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stevedmc
08-20-2013, 09:16 AM
So a local owner has been having voltage problems for a while now. Last night we finally got around to replacing his alternator with one from a 1991 Saturn SL1. Fortunately this fixed his problem and the gauge now sits around 13 volts. Before it would hover around 8 volts. He was living with it but this week it got so bad that he had to jump start his car everytime he went somewhere.

One important note I need to mention is you need a CS 130 pigtail to make the Saturn alternator work. Last night we found out you can't get this at AutoZone or Oreilly's unless you special order it.

I gave him mine since this is his daily driver and he was in a bind. I've found the item on Amazon.com and eBay. I went ahead and ordered it from Amazon since my car has to be back on the road before Thursday.

Here is the link in case anyone needs one.

http://www.amazon.com/gp/product/B00062Z52A/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1

Greasy DeLorean Mechanic
08-20-2013, 09:26 AM
FWIW: Autozone 14785 (1985 Volvo 760) does not require a pigtail/plug (wires attach with ring terminals):

448

Disadvantage: not a stock item -- has to be overnighted in.

Glad Drew is back on the road, especially since the Delo is his *ONLY* car. Is it still running OK in all other areas?

Bill Robertson
#5939

stevedmc
08-20-2013, 09:38 AM
As far as I know everything else is fine, considering it is a Delorean. The thought of putting a volvo alternator on it did cross my mind but we were in a bind.

Do you have to swap pulleys or use a spacer for the volvo unit?

Greasy DeLorean Mechanic
08-20-2013, 10:13 AM
Motorola pulley fits -- don't know about Ducellier.

There are washers/spacers between the fan blades and the unit itself. I just swapped over whatever was on the Motorola. Pulley itself butts against the fan blades.

One thing I didn't like: the Motorola alternator had a plastic woodruff key. I replaced it with a metal one. The key is some metric size -- file a little material off a domestic key to fit.

Bill Robertson
#5939

NightFlyer
08-20-2013, 10:44 AM
Great info on this thread - thanks guys!

stevedmc
08-22-2013, 09:31 AM
I need to make a small amendment to the Saturn alternator cross reference. You need a CS130 pigtail to make the wiring work.

Painles 30707 is what I used last time.

http://www.amazon.com/gp/product/B00062Z52A/ref=oh_details_o01_s00_i00?ie=UTF8&psc=1

It costs a little over $20 for the part from Amazon. I originally didn't need this pigtail because I was replacing one of John Hervey's alternators which is based on the same CS130 alternator.

Hervey only uses one wire from the plug. The white wire is connected to the brown/yellow wire that connected to the old alternator. The red wire is clipped and doesn't need to be used, although some owners have actually connected this to the positive post on the alternator. I choose to run mine without the red wire.

novadmc
07-20-2015, 10:24 AM
The white wire is connected to the brown/yellow wire that connected to the old alternator. The red wire is clipped and doesn't need to be used, although some owners have actually connected this to the positive post on the alternator. I choose to run mine without the red wire.

sorry for drudging up an old thread. just 1 question, so excuse my ignorance. Im bolting my Saturn alternator back on today - whats the pro/con of attaching the red wire to the pos post of the alternator? what purpose does it serve (or not serve if left unattached as you opted to do, Steve)

stevedmc
07-20-2015, 10:27 AM
I've got no clue. I simply duplicated what Hervey was doing and it worked for me.

I am carbureted though. That extra wire could have something to do with Kjet.

Ron? We all know you suck but you do know how to make Kjet purr. Any ideas?

Boglin
07-20-2015, 11:08 AM
This post may shed a little light on the red wire:

http://www.yellowbullet.com/forum/showpost.php?p=2552470&postcount=2

EDIT:

This one is more helpful:

http://www.camaros.net/forums/showpost.php?p=988496&postcount=9

So there may be some benefit to running the red wire to the 12V junction under the coil cover. Attaching it to the back of the alternator would not seem to make any difference versus leaving it unconnected, though.

Ron
07-20-2015, 04:06 PM
The guy in the first link above is full...er, ah, inaccurate. The second is correct except the use of the sense wire...

The best way to wire a SFLP alternator (marked on the case) is to hook the "L" terminal to the D's NY (Brown/Yellow) wire and the "S" terminal as close to the to the battery as possible (ideally, switched and fused, but not required).

Connecting the "S" terminal to the Battery/Output terminal-
Pros:
-Easy to understand and wire.
Cons:
- The regulator will keep the alternator at ~14.2v, but due to a 1v drop, the battery will be at ~13.2v. ~OK, but not ideal.

Connecting the "S" terminal to the Battery (or Main accessory feed. EG starter solenoid main terminal on most cars, especially older ones)-
Pros:
-The regulator will hold the alternator at ~15.2v at the alternator and ~14.2v at the battery (or junction). Ideal!
- Eliminates Battery light flashing v/s not hooking it up at all.
Cons:
-Harder to understand and wire.
- Increased battery life
- May void warranty since YOU changed the suggested wiring.......

