Help, Alternator Hook up for the /6, I thought I had it right! - ZAP, ZAP.. Options

[DougC]

I have a problem where I get a major spark when attaching the battery cables to the battery. Clay Perrine pointed out to me that it's the heavy RED wire that's attached to the Starter (same place as the battery cable) and runs up to the back of the alternator. Clay suggested that this red wire was hooked to the wrong post on the altenator. OK, I removed the complete CIS injection unit and peeled back the engine shoud. The wires were hooked up to the alternator like in Wayne Dempsy's book, the pictures I took upon disassembly were lost so I had to use the book for this. I'm using a newly rebuilt Marchall alt. with external regulator. Here's a breakdown of how I have it wired:

(posts are clockwise from the top)
"+G1" or "+61" = blue wire
"B+" = Red wires [one thick, one thinner]
"another B+" = short ground strap from engine case
"DF" = black wire with spade end
"D-" = 3 small brown wires
"D." = un-used

Where have I gone wrong?

Doug C

[Porsche Rescue]

I recently wired a Bosch alternator on my six conversion. If you have a B+ grounding to the case, that is your problem. My alt. has 2 B+ terminals but only one is used, red wire to starter terminal. The case ground wire attaches to the alternator body on one of the studs for the plastic air guide. You are shorting the alternator/battery direct to the case.
On mine, the other three wires (D+, D-, DF go to their respective terminals on the relay board (three terminal plug) or direct to the regulator.

[DougC]

Jim, I moved the ground to the fan frame body just to see if the same sparks flew when attaching to the battery and the same thing happened. I did not have the plastic piece on the back of the alternator though, it may insulate the ground or something..ya think? Could I have fried the red wire and rendered it inoperable, I did see a small puff of smoke at the alternator then touching the cables to the battery.

Doug C

[Porsche Rescue]

Sorry, but I am not too knowledgable on electrical stuff. Maybe someone else will chime in. I do know that the B+terminal is the hot one which carries the alternator output to the battery via the starter terminal/+ battery cable. When you connected the battery cable you were sending battery current direct to the engine case. What I don't know is if you damaged the alternator in the process (hope not).

The plastic would not affect the ground. It just needs to be metal to metal, alternator stud to engine case.

One sign of a bad alternator is the dash light remaining on when the ignition key is off and going out when key is on, exact opposite of what should happen. Haynes says this is a symptom of bad regulator but in my case it was bad diodes in the alternator.
Are the wires to the relay board correctly connected (or are you not using relay board?)? If using the board, the D+ goes toward the front of the car, DF to rear and D- (ground) off to the outside (3 prong plug). If you are wiring direct to the regulator with the connector plug, you must reverse the D+ and DF by switching their position in the connector.

[DougC]

I'm using the relay board..and the connector to it has three wires, a blue - black - and a red. The black one has to connect to the "DF" on the alt because it's the only wire with the quick connect end. The red wire, I assume is the smaller one that's getting connected to the "B+" with the slightly larger red that goes to the starter. And the blue wire is connected to the "+61" at the top of the alt.

Doug C

[Cap'n Krusty]

"B+" is "B+". Why would you EVER hook it up to ground? If you're REAL lucky, you didn't blow any diodes, but I wouldn't bet on it. The Cap'n

[Porsche Rescue]

The small red is the D+ and does not connect to B+. It goes from another small terminal on the alt. to the relay board (regulator). Since I have a Bosch alt., it appears things are labeled a bit differently. On my Bosch alt. it is marked D+
I can't be certain, but the 61 blue must be ground, since the black must be DF.
There should be another terminal on the alt. for the small red D+. I am quite sure it does not connect to the B+ terminal. Could the "unused" D be the D+ for the small red wire?
Again, I only have 4 wires from my alt., large red to starter, small red to D+ on board, and two others (DF and D-) but I can't remember their colors. Plus the ground to the engine case from alternator body.

[Porsche Rescue]

I just looked at Dempsey's book, page 26. Totally different than my Bosch. It does look like both red's are connected to B+, nothing to D- (?) and green, black and brown (ground?) to other terminals. I think I am out of my league here.
Any chance that the alternator has an internal regulator? I think the change occurred around 1980 but not sure.
I don't think a standard 914 relay board/voltage regulator would be directly compatible with the wiring scheme shown in the pic. I will page Cap'n Crusty, sixnotfour, ArtechnikA on this. I suspect one of them has the answer.

