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Fri Aug 08, 2025 3:54 pm

I checked the at rest battery condition this AM and it was right a 12.6 still.

So, later in the day, I had literally five minutes to test the generator according to the speedyjim procedure. The generator does indeed produce 35+ volts when tested. It would have gone to the moon if I let it rev more. As advised, I did a short test so as not to overheat the genny...

I also went back to the battery and read voltage across the poles while running. That was quite curious. Start up showed no voltage drop oddly enough, the at idle reading was climbing to 13.40 and higher but never got as high as 14V, and then it dropped off, even with the RPMs up, leveled out at less than 13.4, more like 12.7-8 and stayed there.

What is that telling me...?

Does the speedyjim.net site offer testing for the regulator...? I will go check.

Are the stock, mechanical regulators adjustable or serviceable...? I seem to recall that this type of regulator has points...? Is that correct...?

I will find some time to go through the Tech Manual as well...

Thanks again,
Rob

Fri Aug 08, 2025 4:20 pm

radbug69 wrote: What is that telling me...?
If it was me, I'd buy/install a new Bosch solid state voltage regulator.

radbug69 wrote: Does the speedyjim.net site offer testing for the regulator...?
Speedy Jim says if the generator tests OK by his tests, then the voltage regulator is bad.

Fri Aug 08, 2025 5:30 pm

Cusser wrote: radbug69 wrote: What is that telling me...?

If it was me, I'd buy/install a new Bosch solid state voltage regulator.

radbug69 wrote: Does the speedyjim.net site offer testing for the regulator...?

Speedy Jim says if the generator tests OK by his tests, then the voltage regulator is bad.

Perfect. I'll get one heading this way. Is he Solid State Regulator a direct swap, wire for wire...?

That actually answer the question.

Thanks much.
Rob

Fri Aug 08, 2025 7:35 pm

radbug69 wrote: Is he Solid State Regulator a direct swap, wire for wire...?

YES.

This on my 1970; notice how I used steel wool to remove some paint under an attaching screw, for better grounding.

Mon Aug 18, 2025 9:31 am

Cool, easy-peasy change, new voltage regulator in.

At start up the voltage across the battery terminals read 12.66, higher rpms indicate 14.40-ish and very little dip when lights are pulled on. So, the old regulator was indeed faulty.

Thanks much, I appreciate you folks.

Going for a blast..
Rob

Mon Aug 18, 2025 12:17 pm

radbug69 wrote: new voltage regulator in.

At start up the voltage across the battery terminals read 12.66,
This is normal. Generators don't actually put out much of a charge at idle rpms.

radbug69 wrote: ... higher rpms indicate 14.40-ish
Nice! 14.4v is a solid charge voltage.

radbug69 wrote: ... and very little dip when lights are pulled on.
Good sign. It indicates that as the system draws more current (to power the headlights) the VR senses this and increases the geneator output (by varying the DF) and the VR maintains the voltage levels.
The earlier type VR did this mechanically with points. The newer style VR manages this with solid state circuity.

Wed Aug 20, 2025 3:08 pm

ashman40 wrote: radbug69 wrote: new voltage regulator in.

At start up the voltage across the battery terminals read 12.66,
This is normal. Generators don't actually put out much of a charge at idle rpms.

radbug69 wrote: ... higher rpms indicate 14.40-ish
Nice! 14.4v is a solid charge voltage.

radbug69 wrote: ... and very little dip when lights are pulled on.
Good sign. It indicates that as the system draws more current (to power the headlights) the VR senses this and increases the geneator output (by varying the DF) and the VR maintains the voltage levels.
The earlier type VR did this mechanically with points. The newer style VR manages this with solid state circuity.

Yes, I was very excited to see the voltage across all ranges. Such a satisfying repair.

I think I will add a Battery Tender loop onto the battery so that I can both, check the voltage without pulling the seat up and giving a trickle charge/float when the car is not in use for some time. We have a brutal Winter here... in my opinion.

Thanks,
Rob

Wed Aug 20, 2025 4:00 pm

Cusser wrote: radbug69 wrote: Is he Solid State Regulator a direct swap, wire for wire...?

YES.

This on my 1970; notice how I used steel wool to remove some paint under an attaching screw, for better grounding.

And keep in mind the cover of the new solid state type is HOT (as in positive 12V), so do not let it short to ground! Many add an insulator over it, but since it gets hot (as in temperature) make it non-flammable and allow air to breath around it.

Wed Aug 20, 2025 5:21 pm

Quote: add a Battery Tender loop onto the battery
installed this plate that has a 'master' cut-off switch for dash power. An analog clock in the dash uses more power than the tender puts out. A power point with 10G wire directly to the battery with tender that I added a male power point end. The power point can handle blenders, air compressors, and other 12v things. Just cut the power off with the switch, plug in the tender and it's hibernation time till spring. On the Ghia, just connect the tender to the alt. B+ and clip the alt. case. It doesn't have a current drain from a clock.

Wed Aug 20, 2025 6:11 pm

radbug69 wrote: I think I will add a Battery Tender loop onto the battery so that I can both, check the voltage without pulling the seat up and giving a trickle charge/float when the car is not in use for some time. We have a brutal Winter here... in my opinion.

I don't have special battery tender wires on my two VWs, but on my 1971 I do have an under-dash cigarette lighter socket that is wired to "always hot" terminal on the fuse box. So on that I could use a battery tender if I chose to, but of course that's not wired up for a jump start !