It doesn't put out 140 amps all the time (like a simple generator would), it only puts out what the system is drawing at that moment, up to its rated maximum. If you were winching or welding it would crank out everything it's capable of.
GM alternator hum...
- Thread starter Skillet
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It doesn't put out 140 amps all the time (like a simple generator would), it only puts out what the system is drawing at that moment, up to its rated maximum. If you were winching or welding it would crank out everything it's capable of.
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- #42
I did know that it does not constantly put out the 140 but, at high RPMs on the highway, etc... I figured it would kick up above 100 amps, at least, with lights on, etc.
Wondering if I should up the fuse from 100 to 150 or if that is a bad idea.
Skittet, I never noticed any comments regarding how long the engine conversion has been completed and/or how long the alternator may have been working in your vehicle before it went to poo-poo?? Any chance you just completed the conversion, and the alternator was bad from the get-go?? You have a CS-130 alternator and wiring should be as follows:
(1) 12V from positive battery post to "S" on your plug.
(2) 12V from ignition switch to "F" on your plug.
(3) 3V from charge light circuit to "L" on your plug.
(4) "P" on your plug not used.
(5) And of course large white 10 gauge wire to large post outside plug.
(1) 12V from positive battery post to "S" on your plug.
(2) 12V from ignition switch to "F" on your plug.
(3) 3V from charge light circuit to "L" on your plug.
(4) "P" on your plug not used.
(5) And of course large white 10 gauge wire to large post outside plug.
When talking about that amount of power it would be wise to have an engineered solution. Maybe someone at Painless tech support, or find a friendly EE.
For a trail rig I think a breaker would be a better deal than a fuse.
Sounds like he up graded to the cs144 I've never seen a cs130 stock that put out 140 amps
- Thread starter
- #46
I have only owned the vehicle for a month but the build is pretty young. I would venture a guess that the engine does not have 3,000 miles on it since rebuilt. You could have eaten off of the original alternator.
So, below is what I found on the Painless website.
On mine, the white "L" wire from the plug is connected to something but I have not been able to find out what since I don't have a "Charge" light on the dash.
The rest of the wires from the plug are cut.
Perhaps the fact that the "S" wire is not wired to the positive battery post on the alternaor is why it is getting hot?
I figured it was not hooked up because it would be on the same circuit as the coil...(see the disclaimer about that on the diagram)
I am confused about that.
From the + post on the alternater, one line goes to the "Maxi Fuse" which then continues to the starter, etc. One line runs into the cab, I would imagine to the amp meter.
Just add up the amperage requirements of all your lights and accessories, round it up some, and get a fuse that size. But if you're going to be running a winch you will want more than 150 amps for sure.
I'm no EE, but ones that I know tell me that a circuit breaker is a resistive device and will heat up and hinder current before they blow, again not a good idea if you're winching.
Ok, I didn't want to write a book, but I guess I'd better give you the whole story. First, if the wire connected to your "L" post has more than 3 volts, that will instantly burn out the alternator. Now lets talk about you hooking this thing up without an amp light on the dash since your vehicle did not come with an amp light on the dash. In that case, ignore the Painless instructions, they are incomplete, and do not apply to you anyway. Do as I instructed in my previous post, 12V from positive battery to your "S" on plug, 12V from ignition switch/source to your "F" on plug, do not use your "L" or "P" on plug. NOTE; the "L" on your plug only applies to using an amp light on the dash, and you never use the "F" and "L" on your plug---one or the other!!!
Now, the exception to all I've just written is, and I quote: If using a late model GM alternator on a late model Vortec engine, you must install an in-dash alternator lamp and wire the lamp into the alternator circuit as specified in the appropriate GM electrical manual that applies to your engine. The lamp acts as a resistor, and you could burn out the alternator if not wired properly.
Now, the exception to all I've just written is, and I quote: If using a late model GM alternator on a late model Vortec engine, you must install an in-dash alternator lamp and wire the lamp into the alternator circuit as specified in the appropriate GM electrical manual that applies to your engine. The lamp acts as a resistor, and you could burn out the alternator if not wired properly.