[ClayPerrine]

Doug,


Start with unhooking everything but the big red wire and the ground. Does it still make sparks? If not, check how the regulator wiring hooks up.

Wish I was in town so I could come over and help you out.

[Kerrys914]

My turn (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif)

"/61" = thin blue wire (To Alt charge light from the VR connector)
"B+" = Red wires (one thick, one thinner) One to the VR connector and one to the Starter)
"DF" = Green (I think) wire with spade end (Brushes to VR connector)
"D-" = 3 small brown wires and Ground to case (to VR connector)

[Root_Werks]

QUOTE (Kerrys914 @ Oct 3 2005, 10:21 AM)

My turn (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif) "/61" = thin blue wire (To Alt charge light from the VR connector) "B+" = Red wires (one thick, one thinner) One to the VR connector and one to the Starter) "DF" = Green (I think) wire with spade end (Brushes to VR connector) "D-" = 3 small brown wires and Ground to case (to VR connector)

Yup, 61 can also be D+ on some units.

Pretty much you just match up the terms on the alt and the reg. Then run a big red wire from B+ to the end of your starter term.

Doug, are you running your wires to the factory 914-4 relay board? If you are, be careful! They are backwards of what you would think when you hook them up.

[DougC]

"B+" is "B+". Why would you EVER hook it up to ground?

Thanks Cap'n (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) I feel much better now..Actually rethinking it, I'm not sure if that was true or not, I'm almost sure I had it going to the lower most stud on the body of the frame.. you're so right, I would have known better than that, surely. But maybe I did it accidently.

Kerry's suggested set up is exactly how mine was wired to the tee. Nothing to the "D"

Clay, I think I'll try your suggestion of unhooking all unnecessary wires to the VR tonight. That seems like a straight forward aproach. BTW, the 2 red wires (1 large,1small) both share the same round end connector, which tells me that they've always gone to the same terminal on the alt, so I'll have to snip the smaller one away.

Doug C

[Jeffs9146]

Here is a photo of my alt.

Jeff

PS: this is from a factory 6 not a late model transplant

[DougC]

Doug, are you running your wires to the factory 914-4 relay board? If you are, be careful! They are backwards of what you would think when you hook them up.

Dan, can you explain what you mean here? I am using a stock relay board (914/4)..

Doug C

[DougC]

Thanks for the picture Jeff. Unfortunately for me, yours seems to be the alt with an internal regulator - right? Mine uses an external one.

Doug C

[Jeffs9146]

QUOTE

yours seems to be the alt with an internal regulator - right?

Nope! This is an externaly regulated alternator! Factory 6 motor, I had this alt rebuilt and replaced the regulator at the same time! Works like a champ!

Jeff

[DougC]

Jeff, from looking at the picture it seems to have less terminals than mine. I had a picture just like that saved to a "nexdisk" electronic storage device - one day it just decided it wouldn't load any more and I lost alot of pictures and notes.

Doug C

[Porsche Rescue]

That is identical to the Bosch alternator I have in my 2.7 conversion, wired to the 914-4 relay board using the external regulator on the relay board.
I think Doug's problem is the fact that he has a different alternator which is wired a bit differently.
The three terminal female connector which plugs into the 914-4 relay board is marked on the top side with D+, D- and DF. With the Bosch you just make sure the right wires are in the correct holes on the connector (they are D+ forward, DF rear and D- , side). You only need to switch them (swap D+ and DF) if you are not using the relay board but rather connecting direct to the male terminals on the bottom of the regulator.

[Aaron Cox]

QUOTE (DougC @ Oct 3 2005, 12:25 PM)

Jeff, from looking at the picture it seems to have less terminals than mine. I had a picture just like that saved to a "nexdisk" electronic storage device - one day it just decided it wouldn't load any more and I lost alot of pictures and notes. Doug C

thats what blogs are for (IMG:http://www.914world.com/bbs2/html/emoticons/smilie_pokal.gif)

[Jeffs9146]

QUOTE

I had a picture just like that saved to a "nexdisk" electronic storage device - one day it just decided it wouldn't load any more

Have you tried speaking to some of the Photoshop Experts on this forum? You may be able to e-mail the file to someone and see if they can open it!

Just a thought!

QUOTE

I think Doug's problem is the fact that he has a different alternator which is wired a bit differently.

(IMG:http://www.914world.com/bbs2/html/emoticons/agree.gif)


Jeff