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Alternator/Headlight Upgrade

123K views 503 replies 89 participants last post by  kwilford 
#1 · (Edited by Moderator)
Oldopelguy,
Early in this thread you mentioned about upgrading the alternator using GM stuff as follows:

Well, since Bob brought up alternators....
I just borrowed a friends digital camera and I am taking some pictures of a simple way I use to back-fit Opel motors with a 60, 85, or even 140 amp GM alternator. I've even got the wiring figured out so the charge light on the dash will still work. I'll get the picture and some detailed drawings posted when I get them worked out enough to be presentable and double-check the parts fit into a GT. (What works in my Kadett or Manta only sometimes fits into a GT.)

I'd be very intrested in you sharing any info that you have on this upgrade. I want to upgrade my GT alternator and from what I've found out the GM Delco 10si style alternator is a great way to go. Internal regulator, good output even at low idle speed, well designed and cheap too. How did you do it? I'm all ears.
 
#52 · (Edited)
First off, by all means put in a hi amp fuse, the original wiring has a fuseable link at the alternator output, also there is one on the red wire at the starter where the battery cable hooks up and powers the whole system. If you don't have a DESTEC schematic or access to a wiring diagram, here's how the original charging system is hooked up. Output from the alternator goes via the red wire to a stud on the fuse panel, through the buss bar and out the other stud via the Red/White wire to the B+ stud on the amp gage. From the L+ stud on the amp gage via the Red wire back to the fuse panel stud opposite the stud that came from the starter. That setup gives total amperage indication + or - of the entire electrical system, because all power into and out of the battery and alternator goes through the amp gage. On the original alternator/regulator there are three wires into and out of them both. The only other wire is the Blue/White wire from the amp gage lite. That lite has "switch on" power to one side of it and alternator signal power on the other, This difference in voltage between the two sources of power lighting the lite is what signals the alternator to put out voltage/amps. When the alternator puts out anything close to system voltage the lite dims and as voltage going out increases, the lite goes out. If you do not have the lite in the charging system you will not get any alternator to function, it is the difference in system voltage and alternator voltage that makes the alternator work. In order for the single wire alternator to work, you have to have the Blue/white wire go to the plug on the alternator. If you hook up the alternator output to the starter terminal where the battery hooks up, you will not have any indication of charging or discharging, because you take the ammeter out of the circuit. By looping the wire from the alternator plug to the output stud, the alternator will see no difference in voltage and will not generate any output to the battery. HTH.
 
#53 ·
i'lm thumbing through the wires under the hood and i've realized something.

i have no blue/white stripe wire.

so.

coming from the 'bundle' of wires going towards the regulator and coil and what not:

red - stud on back of alternator.
green - coil/distributor
clear - coil (oppoisite side of green)
black (no color) goes to same post as said clear wire.

red wire to 3 wire pigtail that connects the alt and regulator.

I assume, of course, that red is actually blue/white.

*shrugs* i'm being over cautious, normally, but with my gt, i can definately defend the point, seeing how parts are rare at best.
 
#54 · (Edited)
maglinjosvinn said:
i'lm thumbing through the wires under the hood and i've realized something.

i have no blue/white stripe wire.

so.

coming from the 'bundle' of wires going towards the regulator and coil and what not:

red - stud on back of alternator. Should have a fusable link and go to one of the 4 studs in the fuse panel
green - coil/distributor Should go the the tach
clear - coil (oppoisite side of green) Should go to fuse #5
black (no color) goes to same post as said clear wire. Should go to the starter solenoid vertical male terminal

red wire to 3 wire pigtail that connects the alt and regulator. That should be a fusable link and the Blue/White wire connects to it

I assume, of course, that red is actually blue/white.

*shrugs* i'm being over cautious, normally, but with my gt, i can definately defend the point, seeing how parts are rare at best.
Look for the Blue/White wire to come from the inside the vinyl covering of the instrument panel harness, it should have a male/female spade lug terminal connecting the two wires together. HTH.
 
