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Discussion Starter · #1 ·
Ok I just got my car all reassembled after puting a new southbend clutch in and doing some tranny work the same night i get it finished the radiator breaks. So I replace the radiator once i get that done i start it up and pull the terminal off of the battery and the car dies. Witch indicates to me that the alternator is shot. This will be my third one in the year that i have owned the car. It will be under warentee but still. I would like to figure this out cause it is a real pain to change that thing all of the time.

This is what happend with the other ones.

1. I got the car and it was shot so i got the car for cheaper.
2. I washed the car and got some of the wireing wet in front
3. When my radiator broke all of the wires got soaked

Thank you for your help in advance.
 

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Figure what out? Need help with what? You keep soaking your alternators appearantly. Stop doing that.

How does disconnecting the battery indicate a bad alternator?

The car is idling, so it won't be regenerating power.
How do the spark plugs get power without the battery?
 

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Aftermarket alternators suck. bottom line. My car has 186k and the alternator has been replaced once, with a stocker from a junkyard.

First thing I would check is the connections to the alternator. Getting them wet can cause it to corrode and burn up the wire from the battery to the alternator.

If it's still charging though, don't worry about it stalling without the battery connected. Mine did that too, even when my alternator was good :shrug:
 

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Discussion Starter · #4 ·
Why my alternator keeps frying.

Because the alternator creates a charge and the alternator will the car with out the battery.

I will get a new one tomorrow.
 

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DO NOT DISCONNECT THE BATTERY WHILE THE CAR IS RUNNING. This is not an acceptable way to test an alternator. Your car's battery acts as a filter for the electrical system and disconnecting it can cause electircal pulses to damage the car's electronics. Any service manual will tell you this.

If you really want to test the alternator, you need to take the battery voltage at idle with a multimeter. It should be 13.5-14.7 volts. You can also do a load test on the alt to see how much current (amps) it will put out. Also make sure to fully charge the battery (with a battery charger) before installing a new alternator. When fully charged, the battery should be 12.6 volts (engine off).
 

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magik8 said:
DO NOT DISCONNECT THE BATTERY WHILE THE CAR IS RUNNING. This is not an acceptable way to test an alternator. Your car's battery acts as a filter for the electrical system and disconnecting it can cause electircal pulses to damage the car's electronics. Any service manual will tell you this.
True.
you can actually damage the alternator this way.
Besides the fact that these alternators does not charge at all without battery power on the B+ terminal.
 

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Discussion Starter · #7 ·
Thank you for your input i know that running the car with out the battery but i disconected it for maybe 5sec cause the car would die. But originally why i posted is to figure out what the problem is with these charging system is all of the new alternators have a note with them basically saying your charging system sucks. But i have kind of ignored it.
 

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If it is an aftermarket alternator then it sucks and not your charging system. Just as everyone else said, aftermarket ones suck. I was on my 3rd one in my Jeep Cherokee from a factory installed recon'd alt. The guy even told me he usually expects to see cars 3-4 times just to find a "good" recon'd alt. And that came from a mech. at the Jeep dealership. If/When mine goes in my 6 I will not buy an aftermarket one, I will simply go test some in a junkyard and find a good one. Since you already paid for your I'd either get my money back and go the junkyard route or just deal with it and maybe get a good one next time........or maybe not.
 
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I've had an aftermarket one in my six for two years without a problem, I just put an aftermarket one in my protege a month ago, no problems yet.

Avoid buying them from Schucks, always stick with NAPA, and get their lifetime warantee. I've never had a problem with that line of alternators.
 

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Well, the ones that suck around here come from Discount Auto Parts/Advance Auto Parts. Not sure which brand they are, but that is who sells them.
 

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New found Alternator

Well... I was saving this upgrade for myself but I must share my findings. If you want a 100 amp alternator get one from a 93-96 RX-7. I asked my local alternator rebuilder about a upgraded alt for my 626. The 93-96 alt is the only one that has the same plug on the back to work with rewiring it. Now they did say its not a direct fit but pretty close. They say you have to mod the pully and the widen the bottom mounting bracket but other wise it will work.

Now don't get all piss-off at me if you try it and its nonsense. I'm just sharing the info I got. I plan on trying the Rx-7 alternator myself but I'm not to that point in my rebuild yet.

good luck:D
 
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