Burning up alternators

[proxses]

I keep burning up alternaters. I've gone thru two already. What should i be looking at that could be killing them?
I just converted to a 130amp. The first one lasted about a week. This one has gone for about 3 months. They just stop charging.
I found the first one died from a problem with wiring. I checked the wires again, so what could i check?
Any ideas?

 

[gt90stang]

proxses,

I can think of several things to check.

1. Battery, could have plate flakes shorting out under one or more cells. There is an open area under each cell for flakes off the plates to collect and when they contact the plates they short out that cell.

2. Charging wires rubbed through the insulation and short out enough to draw too much current. This could also result in a dead battery.

3. Bad Luck, I always buy new alternators as I had a real bad run of three rebuilds that died.

Good Luck, Don

 

[HISSIN50]

have you bench tested the old ones to try and see what malfunctioned?

Don's info is spot on. when checking the voltage, make sure to remove the static charge. or a specific gravity tester works (for me anyhow). Don is smarter than i am - im not sure how a bad cell would kill an alternator - just keep it from charging decently (not doubting you one bit, Don - im impressed with your stuff).

what type of alternators are you using (brand, new, reman'd, etc)? good luck.

 

[jrichker]

Check all your grounds.

The main power ground is from engine block to battery: it is the power ground for the starter & alternator.

The secondary power ground is between the back of the intake manifold and the driver's side firewall. It is often missing or loose. It supplies ground for the A/C compressor clutch and other electrical accessories such as the gauges. Any car that has a 3G alternator needs a 4 gauge ground wire running from the block to the chassis ground where the battery pigtail ground connects.

 

[proxses]

Well, I checked all the wires again. No problems there.
I have been running 4 gauge grounds everywhere since I did the swap.
The alternators I have been killing are Palladium brand from Advanced Auto Parts.
So I have yet to find a reason why this one died, but they gave me another one. Since this is my daily driver, I need to fix it fast.
The other thing is, they tested the alternator. It put out about 11.5v.
I'm not sure what's killing them, but I have a new one in there. So now I don't have to panic finding the problem.

 

[gt90stang]

proxses,

Check your charging voltage. It should be about 13.8V with a fully charged battery and not too hot. If you charging voltage is low then the battery could have a dead or intermittent cell. This could kill the diodes in the alternator. If the voltage is high then maybe the battery is sulfated, then the alternator would have to drive everything directly rather than having the battery as a storage device. This really shouldn't hurt the diodes.

Good Luck, Don