Simply put, the regulator will cause the alternator to bring whatever is connected to the "S" terminal to 14.2v
Note you would not want to connect it to a random point or you risk it taking the voltage too high (or low) in other circuits etc!
The battery is best...unless you have an VERY long feed wire supplying a buss, in which case you would need to verify the voltage for all the circuits.

Bitsy started a thread on Talk (http://dmctalk.org/showthread.php?12181-DMCH-alternator) which covers this in detail if you need/want more info -- Or ask and I will try to explain better...

Boglin
07-20-2015, 04:45 PM
The battery is best...unless you have an VERY long feed wire supplying a buss, in which case you would need to verify the voltage for all the circuits.
.

It's probably a toss-up as to whether you value charging the battery more, or the optimal operation of all of the circuits, but if the latter, the sense wire would seem to be best placed at the point furthest downstream from the battery to where all circuits connect. The most practical location would be the main +12V junction under the coil cover, since this is where all of the circuits pick up +12V prior to any further bifurcation of the bus. In this way, the only component that will have a voltage higher than +14.2V will be the alternator.

If you instead run the sense wire to the battery and have a thick cable running from the alternator to the aforementioned main +12V junction, then it's likely all of the circuits will be seeing +15V or more at their input due to the length of the wiring from the alternator to the battery. Is that OK? Maybe. Hopefully the voltage will be reduced at each electrical device by the time it passes through the dirty fusebox. :)

Where are you getting the "1V drop" from (seems arbitrary), and also what warranty are you referring to (that may be voided)?

novadmc
07-20-2015, 04:56 PM
found this earlier today.
5440

stevedmc
07-20-2015, 05:09 PM
I don't know anything about that extra wire mumbo jumbo but for what it's worth, my car runs.

Ron
07-20-2015, 05:27 PM
FYI-

The older Delco 10 & 12 SI alternators can be used in the same manner (I use a 12SI @ 78A)-

Note they only have three terminals, Battery/Output, "1" or "F", and, "2" or "R".
-The "1" or "F" (Field/Exciter) connects to the N/Y wire.
-The "2" or "R" (Remote sensing) connects to the Battery (+), as with the "S" terminal above.

Boglin
07-20-2015, 05:29 PM
found this earlier today.
5440

So by "the same circuit", I assume it means downstream of any relay that would power the coil - so that you cannot short-circuit the main relay that would normally shut off the coil circuit.

NightFlyer
07-20-2015, 05:34 PM
http://www.trademarkia.com/logo-images/ducellier--cie/ducellier-73207054.jpg

Ron
07-20-2015, 05:51 PM
Matt,
It's not an either or situation because of the voltage drop you asked about... If you sense it at the battery it will be as you said, "the only component that will have a voltage higher than +14.2V will be the alternator". That is not a problem (note that the manual calls 13.5v minimum!). Other devices will not have too much voltage because their circuits will have a drop over their wiring as well...not arbitrary, but the reasoning behind it all. See?

RE: What warranty? ...Any, eg DMCH ..they supply a plug and directions. If you don't follow them, you ar at their mercy ;)

novadmc,
:thumbup:

Ron
07-20-2015, 05:56 PM
So by "the same circuit", I assume it means downstream of any relay that would power the coil - so that you cannot short-circuit the main relay that would normally shut off the coil circuit.It means ANY connection up/downstream connected to the same wire feeding the coil (w/o being switched).
EG a White wire off of the AUX relay.

novadmc
07-20-2015, 06:13 PM
Matt,
It's not an either or situation because of the voltage drop you asked about... If you sense it at the battery it will be as you said, "the only component that will have a voltage higher than +14.2V will be the alternator". That is not a problem (note that the manual calls 13.5v minimum!). Other devices will not have too much voltage because their circuits will have a drop over their wiring as well...not arbitrary, but the reasoning behind it all. See?

RE: What warranty? ...Any, eg DMCH ..they supply a plug and directions. If you don't follow them, you ar at their mercy ;)

novadmc,
:thumbup:

So bottom line, and to make sure I'm not totally dense (always a possibility), for a quick, no fuss no muss setup, just connect the red wire to the alt with the 6 brown wires and call it a day.

Greasy DeLorean Mechanic
07-20-2015, 06:15 PM
RE: What warranty? ...Any, eg DMCH ..they supply a plug and directions. If you don't follow them, you ar at their mercy

Paging Autozone....

(Lifetime warranty).

