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If someone would volunteer to suffer through another alternator question, I would be grateful. I have teh CB performance wiring schematic, and have mine hooked up that way, ACCEPT that i had the D+ to indicator to ground, not to switched power. I think someone made a comment that this was the way to do it on one of the threads I read.
Anyway, my light never came on (maybe a bad bulb?) the way I now think it should have, being wired as it is. My alternator B+ wire goes to the starter solenoid, battery power post, just like in the CB diagram, but I'm only showing 12.5V on a meter, the VDO dash gauge, and everywhere else I check the circuit. No hot wires or fires have resulted, but with the motor off, I read 'some' level of conductivity between B+ and ground (~6.28 ohms, I think).
QUESTIONS: Should the B+ to ground read "open" when the motor is off?
Has something blown up, such that the alt. has no output under these conditions?? I read that the alternator output is governed by the regulator feedback; the higher the imbalance between alt. and batt., the higher the alt. output. SO...with the D+ circuit being open, does this mean (I hope!) that the alt. output would be 'minimal'? One guy told me that the D+ doesn't have to be attached at all (doesn't seem right).
I'll check it out tonight, but I sure hope that bulb is blown...!
Sorry for the redundancy; ridicule will be tolerated graceously!!(especially if it's laced with some help :) )
Tim
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If someone would volunteer to suffer through another alternator question, I would be grateful. I have teh CB performance wiring schematic, and have mine hooked up that way, ACCEPT that i had the D+ to indicator to ground, not to switched power. I think someone made a comment that this was the way to do it on one of the threads I read.
Anyway, my light never came on (maybe a bad bulb?) the way I now think it should have, being wired as it is. My alternator B+ wire goes to the starter solenoid, battery power post, just like in the CB diagram, but I'm only showing 12.5V on a meter, the VDO dash gauge, and everywhere else I check the circuit. No hot wires or fires have resulted, but with the motor off, I read 'some' level of conductivity between B+ and ground (~6.28 ohms, I think).
QUESTIONS: Should the B+ to ground read "open" when the motor is off?
Has something blown up, such that the alt. has no output under these conditions?? I read that the alternator output is governed by the regulator feedback; the higher the imbalance between alt. and batt., the higher the alt. output. SO...with the D+ circuit being open, does this mean (I hope!) that the alt. output would be 'minimal'? One guy told me that the D+ doesn't have to be attached at all (doesn't seem right).
I'll check it out tonight, but I sure hope that bulb is blown...!
Sorry for the redundancy; ridicule will be tolerated graceously!!(especially if it's laced with some help :) )
Tim
That would be me.....the D+ is known as the "61 wire" aka to the dash alt indicator bulb.

It gets wired like this ..the alt. D+ wire is run to the ground (negative/brass casing)) side of the indicator bulb and the positive (hot/ bottom silver tit) side of the buld gets wired to dash ground . I know this sounds "bass ackwards" but it is the way it works !
Alan
Alan,

I must disagree with you here. D+ should be wired, via a warning lamp, to ignition switched +12V. This is how I wired it in my vehicle, and it works as expected.

Ignition On, Engine Not Running:
D+ is at approximately ground, as the alternator is not generating any electricity, so the rectifiers will be at ground. Potential across bulb is 12V - bulb will LIGHT

Ignition On, Engine Running:
D+ is at approximately 14V as alternator is generating electricity, and rectifiers will be outputing 14V. Potential across bulb is 14-14 = 0V - bulb will NOT light. Any rectifier fault will cause voltage output to drop or fluctuate, causing lamp to come on/flicker.

Ignition Off, Engine Off
D+ is at approximately ground, as is the ignition switched side of bulb. - Bulb will not light.

Aha! I'm not crazy...but even more happy that I wired per the CB Perf. guide and it works as many of you have described; the light comes on as expected with the 12V switched source supplying power when the alt. is not turning, and goes off as soon as teh engine fires. The extra 'blah' on the throttle some described is true in my case too, which had me fooled for a second; the meter sstayed at 12V until I hit the gas, then it immediately jumped to 14V and the light went out - fine with me...
I was sooooo happy, I decided to take the car around the house to the front yard for some pics. On the way up, I hit something an punctured the oil cooler. I actually put the first 2 miles on the car though. God has a sense of humor!! :) Any good suggestions for oil cooler locations?
Alan - I'm not sure how your's is working the way described; seems like the light would be on all the time with an alt. source (12V) and ground??
Simon - maybe if you filled in the 'how it's wired' blank, we could see the differences.
Nevertheless, thanks for the help
-Tim
Tim,

Not sure I understand your question.

B+ will always read 12V as its directly connected to the battery via a thick cable (Don't forget to fit a 60A fuse inline here as a fire prevention strategy in case you ever get a short....) even when the ignition is off. Of course, the difference when the engine is running is the current flowing to charge the battery.

Hey Simon.....here we are again!

Tim: Simon is absolutely right (nice description, BTW!) and the detailed wiring is thus:

B+ (the BIG terminal on the alternator) goes to the starter battery terminal via a BIG wire and a 60amp in-line fuse (that's optional, but Simon found out the hard way why you should have one).

(Simon: All the powder gone?)

D+ from the Alternator goes to one side of an isolated dash lamp (neither side goes to ground) via a small (16 - 18 gauge) wire. The other side of that dash lamp goes to +12V, the same source as your ignition, so it's "off" when the key is off.

That's it.
Gordon,

Thanks for reminding me!! Infact I just received a replacement extinquisher for my garage today.

Remnants of powder hung around and made a nuisance of itself down on the case below the alternator stand after the first round of cleaning - and was causing lots of corrosion. Alternator strap, dissy, alt stand, even the rocker cover tops!

I ended up removing all of the ancilaries again a couple of weekends ago to get rid of it once and for all. Took a whole day but this time it seems to be gone for good.

Simon
Thanks again, guys. The question to Simon was what was the physical wire hookup (schematic) that was followed?? Gordon filled that in nicely. I'll take the 60A inline fuse unde advisement. My wire is about 10G. on the alternator. Following the data; 14V-12V= 2V at 60A shouldn't be too much for that wire??
On to the Oil Cooler Repair...
-Tim
Depending upon the wire's insulation, I think that #10 AWG wire is only good for about 30 amps, although I don't have an ampaciy table on hand (travelling this week). In any event, it would be wise to check this out and use a wire size that is matched to the fuse. Otherwise, the wire may wind up "protecting the fuse"! Not a good situation when the insulation on the wire breaks down and shorts the circuit.
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