alternator wiring

[Schurkey]

Is that a schematic for a '95? Not what I expected, and very different from my '88. If that schematic is correct for your vehicle, then by all means route power to the battery just like they show.

I'm not "against" MSD except to recognize that their quality/durability/reliability was never what it should have been, and is substantially worse now that the corporation has been sold and re-sold; they're sourcing too much junk from China. Their "core" product--spark boxes--seem to have a higher failure rate now compared to thirty years ago. Thirty years ago, racers had to buy two of 'em, and a special switch-box so that when the first spark-box died, they could flip a switch from the driver's seat to engage the second one.

I had an MSD 6T on my '88 for awhile. Ran good, looked nice on the oscilloscope. One day I'm driving along, and the engine dies. I coast into a parking lot, re-do the wiring to eliminate the MSD and return to plain ol' HEI...started up and drove off. I could have sent the box back to MSD for repair, but I never bothered. I can't tell any difference in the way the '88 runs with or without the MSD.

 

[eran tomer]

This is from the 95 factory manual, but it doesn’t say if this is for the regular alternator or for the cs144.

 

[GoToGuy]

What did someone (?) have mounted that needed a " catastrophe awaiting to happen " bus bar installation? Home made scare me, bus bars. A manual battery iso switch? Are running a big amplifier system, snow plow, other high demand electrical? If not, well it could be better. Are you using the gas engine page, that looks like the diesel page? On my 95 k2500, large gauge from battery pos over radiator support to main fuse box stud left fender. Large gauge wire battery pos to starter solenoid stud. Smaller gauge with fuseable link Alternator pos stud to battery pos. Battery ground to engine intk manifold bolt and thermostat housing. Smaller ground wire, battery ground to right inner fender. Good luck.

 

[AuroraGirl]

I would connect it via the OEM routing--which appears to be alternator to firewall distribution block stud, then the next stud over has a cable that connects to the starter solenoid, which then connects to the battery.

This way, the alternator power is being delivered physically closer to the loads it's powering, instead of directly to the battery--which then powers the loads through the double-long harness going first to the starter solenoid and then from there to the firewall distribution block.

The way it is now, you're powering the battery directly, but the other loads are getting power only via the extra-long cable from battery to starter to firewall distribution.

good way to word it thank you

how would you connect the alternator to the battery?

I explained earlier how the park avenue did it. alternator to positive spot on a fuse block, then lugged over to the battery positive, which also was joined by a lead from the starter to the battery(location being important for these)

 

[eran tomer]

metergood way to word it thank you

I explained earlier how the park avenue did it. alternator to positive spot on a fuse block, then lugged over to the battery positive, which also was joined by a lead from the starter to the battery(location being important for these)

so you say to connect the alternator directly to the underhood fuse box on the left fender??? isn't it a bit radical?

On my 95 k2500, large gauge from battery pos over radiator support to main fuse box stud left fender. Large gauge wire battery pos to starter solenoid stud. Smaller gauge with fuseable link Alternator pos stud to battery pos. Battery ground to engine intk manifold bolt and thermostat housing. Smaller ground wire, battery ground to right inner fender. Good luck.

i got the wire over the radiator cowl to the fuse box but it's not so large gage- barely 7mm diameter with the isulation.

 

[AuroraGirl]

so you say to connect the alternator directly to the underhood fuse box on the left fender??? isn't it a bit radical?

i got the wire over the radiator cowl to the fuse box but it's not so large gage- barely 7mm diameter with the isulation.

no im saying that the "where would you run the wire other than to the battery" is an example where my car does just that.

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The red cable running to the center out of focus of the pic is the cable from the fusebox lug where the charge cable also is, to the battery. the cable off the battery going straight toward the front of the car is going to the starter.

 

[AuroraGirl]

so you say to connect the alternator directly to the underhood fuse box on the left fender??? isn't it a bit radical?

i got the wire over the radiator cowl to the fuse box but it's not so large gage- barely 7mm diameter with the isulation.

thats what, an 8, 6,4 gauge wire? I dont pay attention to the larger gauge wires but the charge cable on my car is 8 and it could potentially be a little bigger.. maybe 6.. (yours pictured) but your truck probably runs it farther than my car so it would need ot be larger.

 

[454cid]

On your alternator, the plug has 4 connections

One of them has a specific function called "sense"

run a wire from that pin and place it where you want your truck to read "14.5" volts.

Old Chevys (1960's) used the horn relay, my old Buicks seem to use the starter. I discovered this when researching swapping in a bit newer alternator into a Buick and noticed cabling was a lot different than my truck. I have not had a reason to look at the scematics for the truck, to know where that wire goes

Yes it’s a cs144, and the car has the #19.

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this one is what they made for the positive wires, i guess it's not the factory setup:

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this one is for the grounds:

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the car does have an underhood fuse block.

btw- a scanner is showing a charge of about 13.5 while a multimeter on the battery show about 14, what does it mean?

What on earth are those monstrosites for? Has this truck been outfitted for some special purpose? Ex-service truck of some sort? I would remove that mess.

 

[AuroraGirl]

Old Chevys (1960's) used the horn relay, my old Buicks seem to use the starter. I discovered this when researching swapping in a bit newer alternator into a Buick and noticed cabling was a lot different than my truck. I have not had a reason to look at the scematics for the truck, to know where that wire goes


What on earth are those monstrosites for? Has this truck been outfitted for some special purpose? Ex-service truck of some sort? I would remove that mess.

If you mean a cs130 or an ad230 kind of alternator, most GM stock applications do not use the wire for sense unless the battery is remotely placed, in my experience, or the cable itself is just really long from alternator to charge point.
For example my buick park avenue did not use the sense wire because it was a short run to the box and battery, but a buick lesabre of 2000-2005 does because its under the back seat.

 

[thegawd]

@AuroraGirl

with the 4 pin alternators, if it's not being controlled by a computer, like on my 1956 case tractor that was a 6 volt but is now converted to 12..... is that one sense terminal the only one that matters? I took off one of these and replaced it with the 2 pin plug type alternator and wired up an indicator light.

so I have this 4 pin plug alternator and dont quite know what I should do with it..... I have not looked anything up as I dont actually need it but I guess I would like to know how to make it work...

if I understand what your saying, then the sense wire should go to the starter solenoid as it's also used as a distribution post.

what are the other 3 wires for? an indicator light? no? computer crap? no?

hell I'd look it up if I really needed to know this but it sounds like you know this info off the top of your head, and that's awesome!

CHEERS! Aurora!