Bill Robertson
#5939

Bitsyncmaster
07-20-2015, 06:22 PM
The alternator delivers all the power the car needs as long as it's voltage is above battery voltage (12.5 volts). So the rest of the alternator current flows to the battery when it is not fully charged. When it is fully charged very little current flows in that battery wire and therefor very little voltage is dropped over the battery wire.

So putting the sense line on the battery + terminal could bring the rest of the cars electrics high when the battery is low on charge and the higher currents are causing a voltage drop on the battery wire.

I've found testing an extra battery that 13.5 volts can push 30 amps into the battery if it is low on charge but that same 13.5 volts only charges 0.3 amps on a fully charged battery. Those test are at room temp (77 deg F) so at colder temps that voltage may need to go higher.

Ron
07-20-2015, 06:28 PM
Paging Autozone....

(Lifetime warranty).

Bill Robertson
#5939
""Warranty excludes damage caused by misuse, abuse, other faulty parts, improper installation or off-road, commercial or marine use.""
But, yeah, who is going to tell... :D

Greasy DeLorean Mechanic
07-20-2015, 06:36 PM
You know as well as I do that you could set the thing on fire and Autozone would still take it back.

I prefer Autozone's warranty over Advance's because Advance only keeps record of your purchase at the store where you bought the part, and even then only for 12 months. Without a receipt in hand you're pretty much screwed if you try to replace a part somewhere else, or sometime later.

Autozone has record of my purchases all the way back into the 1990's (nationwide).

Bill Robertson
#5939

Ron
07-20-2015, 06:40 PM
You know as well as I do that you could set the thing on fire and Autozone would still take it back.
Bill Robertson
#5939Yeah...as long as you don't tell them that is what you did, LOL

Ron
07-20-2015, 08:51 PM
So bottom line, and to make sure I'm not totally dense (always a possibility), for a quick, no fuss no muss setup, just connect the red wire to the alt with the 6 brown wires and call it a day.Yes, but you are going to hate me...the jury is still out.
So far the quick, the no fuss no muss setup is as Matt said, connect it to the main junction under the coil cover -- It has benefits and we all seem to agree it is better than connecting it to the alternator output terminal (which will do nothing since the regulator has that connection internally), except make the light quit flashing for some alternators.

=======

Dave, I don't see where you are allowing for a drop from: the feed wire to the main terminal junction => wire to AUX Relay => AUX Relay(s) =>wiring to Fuse panel => Fuse(s) =>wiring to control(s), if any => control(s) => wiring to device(s). It has to be more than the difference between the two places. ...Weak battery or not, I don't see how it could go too high, especially since we have to consider the difference (ie there is a drop from the junction/solenoid/batt cable/wherever it connects too....ot could only be too high by the difference, not to mention the load(s)... ).
FWIW- I know GM ran the vast majority of theirs to the solenoid or fused link right off of the (+) cable for decades (SI alternators). Only ~3' of relatively huge copper wire difference to consider there...
And, after a very long sit, I've checked my D right after it grunted to barely start, but have never seen it too high?? I don't see why any of the manufacturers would waste the bucks on a plug and wiring if there was no benefit when they could just pick it up internally (as GM did with some of the old non-AC equipped systems)...
:dunno:

=======

A simple test for anyone to see for themselves would be to connect the wire with an alligator clip to the output terminal , main junction, battery (+), with the battery low and fully charged, then compare.

P.S. Steve SUCKS!

NightFlyer
07-20-2015, 09:01 PM
P.S. Steve SUCKS!

What about me?

Ron
07-20-2015, 09:09 PM
What about me?Paging Steve...

Greasy DeLorean Mechanic
07-20-2015, 09:31 PM
I feel so left out -- my Volvo alternator only has two terminals: B+ (output) and D (warning light/field excitation).

Bill Robertson
#5939

NightFlyer
07-20-2015, 09:38 PM
I feel so left out -- my Volvo alternator only has two terminals: B+ (output) and D (warning light/field excitation).

Bill Robertson
#5939

My Ducellier alternator requires no modifications to the awesome Lucas wiring what-so-ever :biggrin:

Bitsyncmaster
07-21-2015, 03:40 AM
I would have though the sense terminal is internally connected to the + output of the alternator also with a resistor. But on the new DMCH alternator that is not the case since that sense pin has no voltage on it when not connected.

It must be the new DMCH alternator has one of those new smart regulators (a microprocessor runs it). Connecting my sense pin to the + output stud stopped it from flashing the error code and stopped that voltage dip every 18 seconds.

My car has new large gauge wiring in the battery alternator circuit so I'm not that concerned with voltage drops. It also looks like this alternator as well as many others have the voltage output set to 14.8 volts (which it says on the data sheet that came with the alternator). I would not want any voltage in the electrical system to go much higher than that 14.8 volts.