#140 · (Edited)
I'm a bit confused on this. I have one red wire from the harness going into the regulator plug. Is this the one that is part of the blue/white ammeter light wire? I'm putting in the DL 1345-6-7 so the wiring in post #70 is perfect for me, only what's this red wire?
There's the one for the output on the alternator too of course, and the old alt had a ground going to the lower bracket, I'm putting that back on. Need to get a pigtail for it yet but I thought I just had to do this blue/white (that I can't find) and the exciting wire. Hmmmmm
 

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#55 ·
ok. alternator is hanging off the spare engine. i took a random alternator arm out to my forge, bang bang bang, goes in, ground down the bracets, and away she goes. i gotta fille the groove in the adjustment arm towards the block cause the belt is WAY TOO TIGHT! lol. aside from that, golden

over all:

47 bucks. alternator and pigtail.



are two photos i've reworked. more to come. the first doesn't include the arm i fabed up, but i'll get a shot of it soon.
 
#56 ·
right then.

doesn't work.


mechanically, its sound. nice and clean. the problem?

i dunno.

it WAS putting out a 17 volt signal to my voltimeter at the stud on the alternator

but that was the only place. fusible link? i think so. so i tested it at the fusebox. 0 volts. well shisa, thats not good. hows the car running? i dunno. so i go back out to the alternator, test the stud again and 12 volts. odd.

the little red dash light is on. continually. when i FIRST put the alternator in, the red light would come on till you started the car, then it would either go out or dim. now it won't go off.

... gah. i'm stuck. its pitch black outside and as much as i hate going to bed with a problem, i got no choice.
 
#57 ·
You are really close to the solution. From what I have read (I think in this thread, but since I hit reply I can't go find it) there is one more wire to hook up. It is a white one (maybe?) that needs to go to the light on the ammetter that turns on the alternator. Without that draw of the light to kickstart it, nothing happens.

Search more here or for another similar thread on alternator wiring for the new single wire alternators. There is another plug that needs to be used.

I hope this helps.
 
#59 ·
*nods* i bought the alternator brand new, but i am going to take it to be tested today.

the white wire IS connected. i'm going to be going under the dash to check all the connection points.

PROLY - going to have to take down the fuse block, clean EVERYTHING and put it all back to gether. go me. i'm considering replacing all the wiring going 'under the hood' from the fuseblock at this point in time, and adding my underhood GEO 91 storm fuseblock so i can bring the headlight fuse out front, the fuse for the alternator output, the fuse off the battery... everything. really handy peice of equipment.

I did i confess, lay a screw driver by accident accross something when i was ... what was i doing. lol. nice big spark. the alternator still put 17 volts out after that, and the idiot light did go out. *sigh*

i gotta go to work in 30 minutes, then back around 4 tonite, at which point i'll have a few hours. *has to be to work again at 5 am the next day. hopefully i can find a solution.
 
#60 ·
well it worked. works. going on a road trip. i'll edit this post after work tomorrow to show you guys the solution.

in short. i bypassed the blue/white stripe wire. on the diagrams i saw for other cars w/ this alternator in em the white wire was supposed to be constant hot. period. the red wire. constant hot. period. so. i ran a relay from the key on fuses under the hood, and hooked a line up direct from teh battery so the alternator kenw the charge on teh battery. that point in time, the alternator either was putting out 0 or 63 amps of power. when i hooked it up that way, a nice 20 amps, which slowly went down to 0 or so as it charged.

thats it in a nutshell.

*lights are INCREDIBLE NOW!* lol. still putting cibie Zs in tho.
 
