First of all HELLO!
I've been lurking on this board for over 10 years, and I finally decided I had to join.
Sorry to take so long, but I'm not the most fastidious "post your entire life on the internet for all to see and comment" type of guy.
I purchased my '66 911 Chassis # 304093 in 2003. It was running poorly, had the wrong plugs, the suspension bushings needed refreshing and the brakes were seized. I tackled those problems and finally had a decent running car.
The main reason for posting today is because my car now has a charging problem.
When I originally purchased the car, it had a no-name internally regulated alternator installed, with no resistor at the idiot light. Once trouble started (and I was unable to adjust the belt due to the different housing & pulley) I bought the correct fan housing, fan, and *luck* found an original Bosch alternator at Hershey in 2012 for $40!
In 2013 to get ready for Hershey, I put the whole shebang back together, hooked up the orig. 47 yr. old VR and VIOILA! Running & charging fine!
Now it's back to ORIGINAL and I CAN PROPERLY ADJUST MY FANBELT! YAY!
I finally had the engine & trans restored from 2014-16, and had the original Bosch alternator reinstalled.
Drove all summer '16 with no issues when suddenly on a nice PCA FALL tour, light came on faintly, there was no charge at the battery and my car wouldn't restart when we stopped for a break. Had to push start it.
I called the shop who did the work, they picked up car and replaced my original alternator with a NEW VALEO internally regulated alternator. Black DF wire was removed, taped to harness. Car returned to me "fixed", battery was charging fine (13.5-14.2V @ 2,000 + RPM measured across battery terminals).
HOWEVER, when I got the car back, I noticed the original external VR WAS STILL PLUGGED IN! HMM....
Thinks me: "Well, that's certainly weird but they must know what they're doing! Maybe it's a new fangled alternator that allows you to keep the external VR plugged in just for looks!"
The car drove fine for the next 2 months, when suddenly NOW, the light glows faintly and THERE'S NO CHARGING AT THE BATTERY!
On 8/24/17, I took both alternators (Original Bosch & internal Valeo) to an auto electric place AND BOTH TESTED FINE!
My original Bosch external VR tested bad or failing.
But that shouldn't matter with an internally regulated alt fitted to the car, right??
Conditions: Known good Valeo installed (External VR unplugged):
Light glows faintly at all RPM, increases brightness when I step on brake pedal.
Voltage at battery at rest, car not running: 13.2V
Voltage at battery, car running: 12.5V
Voltage at battery, car running, accessories on (lights): 12.2 - 12.5V
Battery accepts a charge fine from a Schumacher charger, returns to 13.2-13.5V static.
Voltage at terminal block on rear panel: 13.2V (where heavy 10ga black & 10ga red/white alt. wire are held by screw).
No resistor fitted to alt. light wiring (ever).
Red/White B+ wire has continuity from alt. to terminal block.
Black wire from battery to terminal block measures 13.2V, continuity fine.
Ground point near rear panel was checked, connectors cleaned and new washer and nut installed. Looks fine.
Questions:
1. What effect (if any) does leaving the external VR connected have on the system, when internal VR Valeo is fitted? Does this end up changing resistance at the light?
2. Since I have a charging problem, regardless of which alt. set up I use, doesn't this point to a wiring problem?
3. What else should I check? Is my wiring problem a bad connector at the ignition switch? At Starter?
4. If neither alternator is not turning on, what is the next step?
This has me totally confused. Appreciate any help. Thanks so much ALL!
Mitch