Bitsyncmaster
07-21-2015, 04:06 AM
Here is a wire resistance calculator:

http://www.cirris.com/learning-center/calculators/133-wire-resistance-calculator-table

Let's just say as in my case I have 6 foot of #4 AWG wire from the alternator to the +12 feed in the ignition coil bulk head bolt. Also lets say my car is drawing 60 amps (running lights, blower and AC) and right after I start the car it is pumping 40 amps into the battery to restore the power it used during engine start. So there is a 100 amps flowing over that 6 foot of wire.

So I have 0.001 ohm of resistance in that wire. Voltage drop is current times resistance. So I'm dropping 0.10 volts at that max current. So with my sense line at the alternator, I get 14.7 volts at the bulkhead where as if I had the sense line at the bulkhead I would have 14.8 volts there.

Of course if your car has smaller wire gauge your drops will be a little more.

dustybarn
07-21-2015, 07:22 AM
It must be the new DMCH alternator has one of those new smart regulators (a microprocessor runs it). Connecting my sense pin to the + output stud stopped it from flashing the error code and stopped that voltage dip every 18 seconds.



Hmm.... I wonder if that 18 seconds corresponds to some sneaky RC time constant that comes into play when the sense terminal is allowed to float.

stevedmc
07-21-2015, 09:13 AM
Paging Steve...
My car runs. I still don't understand all the nonsense over that extra wire.

I've driven from here to South Carolina several times. Driven to Atlanta and back. Driven to Orlando. Kentucky, Ohio, Chicago, West Virginia and a bunch of other places. All with that stupid wire clipped.

Not once did I have any power failures other that losing alternator belts on the side of the highway in Mississippi and Kentucky. Even at that, I pulled over, changed the belt and I was on my way.

Bitsyncmaster
07-21-2015, 09:20 AM
Hmm.... I wonder if that 18 seconds corresponds to some sneaky RC time constant that comes into play when the sense terminal is allowed to float.

It's probably something in software reporting an error message. The timing is exactly 18 seconds and to consistent.

novadmc
07-21-2015, 09:53 AM
My car runs. I still don't understand all the nonsense over that extra wire.

I've driven from here to South Carolina several times. Driven to Atlanta and back. Driven to Orlando. Kentucky, Ohio, Chicago, West Virginia and a bunch of other places. All with that stupid wire clipped.

Not once did I have any power failures other that losing alternator belts on the side of the highway in Mississippi and Kentucky. Even at that, I pulled over, changed the belt and I was on my way.

what i take away is that it seems the wire can either be attached to B+ on the alternator or left unattached completely with no ill effects in either manner.
But the current "best" agreed upon placement would be to run it to the junction under the coil cover (where exactly, what specific wire, etc i dont know, since im still learning to make heads or tails of the color wiring diagram :) )

Ron
07-21-2015, 10:02 AM
I was wondering if I could find out how much the regulators would actually allow the voltage to go beyond their set points. While going through some docs I didn't find that (yet), but I did find some useful info: It looks like the standard GM internal regulators usually had a 14.2v set point, with many 14.8v. The most common for PLIS alternators (CS121, CS130, CS144, ...) are 14.7v and 14.8v. The lowest I spotted for any unit was 14.1v.
I spotted the below and believe it will shed some light on the later alternators operation, the mysterious flashing light, and where it expects the (S)ense wire to be connected.
(Note I do not know if this is what is used in the exact alternator in question. If its specs mention Load Response Control (LRC), I would highly suspect so -- Just food for our thought pot at this point ;-)

5444

Dracula
07-21-2015, 10:06 AM
My car runs. I still don't understand all the nonsense over that extra wire.

I've driven from here to South Carolina several times. Driven to Atlanta and back. Driven to Orlando. Kentucky, Ohio, Chicago, West Virginia and a bunch of other places. All with that stupid wire clipped.

Not once did I have any power failures other that losing alternator belts on the side of the highway in Mississippi and Kentucky. Even at that, I pulled over, changed the belt and I was on my way.

I, too, have traversed the country with the same wire disconnected and have had no problems.

Ron
07-21-2015, 10:09 AM
My car runs. I still don't understand all the nonsense over that extra wire.

I've driven from here to South Carolina several times. Driven to Atlanta and back. Driven to Orlando. Kentucky, Ohio, Chicago, West Virginia and a bunch of other places. All with that stupid wire clipped.

Not once did I have any power failures other that losing alternator belts on the side of the highway in Mississippi and Kentucky. Even at that, I pulled over, changed the belt and I was on my way.Don't worry about it then -- The alternator defaults to looking at the power from the main terminal (internally) if you don't hook up the "extra" wire. Like I said earlier, it's not the best, but OK.

P.S. NF has something he wants to ask you...

stevedmc
07-21-2015, 10:12 AM
This thread reminds me, I need to bypass my ballast resistor as well. I think I heard about someone on Facebook (or maybe it was Talk, I don't know) saying something about their resistor grid having the exact same issue as Bill's recently had.