#61 ·
spdkilz02 said:
go to Guyopels photo album, he has a comparision of what the stock opel alternator and the gm 105 amp alternator look like together...the 105 is actually smaller then stock in size...
I asked Guyopel about the alternator and here is his reply.
Quote: The alt. # DLG 1345-6-7 from Autozone this is for a 91-95 Chevy pickup ( C/K bodystyle ) 350 cu.in. V/8 with A/C . You will need to use the Opel pulley ,the drive belt # is for a Dayco # 15355, the lower alt. bracket is for a Chevy. Pepboys # 42273, it is chrome and come with bolts . You will need to change to shorter bolts to mount the bracket to the Opel block . You will need to grind one slot in the bracket ( see photos ) and use spacers to move the alt. all the way to the frontof the Chevy bracket .You will use the Opel top bracket for adjustments . Hope this helps: End Quote

I looked at one at Advance Auto briefly the other day, and the adjusting bolt hole is clocked at the 2 oclock position and the bottom at 5 oclock. The present pulley is a serpentine. It was a little expensive, but definitely smaller. HTH, Jarrell
 
#62 ·
i hate to dig up old posts...

but.

i blew out my alternator last night, and replaced it today. i WAS bypassing the lamp in the amp gauge, perfering to put a relay and a 12volt current directly to the white wire. this solultion worked all last year and most of this.

now i've put in my engine, the rebuilt one, and i've popped two alternators in 2 days. not good. lol.

so. i decided to go back to the whitewire connected to the trouble light's BLue w/ white wire. Works like a champ, till you rev it up, at which point the AMMETER reads out 30+ amps, (its topsiding the guage, so i know its burning it up).

before you say 'disconnect the ammeter', i need to know WHY its putting out THAT much juice. i thought the alternator would regulate, keeping the amps down until the system demanded them, at which point it would pile them on until everything got what it needed. Currently, i can only imagine that the amps going through the system are 1, burning out my ammeter guage, 2, burning out every other thing in the car.

Prior to this modification, lets say, the battery was run low, like i was listening to my stereo with the car off. the ammeter, when you started, would read 10 over 0, and slowly drop down as the battery charged, until it reached zero. Other things, like turning on the turnsignals, or the headlights, would make the ammeter guage visibly drop below zero, but it'd eventually balance back off. This of course was with my other 7127 alternator, with the white wire just being fed through a relay direct from the battery.


Oh. the lite in the dash does in fact go out, as soon as the car is running under its own power. its just putting out way too much juice.
 
#63 ·
FINALLY!

battery was toast. was drawing max amps, and nevr charging. alternator was working like a dog to keep up. problem almost fixed. about to go spend more of my 'owe it back to dad' money.
 
#64 ·
O.K. I know this is an old thread but I have a question. I went to the parts house and looked up the 105 amp alternator for the early 90's truck and it has a 4 wire plug. I know the thread talked about the two wire plug on the 2167 alternator but I would like to run the 105 amp; not because of the extra amperage but for the size. So what's up with the plug? Any help would be greatly appreciated. :yup:
 
#65 ·
To be honest with you, I didn't examine the plug when I looked at the alternator. Pm Guyopel and ask him how he handled it, and ask if he will post his answer. I'm hopeful I can do the upgrade, by the end of the summer and inquiring minds would like to know. :yup: Jarrell
 
#66 ·
The Autozone DLG1345-6-7 alternator is a one wire 105 amp unit. I have been considering buying it, but have not as yet. I do have the 63 amp one that I got from Rock Auto, but I had to make a special bracket for the adjuster, as described in earlier posts in this thread. Both require the universal Chevy SB chrome bracket for the bottom pivot/mounting.
 
#67 · (Edited)
I just checked out the alternator plug on Willit? that also has a 4-pin plug, the harness I got with the 95 Camaro engine only has one wire going to the plug. It is in the center pin of the smaller holes. I hooked it up to the Blue/White wire going to the ammeter lite. Hopefully when I get the engine running, I'll be able to see if it is the correct hook-up. According to the Camaro/Firebird schematics, that one wire goes to the instrument panel, turns on the "check gages" lite and is the generator sensing wire. HTH.
 
#68 ·
Maybe ordering the plug for a 95 Camaro is the answer. I checked on the plug for the 92 Chevy truck CS105 alternator and though the alternator has 4 pins the connector only has three wires coming out of it. the question would still remain about the wiring with this plug. PM'd Guyopel but no response as of yet. I will also be checking with a very reputable alternator shop today. May be they can provide the answers.
 
