Alternator question

[dmjlambert]

You should add an oil pressure switch that will stop the fuel pump if you have no oil pressure because the engine stops running. If you are in a crash and the engine quits, the fuel pump also quits. It's a safety thing so you don't start and feed a fuel fire after a crash. There are a variety of places on the web that describe how to wire it, here's one: http://www.gtsparkplugs.com/electric...mp-wiring.html

A coolant temperature switch like VetteVet mentions can switch the fans on as needed.

[dave`12]

@Going shopping tomorrow.

Questions about the terminal block:

12v vs 120v does it matter?
where should I look, home depot, summit racing, etc.
how many terminals do you recommend. Just adding the fans.
what about corrosion? do they make ones with weather protection?

thanx

[dave`12]

@ dmjlambert: I like that idea. Once everything is up and running, I'm going to look into that as well. Thanx

[dmjlambert]

This is the terminal block I'm ordering for my headlight mod coming up in the near future. It is just like the one on the passenger fender for the battery. VetteVet posted a picture of one earlier in this thread.



I like it because those plastic ears will make it unlikely to have an accidental short. I'm going to put it on the driver fender or driver side of radiator support, since that is close to my alternator.
https://www.ebay.com/itm/Goodmark-GM...k/302213106271

It should be fine to stack 3 or 4 ring terminals on it to connect different things.

Also VetteVet has posted a picture on another thread that looked interesting



3 or 4 inches from my positive terminal I'm going to put a bolt and nut through the fender to act as a convenient ground terminal. I've seen other threads where people have done that to provide a nice clean connection for ground straps. Around the bolt hole the fender needs to be nice clean bare metal.

[dmjlambert]

I thought this was an interesting link that I bookmarked for junctions
https://www.carid.com/battery-cable-junction-blocks/

[dave`12]

Those are ok for a couple of wires, but i think it could get messy quick, here is what I'm looking at - a cover for the weather, and allows more connections. 10.00 at summitt. It says for 7 circuits, but I want them all connected, don't I?

https://www.summitracing.com/parts/pho-ph3276

[dave`12]

Here is the same junction on my truck, which leads to some questions:

The one with the yellow cap goes to the battery

Red on the right is power for the a/c fan. Should I send this to my new terminal block?

Black to the ammeter

The other red goes across the radiator, I'm assuming to the junction by the headlights.

Is this ok, I'm thinking I should move the fan power...

[dave`12]

Now, the blue and white from the alternator need to be spliced together? That is confusing, am I just looping the two terminals on the back of the alternator? If so, then why do I need a connector?

Since my 4 pin (bottom pic) that was at the external regulator is now unhooked, it seems as if I'm just looping the white and blue.

And the other 2 wires? Red to the terminal?

What do I do with the brown?

Sorry, but this part is messing me up.

[dmjlambert]

Regarding the Summit fuse block: That does look quite nice and I'll bet it would keep things very tidy. I think it holds blade type fuses. I have seen some of this sort of fuse block come with or have available a bus bar terminal strip that will connect together one whole side of the fuse block, and that is where you would connect the power going in. I can't tell if this one has that. Something like this.

I'm not sure if you could buy something like that separately.
If it does not come with one, it's not a big deal because you can just solder multiple terminals onto your input wire.

[dave`12]

This is my junction. All this to the terminal with the 2 powers for my fans, and the power for my a/c fan?

[dmjlambert]

I'll have to think about all that wiring. Perhaps VetteVet will have some more guidance in the meanwhile. You're going to have enough info to write a small book soon. Keep taking pictures of what you have. Good documentation. Can you take a clearer picture of the regulator connector? There is a brown wire there too, right?

Is your intention to rewire the alternator connections to remove unused or unnecessary wires out of the wiring harness and make it cleanly wired the way VetteVet shows here:

Or did you have in mind to use jumper connections or one of those store-bought jumper blocks at the old regulator position? What about at the alternator, do you intend to cut the old plug off and connect the new SI style plug onto the white and blue wires with one of these plugs that VetteVet showed us?

[dave`12]

Glad you brought that up, I had misread the 4 pin from the regulator. Here is a better pic. The one that looks black is actually brown.

Red - no problem - it will go to the terminal (as long as my ammeter will still work)

White and blue go to the alternator. So if I jump them, all I'm doing is hooking the 2 terminals together. So I'm confused there.

The last is brown. It leads into the interior of the car. Not sure what to do with that one.

And, yes, I'm thinking I can save 20.00 on the kit with just some connections. But I'm not sure what the one that vette and you posted pictures of, because, like I said, it seems like I'm just connecting the white and blue together?