Ron
07-21-2015, 10:32 AM
:popcorn:

Dracula
07-21-2015, 10:50 AM
This thread reminds me, I need to bypass my ballast resistor as well. I think I heard about someone on Facebook (or maybe it was Talk, I don't know) saying something about their resistor grid having the exact same issue as Bill's recently had.

So far, I've put over 50 miles on mine without the ballast resistors.

Greasy DeLorean Mechanic
07-21-2015, 10:47 PM
All resistors (such as oven elements, hot water heater elements, and even electric carburetor choke caps) burn out eventually.

Bill Robertson
#5939

NightFlyer
07-21-2015, 11:15 PM
All resistors (such as oven elements, hot water heater elements, and even electric carburetor choke caps) burn out eventually.

Bill Robertson
#5939

5450

NightFlyer
07-21-2015, 11:36 PM
P.S. NF has something he wants to ask you...

For some reason, Ron really wants me to ask Steve if 30 seconds is normal, as last night, Ron completely failed to satisfy me, if you know what I mean.... :fina:

NightFlyer
07-22-2015, 12:09 AM
For some reason, Ron really wants me to ask Steve if 30 seconds is normal, as last night, Ron completely failed to satisfy me, if you know what I mean.... :fina:

Hmmm, jokes such as the one made above can lead to something like this happening here....

http://dmctoday.com/showthread.php?1446-The-cat-s-finally-out-of-the-bag!&p=30859&viewfull=1#post30859

Ron
07-22-2015, 12:51 AM
Found it, finally (for all SI alternators anyway):

54555453

So we can hook the "S" wire at the battery or junction (basically anywhere, or nowhere, lol), as long as the difference in Batt v/s Alternator voltage does not exceed 0.5V at maximum output (6000 alternator RPM, NOT engine engine RPM).

NightFlyer
07-22-2015, 01:06 AM
Found it, finally (for all SI alternators anyway)

Good find :thumbup:

Ron
07-22-2015, 01:35 AM
For some reason, Ron really wants me to ask Steve if 30 seconds is normal, as last night, Ron completely failed to satisfy me, if you know what I mean.... :fina:It is obvious that that is not what I was talking about since the post was 11:09 AM yesterday -- I was talking about this:

What about me?
You have to ask him...I gave him his own pimp suit long ago (it's green).

As for last night, I said my 30 centimeters was a lot longer than normal, which I assume Steve can confirm, but don't tell him I want to know, because I think he SUCKS!

=======

(Go ahead)':fina: {Damn!...what the hell was he doing during his absence??}

NightFlyer
07-22-2015, 02:46 AM
As for last night, I said my 30 centimeters was a lot longer than normal...

I see that we're still multiplying by a factor of 3....

Ron
07-22-2015, 02:50 AM
Damn, that's what she said too!

novadmc
07-22-2015, 05:22 AM
So we can hook the "S" wire at the battery or junction (basically anywhere, or nowhere, lol), as long as the difference in Batt v/s Alternator voltage does not exceed 0.5V at maximum output (6000 alternator RPM, NOT engine engine RPM).

Nice find! For now I have "S" directly connected back to B+ on the alternator. But I do plan to connect it to the batt down the line as I do more electrical upgrades.

On a side note, the old alternator had that extra single brown wire connected to it (went from a "+" spade connector to an aux relay according to the wiring diagram). What was the purpose of that wire/connection even tho I no longer need to use it?

DMC5180
07-22-2015, 09:00 AM
Nice find! For now I have "S" directly connected back to B+ on the alternator. But I do plan to connect it to the batt down the line as I do more electrical upgrades.

On a side note, the old alternator had that extra single brown wire connected to it (went from a "+" spade connector to an aux relay according to the wiring diagram). What was the purpose of that wire/connection even tho I no longer need to use it?

If you have the 81 style engine harness where the alternator wires go over the top of the engine, you still have the brown (sense) wire. When the factory switched to the Motorola (one-wire) alternator, they just snipped the brown wire near the alternator and stowed it in the harness. If you unwrap the harness starting at the point where the brown/yellow wire appears from the harness wrap, you should find it near there. Splice on an extension wire and you should be able to use it.

novadmc
07-22-2015, 10:13 AM
ha, so rather than having the red "S" wire from the CS130 pigtail connect to B+, i can optionally just connect "S" to that brown sense wire. (even tho directly to the batt or junction would still be best)

DMC5180
07-22-2015, 12:38 PM
Yes

The advantage of the brown wire is that it is switch sourced and provides a voltage dropped reference. Make sure the bulkhead connections are clean too.

novadmc
08-01-2015, 12:43 PM
hooked up my multimeter directly to the battery on my way home from Cars & Coffee today to see how the new alternator is performing (and after replacing all the fuses as noted in the other thread i started).
Volt needle still goes below 13 when AC is on (normal AC, fan set to 3, when idling, on the brakes at a stop light) but voltmeter read 13v. lowest reading was 12.75 briefly before jumping back to +13v.
When i lift off the brakes at a stop with AC going, voltage goes to 13.5v or higher (13.8v, etc).
While in motion and above 1500rpm, voltage never dipped below 13.5v with AC, and lights on.

