Alternator Install

[Superman]

The small air deflector will not properly attach to my alternator/fan housing with my alternator sitting up (writing on the backof alternator not upside down...voltage regulator at the top). the deflector will fit with the voltage regulator on the bottom, but this means the writing on the back of the alternator is upside down. I assume this is okay.

I need somebody's help making sure I am not hooking the alternator up wrong. There is one big stud and two small studs. I know which wire(s) goes to the big stud. I just don't know which wires go to which of the two smaller stud terminals. My notes discuss "left and right" concepts but now I can't say for sure which way the alternator was oriented before removal/rebuild.

The back of my alternator is divided into three areas. Voltage regulator. kindney shaped area with a "+". Kidney shaped area with a "-". I believe both small studs come out of the area marked "-" while the larger stud comes out of the "+" side. I think. I'll look. Warren? John? Anybody that understand these alternator things?

[RoninLB]

I can't remember all the details. So in the Tech. Bull. 1, B+ is red wire, D- is brown[2 required], 61 is blue wire. The pic. shows term. 61 directly opposite the regulator. This info is for integrated reg.

[Early_S_Man]

hey, Super!

See your Parts and Technical Reference for the hard copy of these bulletins ... but it looks like the regulator goes down! And, the three terminals should be marked '61,' 'B+,' and 'D-' starting at the top and going clockwise!

[304065]

Super (Uber?):

This is an oldie but a goodie and one of my favorite subjects, 911 electrical systems. Check this thread and all will be revealed:

http://www.pelicanparts.com/cgi-bin/vb/showthread.php?s=&threadid=61757&highlight=d%2F61

On the Airguide- yes, the regulator is at the 6:00 position when the alternator is mounted in the shroud. The cutaway area of the Airguide is designed to clear the internally regulated voltage regulator, so that's why it's at the bottom. Warren's tech bulletin illustrates the cutaway, on the first page, the lower left corner, lower right picture.

Good luck, remember, if it smokes, something's wrong.

[Superman]

My Haynes manual is hiding from me again. Perhaps I shouldn't have said the things I said about it. Anyway, I need to know which color wires go on which terminals. My note clearly suggest that one big and one smaller red wire go to "B+". Of the two remaining terminals, one must be ground because there is a group of brown wires that go to it. Which is ground, "61" or "D-"? And the other terminal then gets a single, petite baby blue wire. Here's a clue: Terminal "D-" seems to be a connection coming off the voltage regulator.

Thanks a million, in advance.

[john walker's workshop]

ground is D-
the blue wire goes to D+/61

[304065]

I should have pasted this from the link:

You should have four wires:

DF (black) or "Dynamo Field" goes to tab "F" on brush holder

D+/61 (blue)- "Exciter" circuit from warning light- to "B"

B- (brown) "Ground"- goes to alternator case ground "E" or B- terminal

B+ (large red, or 2 large reds) "Hot" to terminal "C"

FYI according to TUV, the German technical standards organization, all ground wires must be Brown. Same on all German cars.


Good luck!

[Early_S_Man]

John,

'82 and later cars don't have an external regulator or Black 'DF' wire! See bulletin above ...

Also, in 1975 and later cars Porsche ... er, uh ... ignored the 'Brown = Ground' rule for the right tail-lamp assemlies and specifically, the oil tank level sender ground wire, and changed it to WHITE!

[304065]

Warren,

Right as usual-- for some reason I was thinking that Super had an externally regulated model despite that being the point of the thread in the first place and about four references to it. Must be all that lacquer thinner I'm using to clean the harnesses.

I am (painfully) familiar with the distinction between internally and externally regulated alt's: when I got the '71 it wasn't charging, so after going through all the circuits, and noting that I didn't have a voltage regulator on the console, I pulled the alternator, expecting to find an internally regulated one-- much to my surprise there was a good old Motorola external version-- I guess it's pretty hard to charge your battery without a voltage regulator. I think what happened is the prior "S" motor had an internally regulated alternator installed as an update at some point, but when the "E" was installed the PO didn't swap the alternators. I have subsequently converted to a Carrera alternator, which required machining of a new shroud (thanks to John Walker for the advice on that one)-- but now I'm having second thoughts and thinking about going back the other way. Something about seeing that "930. . . " casting number on the new shroud. . .

Hey, I like your point about the oil tank ground wire, maybe they figured it would turn brown from proximity to the oil tank.

JFC

[christiandk]

Guys could you help me out?

according to the books and writeups there should be 2 brown ground wires on my 82 sc. But as the picture shows there are only 1 set of brown wires but 2 red?

I suspect that the red wire that goes to the engine case has been replaced and should be brown?

Anyone?

[ManniB]

Christian,

the single red wire is, like you assume, engine ground and was brown from the factory. You can either connect it together with the other tree ground wires (brown) or, as I did, mount it to one (I opted to put it on the lowest stud that is left out by the air guide) of the attaching studs of the alternator.

Best, Manfred.

[yelcab1]

It looks like that ground wire to the engine case was replaced with a red one. That is the ground nevertheless.

[christiandk]

That is what I thought...thanks Manfred and yelcab