hay all i have a 81 fb rx7 I got it for 800.00 bucks wasnt running well...and soon as i bought it i knew it needed work. well started with doing the maintance like new spark plugs wires cap rotor. oil change.....after all that was out of the way the car ran great . but what was strange about the car was it would kill the altinator on a week to week basis??? this had me stumped cause i never had a car do that to me before?
here is what ive done so far: ive gone threw 7 altinators and 5 batteries i check every altinator before i buy it to make sure it is runs right when i buy it. and i check the connections when it links to the wiring on the back of the altinator and the connecters to see if there is rust or anything out of place.with no luck...

a friend of mine said that i might have a bad ground was considering that but i dont see any of my connections being bad. here is what gets me is how can a alt that reads good run for a week and then just die?vis versa then too does the battery die along with it cause the alt dies. my guess that something is overloading the altinator internal voltage regulator . but other then that the car is fine except the altnator issue.....

here is what im guessing might be causeing it:

bad grounds on the car or just the ground for the alt
ecu maybe is bad?
the wiring behind the altinator is bad?

 

bump

anyone have any input on my issue?

 

When you say "die" do you mean that when you bring the alt. back AND TEST it, the test bench confirms that the alt. is no good?

My guesses from experince are:

#1: you do have a bad ground///take of (unbolt) your ground in the engine bay and clean them with a wire brush. Also get a wire brush that is for cleaning holes and clean the bolt hole too.

#2: you may be making the alt. belt to tight which can kill one (found this out the hard way)

#3: as for the battery, do you have a digital volt ohm meter with an "amp" setting. If so take of the + battery terminal and put the DVOM in series to the + terminal and cable. You should have no reading there... however if you have a digital clock or digital stereo you will have a very small reading. If you have anything above .0X start pulling fuses until the reading drops... and then start trouble shooting that circute for shorts.

 

sounds like a bad ground, replace your "now" ground with a new one, and also ground to the frame somewhere. also like rotor vs. piston said clean your contact points, use sandpaper if paint is in the way. You can also wire directly from the alternator to the battery to ensure you have a proper positive connection. That way you know your alternator is charging your battery.

 

I think you have something bad in the wiring check between the batt and the alt I had that problem and replaced the wires and that fuse box I put a 2nd gen fuse box next to the batt.

 

If you think you got a broken wire thats grounding it self out use a ohm tester or digital multitester on the wire behind alt and the other side on the frame or to the negative terminal on your battery. I got a fluke degital multimeter, it lets me know whether there is resistance or not by making a sound, when I touch the leads together there is no resistance so its basically a short. I have found this very usefull for determineing which wire is most likely shorted to the frame or corroded so that there is a seperation in the wire itself.

 

Do the alternators you've been using have integrated voltage regulators?