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popping alternators like candy

H

huntingman2706217

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Welp i installed my bosch glow plugs... then the glow plug relay/solenoid died all together... it already was wired to a toggle switch so i went basically with what was there already... i found were folks were wiring the ford starter solenoids in parallel but i didnt mind not having the relay side... so i swapped the toggle to a momentary switch and installed the starter solenoid in place...

All was well for about 20 miles... then the solenoid died... swapped it under warranty and then the same day the original alternator died... kinda given... it was literally 1982 alternator with 103k miles on it... so i bought a new one... 40 miles later it quit giving juice... disconnected the wire off the back and it was turning .5MV so figured it was the new Alt... not unheard of... replaced under warranty and now again 40 or some miles later dead...

Im afraid something is wired wrong or wont work properly and is burning up the voltage regulator in the alternator... i wont be able to keep swapping the thing under warranty before they catch on... so i want to verify i did everything correctly with you guys... took pics with my phone and am posting this first so i can easily find the thread with my phone and hopefully upload the pics...

Only thing im not real sure of is the plug on top of the alt... the black is furthest center with the red closest to passenger side... it can go both ways... not sure it matters... not sure if i got it right...

Only other thing i know to do now is upgrade to a bosch alt...

The plug on top im guessing is for the voltage regulator... whats the voltage suppose to be there when running?

Thanks again!
 
Looking at your alternator wiring, it looks like you need to install a resistor in the trigger wire for the alternator. Some regualtors do not like having direct battery positive to them, and can pop prematurely from it. I believe you need a 35 ohm resistor wired inline for the trigger side.
 
Something to remember always test parts before installing them. Especially alternators, starter and the sending unit that goes in the fuel tank. Also, use 2 wrenches when working with compression type fittings. One on the compression nut and one on the other side. I just learned that lesson again the other day. Bad thing was I learned it a couple months ago on the Mitsubishi diesel. Sometimes a guy just can't learn enough.

What are you getting for alternators and where are you getting them?

Many years ago, I went through 3 Autozone alternators before I asked for my money back. I had already bought an AcDelco and installed it.

Also have batteries load tested before you buy them. I went through 4 or 5 batteries the last time, before I found 2 that matched

I'm thinking you should have about 13.5 or 14 volts from the alternator
 
jrsavoie said:
Something to remember always test parts before installing them. Especially alternators, starter and the sending unit that goes in the fuel tank. Also, use 2 wrenches when working with compression type fittings. One on the compression nut and one on the other side. I just learned that lesson again the other day. Bad thing was I learned it a couple months ago on the Mitsubishi diesel. Sometimes a guy just can't learn enough.

What are you getting for alternators and where are you getting them?

Many years ago, I went through 3 Autozone alternators before I asked for my money back. I had already bought an AcDelco and installed it.

Also have batteries load tested before you buy them. I went through 4 or 5 batteries the last time, before I found 2 that matched

I'm thinking you should have about 13.5 or 14 volts from the alternator
Click to expand...

mid brand Advanced auto alternators... i dont use them often and dont even know the brand name but with a online promo and free store pickup i got it for like $40 so hard to beat... their bosch is like $80 so im thinking these may just be junk... but im worried my wiring isnt right...

I tested both alts when i installed them and both were sticking 14v out when i first put them in...
 
THEFERMANATOR said:
Looking at your alternator wiring, it looks like you need to install a resistor in the trigger wire for the alternator. Some regualtors do not like having direct battery positive to them, and can pop prematurely from it. I believe you need a 35 ohm resistor wired inline for the trigger side.
Click to expand...

Thats all factory stuff already there and good... shouldnt need anything like that
 
Does it have a charge indicator light inside the truck to tell you if the alternator is charging or not? If not then chances are good someb ody has messed with the wiring through the years as I have never seen a GM alternator wired up with 2 heavy wires going into the alternator plug. The voltage sense wire is normally a large wire, but the trigger wire is almost always a smaller gauge.
 
there is only one wire going to the back of the alternator... then a black and red running to a plug on the top... every alternator ive ever done is this way... it is all factory... just an old farm truck thats been in a barn... yes the Alt gauge is there and works fine... but i posted what i was getting with the volt meter at the alternator already...
 