Overall im happy with the more stable 13v range voltage. and the needle doesnt bounce around as much as it did. :thumbup:
That said, i've ordered a set of the LED tail light boards from DMCH to see if that clears up the .5v or greater dip i see when at a stop and pressing the brakes (and just because upgrades!). also ordered Hervy's battery ground kit to see if that makes the volt gauge on the dash any more accurate, as well as to simply provide a better ground for the battery overall.

Ron
08-01-2015, 11:37 PM
Overall im happy with the more stable 13v range voltage. and the needle doesnt bounce around as much as it did. :thumbup:So, curious how you wind up wiring it? ( I didn't spot it if you ever said...)

novadmc
08-02-2015, 05:44 AM
For now it's still wired up to B+ on the alternator. simply because i was lazy and pressed for time and wanted to get the car back up and running. (then ended up going out of town for a few days last week so i didn't have time to wired it more "correctly")

In the future, i do plan on changing out the ring terminal on the sense wire and connecting a spade connector and then connecting it to the sense (brown) wire i'm now not using (since i have the earlier 81 style wiring harness and still have that wire as it was used with the old alt). then i'll try wiring it directly to the + on the battery (should i fuse that when i do that?). when i get around to it i will report back what voltages read.

Ron
08-02-2015, 06:55 PM
then i'll try wiring it directly to the + on the battery (should i fuse that when i do that?).I would, but it seems DMC didn't worry about unswitched hot wires running all over the place:

5541:rolleyes:

DMC5180
08-02-2015, 07:32 PM
Although it's not shown in that schematic, the original brown sense wire originated from AUX relay distribution junction. It's The cluster of white wires protruding from the main harness in the relay area next to the main / aux relays.

Ron
08-02-2015, 08:15 PM
Although it's not shown in that schematic, the original brown sense wire originated from AUX relay distribution junction. It's The cluster of white wires protruding from the main harness in the relay area next to the main / aux relays.
Yes -- And one of those white wires goes straight to the ignition feed, which some of the alternators have warnings against using (else you may not be able to turn off the engine), as previously mentioned.
(I don't like the potential for noise on those circuits anyway...)

novadmc
08-02-2015, 10:10 PM
Yes -- And one of those white wires goes straight to the ignition feed, which some of the alternators have warnings against using (else you may not be able to turn off the engine), as previously mentioned.
(I don't like the potential for noise on those circuits anyway...)

I even think the autozone alt has that warning in its paperwork. i'd have to dig it out to confirm though.

If/when i run directly to the batt, what size amp fuse would you recommend?
I assume 16/18ga wire is fine for the job since its just volt sensing (and that's what the sense wire already is)

Bitsyncmaster
08-03-2015, 04:14 AM
So is the Saturn alternator voltage set at 13.5 volts? My Hervey and DMCH alternators are set for 14.6 volts. From some battery testing I've been doing, 13.5 volts at the battery seems enough to keep the battery fully charged if you are doing long drives.

Greasy DeLorean Mechanic
08-03-2015, 06:32 AM
Every alternator I own, from the DeLorean to my school bus, puts out around 13.5 volts. That is more than enough to keep the battery charged in normal driving (two batteries on the bus).

Bill Robertson
#5939

Bitsyncmaster
08-03-2015, 07:41 AM
Every alternator I own, from the DeLorean to my school bus, puts out around 13.5 volts. That is more than enough to keep the battery charged in normal driving (two batteries on the bus).

Bill Robertson
#5939

Just checked my 2005 Malibu and it puts out 14.48 volts on the battery terminals.
My 2003 Impala puts out 14.73 volts on the battery terminals.

These are cold start temps at idle speed without accessory's on. Note the DRL lights are on.

Wonder when and why alternator setting voltage has increased.

novadmc
08-03-2015, 10:37 AM
Just checked my 2005 Malibu and it puts out 14.48 volts on the battery terminals.
My 2003 Impala puts out 14.73 volts on the battery terminals.

These are cold start temps at idle speed without accessory's on. Note the DRL lights are on.
.

when first fired up cold, the Saturn alt did/does put out 14+v to the battery. It gradually went/goes into the mid 13's and stayed/stays there (no accessories on) once warmed up though (observed over a period of ~5-10 mins).

Boglin
08-03-2015, 03:33 PM
So I ordered the Painless wiring pigtail so I can experiment with the Sense wire and the determining the effect on charging voltage (was using the SpecialT pigtail all this time).