- Thread starter
- #49
Great information, thank you... I will change out the wiring.
Maybe why the original alternator took a dump on me?
One more question, what are the odds that I did damage to the new alternator by running it for a about 50 miles wired as I have it now and getting too warm?
2 things... The alternator came from Oriellys.. So free testing... 2nd you only need a 1/2 drive long socket wrench to relieve tension.. orrrrrrrrrr if you go to any oriellys they will test for free.. anddddddd if you go to oriellys u can rent/ and return within 48 hours the serpentine tensioner release set... DO NOT REMOVE TENSIONER unless it is bad..Just checked at work(ORIELLYS) that is a Lifetime alternator and rated at 105? Where did u get 140 rating?
P.S. make sure in your rewire that someone did not put a resister inline instead of dash light. Another trick I have seen is folks using diodes inline and causing heck later on for poor guy who buys it from them.
P.S. make sure in your rewire that someone did not put a resister inline instead of dash light. Another trick I have seen is folks using diodes inline and causing heck later on for poor guy who buys it from them.
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I had one that a guy installed near the distributor hidden in the harness. We knew the bloody distributor worked when we put it on test stand. put it back in vehicle. rev it up and nothing.. two times we did this. two times it tested great in another rig. It was a wilson one wire setup conversion alternator. the diode had basicly melted down and was shunted. this caused the electrical system to not excite alternator hence not working. but on test stand it was different wiring of course. We finally found it after carefully(NOT) peeling back electrical tape. PO had about 40miles of it in like five layers over harness..LOL removed and wired up the alternator with proper resister and 1/2 mile of electrical tape and it still runs strong..
Just to be clear
You can EITHER wire "L" to a light or resistor OR put 12v to "F" ?? Either of theses (but not both) options will result in the correct function of the alt without negative consequence.
Why is it that you "MUST" use the light option on a vortec engine? Hoe does anything "know" that combination exists? Does the ecm/pcm/bcm look at it somehow?
You can EITHER wire "L" to a light or resistor OR put 12v to "F" ?? Either of theses (but not both) options will result in the correct function of the alt without negative consequence.
Why is it that you "MUST" use the light option on a vortec engine? Hoe does anything "know" that combination exists? Does the ecm/pcm/bcm look at it somehow?
CS-130 Alt. Wiring???
You are using a newer CS-130 Alternator, you may have it wired improperly??
(a) For vehicles with a red charge or amp light (no amp gauge), turn ignition switch to the ON position. Find the wire that went to your original alternator that is showing 3 volts or less with the ignition switch in the ON position. WARNING- anything more than 3 volts will destroy your alternator instantly. Connect this wire to the L post of the CS-130 plug.
(b) For vehicles with an Amp gauge, find wire that routed from ignition switch (12 volts) to the original alternator or regulator. Connect this wire to the F post of the CS-130 plug. NOTE- use L or F post, one or the other, not both!!!
(c) All vehicles, route wire from the positive post of the battery to S post of the CS-130 plug.
(d) Post P of the CS-130 plug is normally not used.
Perhaps my previous post didn't explain it in this language???
You are using a newer CS-130 Alternator, you may have it wired improperly??
(a) For vehicles with a red charge or amp light (no amp gauge), turn ignition switch to the ON position. Find the wire that went to your original alternator that is showing 3 volts or less with the ignition switch in the ON position. WARNING- anything more than 3 volts will destroy your alternator instantly. Connect this wire to the L post of the CS-130 plug.
(b) For vehicles with an Amp gauge, find wire that routed from ignition switch (12 volts) to the original alternator or regulator. Connect this wire to the F post of the CS-130 plug. NOTE- use L or F post, one or the other, not both!!!
(c) All vehicles, route wire from the positive post of the battery to S post of the CS-130 plug.
(d) Post P of the CS-130 plug is normally not used.
Perhaps my previous post didn't explain it in this language???