Hot Rods Alternator, electrical question

I have that issue on the big case high output alternator on my dualie. Sometimes the belt will squeal when I first start the truck up after it sits for a while. It usually stops in a few seconds though.

The Big red wire should have power all the time. Battery power when the car is sitting static with the engine off and you should be able to read the charge voltage off it when the car is running with it hooked up. It still should have power when it is disconnected as it is hooked direct to the battery and isn't switched.

 

ClayMart.The belt is adjusted very tight.Thanks Bruce.

 

I had wondered if your belt maybe was too tight ?
I look forward to hearing what you have found too be the cause of your problem.

 

The belt should have some deflection in it. I think like 3/16"? It definitely should not be tight as a drum.

 

Did you check all the pulleys on the engine to make sure they are all free and clear

 

An alternator should not be run disconnected. They are not like the old generators, they can put out tremendous amounts of voltage and burn themselves out without a load.
What brand of belts are you running? I have a dislike for Gates belts and hoses. They squeal and the hoses rot quickly.

Dave

 

Speaking of v groove belts. A lot of confusion on the proper belt for any given vee pulley.
Belts are not designed to fit into the root or (bottom) of a pulley. They should be riding high on a pulley so the tension squeezes the belt at its angled cut.

 

You should have one wire that goes to battery constant . ( weather straight to the battery or off the main starter lug, then to the battery) the other wire is powered up via the ignition switch.

You should be able to “twist” the belt 90* with tension on it or slight deflection when pushing down with your finger.

What has changed since you did the water pump?

Are the pulleys bright and shiny? That’s no good, just like glazed rotors or drums it will cause slippage

Are the pulleys straight and in alignment?
I have seen rebuilt and cheap water pumps have the pulley mounting flange pushes in or out a bit and cause noise.because the belt is not running straight

Pull the belt off and see if it’s glazed, and if it is is it in the bottom, both or one shoulder of the belt?
That will tell you if it’s a pulley issue, glazed, bent, out of alignment etc.

As has been stated are you getting the right belt
You don’t want it sitting to high or low in the pulley.

Hope this helps!

 

I was always told, 1&1/2”, but probably varies depending on length of belt.

 

I am going back down to the shop today and try to work on the station wagons alternator today again. If I find out whats wrong I will post it Thanks. Bruce.

 

Now I think it might be the P.S. belt howling{I never replaced it but will now}Question I have 2 RED wires that look like they go to the alternator, 1 comes off the battery and I think the other 1 comes from the starter.I could of sworn there was a small brown wire I took off there, but i dont see it now.There is a small brown wire with a few more that plug in under the alternator. Does this look right to you all. I don't want to burn up the alternator. I Goggled it but it didn't help much. Any ideas? Thanks Bruce.

 

If it is the belt that is squealing then it may need tightening or if its an old belt it may need to be freshened up. You can buy belt dressing in a can to do that or we used to use a bar of soap pushed against the belt when it is running. I liked Ivory but dial is better if you want a good deodorant soap.

If the alternator itself is squealing then I would suspect that you have an electrical problem and that has been addressed already.

 

Try using a bar of soap on the belt or crayon, easy way to get rid of belt squeal without using tools.

Best if you can find a wiring diagram, but the battery wire and starter wire “ should” both go to the main lug on the back of the alternator

Then you have 2 spade connectors on top I don’t remember which is which, but one is constant power and one is ignition power

There “ should” be another post on the back of the alternator for a ground wire, if not you could add a ground to one of the mounting bolts.

That looks like a standard Chevy alt from the 80’s should be able to google a schematic I think it’s an SI or S1 alt.

Hope this helps

 

Beaner beat me to it with the soap !!

 

Maybe try hooking those loose red wires to the alternator stud? This came with my harness kit, but you should have a plug with 2 wires in it. Wire #15 in the sketch is probably those loose ones in your picture.

 

I think you can see the red and brown wires in the background and look plugged in.Bob is right the red wires both go on the stud on back.looks like the alternater is clocked wrong for this car easy to fix.then you will see the plug on top.

 

Well good news .It was the P.S. belt that was bad. It didn't look bad, but it was. So I replaced it and wired up the alternator and she is running quite now. Just need 4 new tires and she should be ready for the road. Thanks to you all.Bruce.

 

Thanks for the update, most of us learn a little more each time we read a thread like this one.

 

Good stuff

 

Thanks to you all for your help.I just made a rookie mistake.LOL.Bruce.