Ron
08-03-2015, 08:15 PM
If/when i run directly to the batt, what size amp fuse would you recommend?
I assume 16/18ga wire is fine for the job since its just volt sensing (and that's what the sense wire already is)
Yes, match the wire size.
Fuses are for wire protection... Put it next to the battery. If it's 16ga, max fuse size is 7.4A max. 18ga 4.6A max.
It draws next to nothing and believe me if you hook that puppy up wrong, it is toast, instantly --very unforgiving!


So is the Saturn alternator voltage set at 13.5 volts?
Of the 5 regulators in a remanufactures catalog 1 is 13.7V, 3 are 14.7V and 1 is 14.8V. Depends on year etc.
GM/CSxxx/other set point info in post #36.


Every alternator I own, from the DeLorean to my school bus, puts out around 13.5 volts. That is more than enough to keep the battery charged in normal driving (two batteries on the bus).

Bill Robertson
#5939Kinda throwing me a bit with "around" and "more than enough", but , yeah, 13.5 minimum, at the battery, is usually OK.

novadmc
08-03-2015, 09:35 PM
Yes, match the wire size.
Fuses are for wire protection... Put it next to the battery. If it's 16ga, max fuse size is 7.4A max. 18ga 4.6A max.
It draws next to nothing and believe me if you hook that puppy up wrong, it is toast, instantly --very unforgiving!


ha, no pressure to get it right or anything ;)

this evening i installed DMCH's LED tail lights and Hervey's battery grounding kit. later this week when i drive the car, ill see what, if any difference that makes to the alternator.
I'm out of 18ga wire and also need to go pick up an inline fuse holder before redoing the sense wire.

Ron
08-03-2015, 09:53 PM
ha, no pressure to get it right or anything ;)
LOL ...I just remember the days when a spark or two made one grin, not (hopelessly) pray.

Boglin
08-06-2015, 05:06 PM
So with my new painless wiring pigtail, I attached the sense (S) wire to the bulkhead +12V post, and then measured the voltage between the said post and the engine block with the car running.

55645565

EDIT: This was with the AC on, headlights on, and stereo on.

novadmc
08-07-2015, 07:07 AM
What was the reading without the sense wire attached?

Boglin
08-07-2015, 07:30 AM
What was the reading without the sense wire attached?

Beats me. Why don't you measure yours at the bulkhead as a comparison? :)

Bitsyncmaster
08-07-2015, 07:40 AM
Beats me. Why don't you measure yours at the bulkhead as a comparison? :)

Are you running the Saturn alternator? If so it looks like the sense wire does bring up the voltage.

Boglin
08-07-2015, 07:41 AM
Are you running the Saturn alternator? If so it looks like the sense wire does bring up the voltage.

Of course I'm running the Saturn/Autozone alternator!

Andrew
08-11-2015, 08:49 AM
Does anyone have a part number for the Saturn / GM alternator plug? I'm planning on upgrading 5052 to the Saturn unit in the upcoming weeks.

Boglin
08-11-2015, 08:51 AM
Does anyone have a part number for the Saturn / GM alternator plug? I'm planning on upgrading 5052 to the Saturn unit in the upcoming weeks.

First post of this thread has it from Amazon (Painless Wiring).

Chris 16409
08-11-2015, 05:46 PM
Dorman 85118 is also another option. It appears to be cheaper. You can pick it up at a local auto parts store.

http://www.autozone.com/1/products/40754-voltage-regulator-connector-dorman-85118.html

Bitsyncmaster
08-11-2015, 06:51 PM
Why do they use a 10 AWG wire on the voltage sense wire (RED)?

Boglin
08-11-2015, 08:13 PM
Why do they use a 10 AWG wire on the voltage sense wire (RED)?

Beats me, Dave! Seems like it would be a high impedance input, right?

Bitsyncmaster
08-12-2015, 05:02 AM
Beats me, Dave! Seems like it would be a high impedance input, right?

Yes it is micro-amps of current so you get no voltage drop over any small gauge wire. Only thing I can think of is some alternators use that sense terminal for high currents to start the field current.

Andrew
08-12-2015, 08:27 AM
It turns out that 5052 doesn't need an alternator, in contrast my dashboard voltage gauge it horribly miscalibrated! Yesterday via my multimeter I confirmed that despite the fact that my gauge was reading in the 9-10 volt range with all accessories on (including stock cooling fans), the actual voltage at the alternator was in the 12.4 volt range. I compared it with the voltage readings on 4194 and confirmed similar readings...4194's gauge reads just under 13 volts with the same load.

The moral of the story is don't trust the stock gauge and when in doubt always verify with an accurate multimeter.

Thanks to everyone who helped with the plug cross reference! I'll be upgrading to the Delco unit if the stock Motorola ever does fail.

