First off, my truck has been sitting for about a year and a half, finally have time and money to start working on it again, thankfully. Around the same time i stopped driving it, my battery wasn't charging after running the car. Took it autozone, they told me it was my VR, only getting high 12's to low 13's out of it. After pulling the regulator, it looks to be in good condition. How can I adjust the points to get the correct voltage out of it?

 

I would perform a 3G alternator upgrade. I thought 1971 used a 68tf-10316-a that is riveted shut and nonadjustable

 

2 X hd97fxdc

 

Looks won't tell you anything with a VR. See my thread on a new, in the box defective unit. Not sure what they did to test your vr.

1st thing check your battery, take it in and have it charged and tested.
2nd check your alternator
3rd check your VR.

You cannot adjust the new VR's. If they're not to spec you replace them.

 

It is an older mechanical style VR, with two modules inside, both have points on top, one has a blue plastic piece that allows the point to make contact up and down. Any thoughts? I know they are cheap to replace, but looking for knowledge for the future. Thanks for the help!

 

Marked with ID engineering number: C8TF-10316-A = Ford part number: C3SZ-10316-B .. Alternator Voltage Regulator-has points, black cover screwed on.

1974: FoMoCo replaced C3SZ-10316-B with D4TZ-10316-A .. Alternator Voltage Regulator-has points, its blue cover could be screwed or riveted on.

Applications: 1963/64 Thunderbird / 1965/81 all FoMoCo vehicles.

1982: FoMoCo replaced D4TZ-10316-A with a solid state regulator: E2PZ-10316-A (replaced in 1990 by FOPZ-10316-A [sigh]) that has a flat aluminum cover marked MOTORCRAFT on the diagonal.

When some old car people complained (no such thing as Motorcraft prior to 1973), I told them to remove the flat cover, replace with 1963/81 cover...then no one could tell the difference.

btw: Look at a 1963/81 cover...see any dents? When the points stuck (so what else is new?!), to unstick them, people rapped on the cover with their knuckles, screw driver handles.

 

I have heard of people bending the points but for the price of a new one I have never messed with them, nor did I want to take a chance on melting the wiring harness. Maybe one of the more senior members will chime in and know how to do it safely. Thanks for the correction was thinking c=6 and put it in a 6.

 

Does anyone have a wiring diagram for a 72 Ford F100 390 external VR?

 

 

One-wire solution is unarguably the best fix. But don't immediately jump on the regulator. It could be bad diodes in the alternator. Here is the Toothless Jake way to find out.

Put a tickler wire on the field connection of the alternator. Have wifey hold the voltmeter on the charging circuit. Run it up to 1000k in fast idle and stab the battery + to the field. If it not jump to 15v or so, you have bad diodes in the alternator.

There is nothing inherently wrong with the original divorced alternator/regulator design with the replacement of the old points unit with a transistorized unit. But you must keep connections polished and grounds clean.
After all, the GM one-wire system has the same bearings and diodes as the old stuff. Maybe worse, Shanghai crap. The new alternator will wear out just as fast mechanically as the old stuff.

Semper Fi