I usually run 2 heavy wires - one to each battery. The stock alternator wires always seemed to overheat. So I double up on them.

There isn't something like that going on here is there> I concur on the 2 heavy wires like that.
 
Is your solenoid hot wire coming from the same side as the alternator charge wire? I wonder if the solenoid main power wire should have "a battery in between" it and the charge wire or signal wire???? The solenoid might draw volts down because of such high amp draw of glows. And if that is the case it might be popping diodes in the alternator like your positive cable is loose.

Something about which wire is on top of the other at the battery. I think the alternator wire needs to be under the solenoid wire and or on the second battery. The solenoid power wire might need to be tied to the other battery and the terminal should be on top of the connecting wire?????

Seems I have put a tach signal wire on out of order and had a screwy tach signal in a similar kind of situation???????
 
jrsavoie said:
I usually run 2 heavy wires - one to each battery. The stock alternator wires always seemed to overheat. So I double up on them.

There isn't something like that going on here is there> I concur on the 2 heavy wires like that.
Click to expand...

one heavy wire to each battery from the stud on the back of the alt?

I could run a second to the drivers battery where the solenoid draws from also?

schiker said:
Is your solenoid hot wire coming from the same side as the alternator charge wire? I wonder if the solenoid main power wire should have "a battery in between" it and the charge wire or signal wire???? The solenoid might draw volts down because of such high amp draw of glows. And if that is the case it might be popping diodes in the alternator like your positive cable is loose.

Something about which wire is on top of the other at the battery. I think the alternator wire needs to be under the solenoid wire and or on the second battery. The solenoid power wire might need to be tied to the other battery and the terminal should be on top of the connecting wire?????

Seems I have put a tach signal wire on out of order and had a screwy tach signal in a similar kind of situation???????
Click to expand...

This is possible i guess... the solenoid draws from the drivers side battery... the alternator feeds the passenger side battery... i have no idea which post is on top of the other on the passengers side however if the positive being loose can kill the diodes then maybe i got a crap connection here... its possible because i did take them off at some point when either the original alternator died... i was checking voltage at the alt and has back feed from the batteries...
 
I have had an alternator die from loose connection to + battery. A loose connection can cause the alternator to go max output as it thinks the battery is dead. I think if it jumps to max output and off repeatedly it overheats the diodes from the high surge amperage. Kinda sorta similar to starting and stopping an electric motor repeatedly. Its the initial current is higher than running amps and its not meant to sustain that kind of heat except for short durations occasionally.
 
Yes a loose connection can kill one. Loose wire to the starter on one of my rigs fried the starter and alternator. set that aside a minute...

The alternator wiring is the same as it always has been, and the alternator just happen to go out after the glow plug solenoid work...hmm
How cold is it where you are- do you need the glow plugs at the moment? If not disconnect them and watch what happens. If you need then maybe start then disconnect the wire just make sure it cannot short out. Of coarse it's possible the alt went out by coins dense, but as a general rule, when you make a change and then things start going wrong something is messed up. I heavily suspect something with your switch and solenoid wiring.
 
Are you holding glows on while keying on starter to crank? Might loose power to solenoid during cranking depending on where solenoid switching power comes from. Might cause the solenoid to drop out and/or maybe chatter in which case battery voltage sensed at alternator might seriously fluctuate??????? Again mimic loose + post.
 
I just recently swapped the toggle switch out so its very possible it may do that... however the switch is powered from the original blue wire going to the original relay..

I did mess with the battery cables when troubleshooting everything... disconnected batterys while running to test alt when i didnt have my meter... im guessing. Abad connection then... im going to ditch that side mount crap and buy the screw in stud replacement... when the batteries die again ill get a top mount and stronger cca then...

I do need the glow plugs cause i got a hard start already... i injectors are on the way i hope to fix that issue then... lol

She will get there!!
For now im gonna redo battery terminals and go to a bosch alt...

Thanks!!
 
Another thing that leads me to believe it could be simple as the battery terminals is last night when troubleshooting it i had 14v at first on the gauge... this is right after i had to jump it off... which was right after driving it 15 miles home... 5 minutes later i had 9 volts and all my lights were starting to go out... so last night it did kinda seem erratic... which would indicate a loose connection... we will see and i will post back
 
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