[dmjlambert]

If you were using store-bought adapters such as one I gave the link to in post #2 of this thread, this would end up being your wiring:


You can follow the wires to see it is the same thing as this from VetteVet:


So get rid of the white and blue wires. Connect the red wire that was going to the regulator plug to the red wire on the 12SI plug instead. And connect the brown wire that was going to the regulator plug to the brown wire on the 12SI plug instead.



Run a 10 gauge red wire with a ring terminal from the alternator screw lug to your new terminal strip/fuse box. This is in addition to the 12 gauge red wire also connected to the alternator screw lug, that leads to your stock junction where the 5 wires are connected together. You can leave that stock junction alone, or if you really want you can connect those wires to your junction block, but then you may be adding fuses and the stock configuration doesn't have fuses...

Connect non-stock things you want to power such as your fans to one of the fused terminals on your terminal strip and plug in a 30 amp fuse.

Run a 10 gauge black wire with a ring terminal from the alternator ground lug to the same place your fans are grounded. That will give you a nice solid ground for your fans. This is in addition to the black wire that is also connected to the alternator ground lug.

One last thing, do you have a fusible link between the battery and the terminal block next to the battery? Or is it plain wire? You should have 6 to 9 inches of 16 gauge fusible link wire there. That fusible link protects the rest of the wiring in case you have a short somewhere, that fusible link wire will burn up before burning up some of your heavier gauge wires.

Do all this work with the negative lead of the battery disconnected, and when done and before you reconnect the negative lead, tap it to the battery post briefly and lightly to see if you get sparks, which would indicate a short. That is another VetteVet tip from over here: http://67-72chevytrucks.com/vboard/s...d.php?t=763054

That's my 2 cents.

Less accurate diagram from first version of this post, disregard. I am unable to delete this attachment.

[dmjlambert]

And 2 more cents, so you have a total of 4 cents worth of my advice now. :-)
I like this stuff. It is non-adhesive tape like the factory used. Lets you wrap up stuff nice and neat.
https://www.amazon.com/gp/product/B00823GUP6/

[dave`12]

ok, let me parrot this back, see if I got it:

I will cut the 4 wires that went into the external regulator.
The red wire will go to the alternator terminal 2 (12 gauge)
The brown wire will go the alternator terminal 1 (12 gauge)
I don’t need the other 2 wires and can cap them off.

The red wire (alt output) will stay with the junction.
Another red wire (10 gauge) added to alt output and will go to my terminal block.

I have 2 radiator fan powers wires that now go to the battery. Remove them and run 10 gauge wires with 30amp fuses to the terminal block. Ditto the A/C fan power.

Add another ground to the alternator (10 gauge). Run it to where my fans are grounded.
So I now have 2 ground and 2 output wires coming off the alternator.

Oh, and thanx to your post #34, I see that I actually need a terminal strip, not a block. Something like this, but with a cover.



Next post will address your other concerns.

[dave`12]

Fusible link issue:

I assume this is the terminal by the battery that you are talking about:

I have 4 wires.

the one on the left that looks black goes to a fuse then across the radiator and into the wires going into the cab. I think it's part of the ammeter?

The red one on the left goes across the radiator to the junction.

on the right, top one goes to the battery.

the right bottom one goes to my aftermarket a/c fan power.

So I don't see a fusible link. Thinking the top right red one is the one you say should have one? If so, I can add one. The wire looks pretty heavy - probably 10 gauge. So I should split this and add 6-9 inches of 16 gauge with a fusible link? This sounds like it would easily blow, but I will take your word on it.

One other thing, I'm getting the non-adhesive tape, was thinking that as I was unwinding the original today

At the risk of repeating myself,

THANK YOU!

[dmjlambert]

The red and brown wires that used to go to the regulator but will now go to the plug on the alternator do not need to be 12 gauge, they can be something smaller such as 16 gauge. The red one senses the voltage level at your main junction some feet from the alternator, and the brown one senses whether the ignition switch is on and in some trucks grounds a generator light on the dash. So those are not heavy current applications.

Regarding The wire looks pretty heavy - probably 10 gauge. So I should split this and add 6-9 inches of 16 gauge with a fusible link? This sounds like it would easily blow, but I will take your word on it. The fusible link wire is available in 16 gauge, which is 2 sizes smaller than the 12 gauge you have running to the alternator, and has a flame-proof insulation. It is supposed to burn up if you have a severe short somewhere, instead of allowing your truck wiring to burn up. It's a sacrificial wire that acts as a kind of fuse. It's available at any car parts store, and I've only seen it in grey color lately.

[dave`12]

thanx - the fusible link will go on the wire that goes from the junction above to the battery, correct?

[dmjlambert]

Yes, it is shown on the wiring diagram with a resistor symbol, although it is not a resistor nor a resistance wire. I guess they couldn't figure out a better symbol to use.



