who has replacement internal components & the set-up/test tools to verify proper operation.

Understand that the service literature which describes various add-in resistors and discrete tests to perform was based on the PRESUMPTION the regulator was rather new, had reasonably good internal parts, and simply needed minor re-adjustment. Once you're dealing with a 'basket case' (or near basket case) regulator, all bets are off for 'saving' a given regulator via minor adjustment...