Boglin
08-12-2015, 08:32 AM
12.4??!???

Andrew
08-12-2015, 08:43 AM
That was with cooling fans, a/c fan at 4th speed, low and high beams, hazard flashers and wipers.

Bitsyncmaster
08-12-2015, 08:55 AM
12.4 at the battery is not enough to charge it. But if your higher most of the time (not so many loads and cruising) then you should be OK. Just if you don't take long drives your battery may not get charged.

Boglin
08-12-2015, 09:45 AM
I think I would swap that alternator. If you get stuck in traffic, you will feel like it's a race against time to get back up to charging speed (cruise).

Chris 16409
10-11-2016, 02:31 AM
Most of these Saturn Units only output around 96 Amps. Thats a little on the low side? Is anybody seeing any issues? I know 105 Amp versions exist, just not sure what car they are listed under.

Boglin
10-11-2016, 04:34 AM
Most of these Saturn Units only output around 96 Amps. Thats a little on the low side? Is anybody seeing any issues? I know 105 Amp versions exist, just not sure what car they are listed under.

I blame SpecialTAuto for selling the idea that you need a 150-amp alternator for these cars.

Several owners have measured their current draw with every electrical component operating simultaneously (except the starter) and arrived at around 65 amps.

The Motorola OEM unit was rated at 90 amps.

I've been using the Saturn unit since 2014 with no trouble.

Ron
10-11-2016, 11:28 AM
I know 105 Amp versions exist, just not sure what car they are listed under.
91-97 (SC SI SW) with 1.9L engine (needs pulley swap), IIRC.

stevedmc
10-11-2016, 12:32 PM
Mr Boglin sells a nice mount for installing those saturn alternators too.

Sent from my SM-G900V using Tapatalk because I'm too lazy to turn off the mobile signature thingie on my phone.

Chris 16409
10-12-2016, 12:51 PM
I've got a friend who has a Volvo unit fitted and it's not cutting it. It may only be rated for 70 Amps. He told me the voltage drops very low when the cooling fans turn on. We'll try the saturn unit.

Rich_NYS
10-12-2016, 01:21 PM
Is the Saturn alternator better than Lou's 24V alternator?

stevedmc
10-12-2016, 02:21 PM
Yep.

Sent from my SM-G900V using Tapatalk because I'm too lazy to turn off the mobile signature thingie on my phone.

DMC5180
10-12-2016, 06:02 PM
Is the Saturn alternator better than Lou's 24V alternator?

24V ????


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stevedmc
10-12-2016, 08:14 PM
24V ????


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Rumor has it that Lou used to have a diesel alternator in his car.

Chris 16409
12-17-2016, 10:23 PM
Do you know if an impact drill is required to remove the nut for the pulley swap? That's how I've had it done at the autoparts store. Can a breaker bar be used?

Boglin
12-17-2016, 10:47 PM
Do you know if an impact drill is required to remove the nut for the pulley swap? That's how I've had it done at the autoparts store. Can a breaker bar be used?


The difficulty is in preventing the pulley/fan blade from rotating while using a breaker bar. If you made a jig that could apply pressure equally to all of the fan blades, or built some kind of clamp for the pulley that would not distort the grooves, then there is no reason you couldn't use a breaker bar.

It's much easier to use an impact wrench, though.

Chris 16409
12-22-2016, 04:36 PM
I got the pulleys off okay, but then realized the V-Belt pulley on the old Alternator would not fit the Saturn Unit. The main shaft on the Saturn unit was a bit wider. Never the less, I was able to ream out the pulley bore to the correct size and got the alternator fitted. My new issue is the batter light in the dash isn't coming on. I bought the proper GM plug and wired it up to the thin brown wire with the yellow stripe. My guess is the battery light bulb has burnt out. The funny thing is, the old alternator wasn't connected at all to either of thin brown or brown/yellow wires. I'm not sure how it was charging the battery then. It must have used some weird wiring circuit. I'll include a picture of the old alternator.

8207

8208

Rich_NYS
12-22-2016, 06:29 PM
I got the pulleys off okay, but then realized the V-Belt pulley on the old Alternator would not fit the Saturn Unit. The main shaft on the Saturn unit was a bit wider. Never the less, I was able to ream out the pulley bore to the correct size and got the alternator fitted. My new issue is the batter light in the dash isn't coming on.

There's a way to test that light, I think you can ground the wire or something like that. I'll try to find where I saw that posted.

*Edit: I found the info Dave S. posted on Talk in reference to when I had a charging issue. "You can test the light bulb circuit. Take the light wire off the alternator and ground it. Turn the key on and see if the light comes on. If it does, the light circuit is good and regulator in the alternator is bad."

In your case, you might have the same situation I had where the lead was on the wrong plug position for the type of alternator I had.