Here is what mine looks like. The smaller black wire coming from the positive terminal is attached to the grey fusible link wire, which then connects to the terminal block.

[dave`12]

Well, the alternator from the camero that you recommended fit perfect. So clock position, mounting, pulley, existing belt - all that looks perfect. Very happy on that front.

Got the 16 gauge resistance wire and will add it as you instructed.

[dave`12]

Here is a pic of the terminal strip I got.

I would like sent my new 10 gauge output from the alternator to one of the large posts. To the other large post, I would like to put the old 12 gauge output wire that goes to the junction. This way, I could avoid extra wiring and cutting up the junction.

Then the fans go to the screws in the middle.

Cool?

[vince1]

I used to get CS130's with the plug at the junkyard for about $30 but only if they looked fresh with good bearings and usually with an overhaul sticker. They sure do charge better at low RPM than the 10si's. A listing for an 89 Pontiac Safari is a CS130 that has the V pulley.

[VetteVet]

Originally Posted by dave`12

Here is a pic of the terminal strip I got.

I would like sent my new 10 gauge output from the alternator to one of the large posts. To the other large post, I would like to put the old 12 gauge output wire that goes to the junction. This way, I could avoid extra wiring and cutting up the junction.

Then the fans go to the screws in the middle.

Cool?

The strip in your picture looks like it will work well. Attaching the old connecter is something you will have to do, but!, You won't need the old alternator output wire since you've replaced it with a 10 gauge wire, so it's basically a dead wire now. The one from the battery is absolutely necessary since it's a charging wire for the battery and it's critical for the ammeter to work. It's size and length is programed into the specifications of the ammeter gauge.

The other red wire is the cab feed wire and you can use it to feed the firewall block. It's a 12 gauge wire which should be adequate for the fuse and instrument panel especially if you convert the headlight power from the headlight switch to to a couple of relays on the radiator support.

I would concur with DJLambert's idea about the oil pressure switch to shut down the engine, but is it necessary? If you are running an electrical fuel pump possibly, but the mechanical pump is going to stop fuel flow when the engine quits, and if you lose oil pressure your gauge will show that, and I assume you will be watching those. Modern vehicles use warning lights so they might benefit more than our old trucks JMO.

I like Vince1"s idea about the CS 130 or the 144 especially about getting the wiring plug. They are a bolt in for the SI 12 but try yours and if you decide to go to the CS it is easier than the conversion you have just done. In fact you can buy an adapter that will plug into the SI end and then will plug into the CS alternator and it has the extra resistor installed. I think they run about $25. The best part is that they were used on just about every Gm vehicle made since 1994.

[dmjlambert]

Originally Posted by vince1

I used to get CS130's with the plug at the junkyard for about $30 but only if they looked fresh with good bearings and usually with an overhaul sticker. They sure do charge better at low RPM than the 10si's. A listing for an 89 Pontiac Safari is a CS130 that has the V pulley.

This is interesting info. Changes everything for me. I've been thinking about how the Mad Electrical web page http://www.madelectrical.com/electri...elcoremy.shtml does a good job talking about 10SI and 12SI alternators, how to recognize them, and the APPLICATION DATA section is the most interesting. It's what to actually ask for in the parts store to get a 10SI or 12SI, because you can't get one by asking for a 10SI or 12SI.

I have not seen a similar web page for the CS alternators. The electrical FAQ does not (yet) have anything about the CS alternators regarding an application. So, if I want a CS130 or CS144, not from a junk yard but from an auto parts store, I flat out can't get one, because nobody has revealed a usable application, until just now when vince1 did. Prior to now, if I don't have experience at junk yards that have older model cars, and if I don't want to just order something from Amazon or eBay and not really know what I'm getting, I was just out of luck.

Thanks for the post vince1.

[dave`12]

Originally Posted by VetteVet

The strip in your picture looks like it will work well. Attaching the old connecter is something you will have to do, but!, You won't need the old alternator output wire since you've replaced it with a 10 gauge wire, so it's basically a dead wire now. The one from the battery is absolutely necessary since it's a charging wire for the battery and it's critical for the ammeter to work. It's size and length is programed into the specifications of the ammeter gauge.

The other red wire is the cab feed wire and you can use it to feed the firewall block. It's a 12 gauge wire which should be adequate for the fuse and instrument panel especially if you convert the headlight power from the headlight switch to to a couple of relays on the radiator support.

I'm confused a little. I have the new 10 guage wire going from the alternator output to the new terminal. But, I'm thinking that I have to get power to the existing junction (solder by factory) by the headlight. I was going to do this by taking the end of the old alternator output wire that I cut from the alternator, but is still hooked up to the old junction, and send it to the new terminal because that's where the vehicle gets it power from. Am I wrong here?