#70 · (Edited)
sigh

There are 4-pins on that plug, though they all aren't required to be used and some regulators don't use all the functions anyway even if you did use them. The plug is available at any parts store these days, though usually it only comes with 3 wires. They are labeled most correctly by a letter designation, though generally the colors are pretty consistant.

If you look at the end of the plug it looks kind of like a capital "P." The wires should be as follows top to bottom in that configuration, but again labels are most correct:

-S- wire, this is the voltage sensing wire, and wherever you connect this one is where it will be sensing system voltage and adjusting to maintain it at the proper voltage. I'd recommend hooking it to the same terminal on the fuse box the resister wire for the coil is attached to, but that's just me. It should be a switched on source, on with the ignition. There are a few applications that don't use this one, but it is wired internally and can be added.

-F- wire, this wire is an output from the alternator to tell the computer how hard it is working to maintain voltage, because in some GM cars the computer would then run the motor up to fast idle to compensate. You won't be using this wire, and most voltage regulators inside the alternators don't have it wired internally either.

-L- wire, this is for the "idiot" light, and in a GT would be the one you would connect the blue and white wire to. In some applicatons this isn't used, because the computer would trip the light for you, but it's almost always connected internally if you wanted to run a light anyway.

-P- wire, this is a cool one. it is a pulsed square wave output from the alternator designed to be used as a tachometer signal on diesels. With some inginuity you could use it for the same, or you could maybe use it as a speed input to your cruise control, or maybe you just won't use it. Probably 75% or so I have come across have had it wired internally.

And lastly, there's the big lug on the back for the output wire, and you should probably run a ground wire too.

Remember, these are the new style modular plugs too, which means you can disassemble them and add/remove/move the pins around if the wires coming out don't meet your needs. If you only need the two wires, you can take the third pin right out of the plug like it never existed.

Hope that helps, have fun.
 
#71 ·
Hi , I can give you the info. Your connector should have four letters on the connector "S" ( Heavy gauge wire )
"F" ( Not used ) "L" ( This is connected to the Opel dash warning light wire that is on the org. harness that goes to the old voltage regulator ) "P" is not used. The "S" wire is connected to the battery terminal on the Alt. If you have a connector with letters that are different E-mail me and I will try to help . You must use the Opel warning light wire ( This turns on the Alt. )With this Alt. you use Chevy. Alt. bracket ( Posted In earlier Photos )and spacers and you use the org. Opel top adjusting bracket ( with a spacer ) and the Org. Opel pulley and fan on the 105 Alt. I used a Dayco fan belt # 15355
Hope this helps .
John Lewis
 
#72 ·
Just looked up the one that I bought that went with the Delco 63 Amp Alt. that I bought from Rock Auto, their part number 215-35. The pigtail came from paceperformance.com, part number PW30706. I think this would also work with the 105 Amp. Single wire alt.
 
#73 ·
I do not think this would work as the 65 amps alt. has a two wire flat blade connector .I used a G.M. connector that has three wires .The 105 amp. connector is also available from other auto parts stores and will have from four to three wires in them . HTH
 
#75 ·
I have a 1973 GT that has had the alternator converted to the single wire Delco unit. Everything seems to have been functioning fine as far as charging goes.I have had the car about 2 months so I am picking away at whatever looks like it needs fixing up. So, with that in mind, I decided to add the 2 spade connector to the alternator since it wasnt previously added.As suggested in this thread, I connected the wires to the pigtail wires and plugged the connector into the alternator.The red indicator lamp on the ammeter was lit as soon as I plugged the connector to the 2 spade terminal and when I started the engine, the lamp went out as it should. What am I missing here?Thanks
 
#76 · (Edited)
Nothing would think. The red indicator is supposed to go out and stay out when the alternator is charging and the internal regulator is working. If the light does not go out,or comes on as you drive, it's not charging. My son found this out when the charge light stayed on, due to the wire breaking at the pigtail plug in. Don't ask me the rest of the conversation when I asked him if the light was on when he was driving. :banghead:
Jarrell
 
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