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Replaced alternator, starter and battery...Still having charging/starting problems


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Yep...1984 turbo wagon less than 150k, AT.

 

I replaced the starter, alternator and battery in the car about 3 weeks ago and have had to charge the battery 2 times since. It will start fine for like 4-5 days, but my voltmeter will read lower everyday when I'm starting the car, until it won't start at all. Under normal driving the voltmeter reads fine, it's just when starting the volts will read lower each time it's started.

 

So...What should I be looking for? Worn, crappy battery/starter cables? OR.......????

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Check the wire from the alternator, make sure its not corroded. Check the voltage at the starter yet? That should tell you if the cable is bad.

 

Okay, I'll take a look at the alternator cable and check the voltage tomorrow morning.

 

Thanks for the quick reply turbone.

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factory battery terminals still??? if so, junk em. new battery cables never hurt anything.

 

check the alternator to make sure its not outputting AC voltage... was it new or remanufactured? just because you paid for it, doesn't mean its good...

 

if you replace the battery cables, you can use the old positive cable (sans the cheapo stamped copper terminal that is bolted onto the cable lug) as a nice, handy battery to chassis ground strap. score!!

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factory battery terminals still??? if so, junk em. new battery cables never hurt anything.

 

check the alternator to make sure its not outputting AC voltage... was it new or remanufactured? just because you paid for it, doesn't mean its good...

 

if you replace the battery cables, you can use the old positive cable (sans the cheapo stamped copper terminal that is bolted onto the cable lug) as a nice, handy battery to chassis ground strap. score!!

 

Yeah dude, they are the factory cables/terminals...That's probably where the problem is coming from.

 

It is a remanufactured alternator, so I will check the voltage in the morning.

 

Hmmmm...

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Bad diodes in the voltage regulator rectifier circuit can cause the system to short and drain the battery.

 

Check for continiuty between the positive and negative battery cables without the battery installed. You should have VERY high resistance as the only accesories that should be on are the clock and radio memory, and the ECU memory. Pull out fuses till you find the shorted circuit. Disconnect the alternator, etc till the reading goes to infinity. That's how I always track down battery drain issues.

 

GD

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In cold weather especially you should charge your new battery before installing or they can FUBAR on you, I think the charge on most batteries sold these days is an acculated charge from sitting after the acid is put in but they need a good charge just to make sure. I worked at the NAPA store years ago and we always charged batteries we sold if at all possible and told customers to do it before installation if we couldn't. Most comebacks of new batteries were due to not charged, especially in cold weather. Never did figure out how to tell a pissed off customer that he should have listened to his instructions.:slobber:

 

 

Yep...1984 turbo wagon less than 150k, AT.

 

I replaced the starter, alternator and battery in the car about 3 weeks ago and have had to charge the battery 2 times since. It will start fine for like 4-5 days, but my voltmeter will read lower everyday when I'm starting the car, until it won't start at all. Under normal driving the voltmeter reads fine, it's just when starting the volts will read lower each time it's started.

 

So...What should I be looking for? Worn, crappy battery/starter cables? OR.......????

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Same thing happened to me just a few weeks ago - lucky for me, I was an MT, so I could push-start it - about 50% of the time.

 

I would pull the alternator and have it tested, Even if it's new. It's freaky, but it happens that they're bad out of the box - especially if it's rebuilt. The guy at the parts shop (altough he's been wrong before) says when the reman things, they sometimes replace just what's wrong, and not complete rebuild. I was totally unaware of that (and like I said, he might be full of it). In my case, the new starter was (presumably) bad.

 

I had replaced the alternator, the starter, the battery terminals & both battery cables. I also got a test light and tested the lead to the starter from the key switch. Everything seemed ok, so I talked the guy into ordering another starter. When I switched it out (I have to say, I'm getting' pretty good at it - I can get the complete switch in like 15 minutes), I've had no problems since.

 

Doesn't sound like your problem is the starter - I'd go with the Alternator like some of the other folks say - that would explain the slow drain. And yes, even if you just replaced it. They do come bad out of the box.

 

It doesn't hurt to replace the wires, either. One was a 36" and one was a 42" if I remember. Clean the crap out of your terminal connectors also (esp if you have a side-terminal battery) - sometimes that does it. Whatever you do, disconnect the battery before you out a wrench near that alternator - it's a really tight fit in there, the those fusible links are expensive as Hell.

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When you check the voltage one good test is to check the voltage drop between the main alternator output lug and the positive battery connection. If connections are ok there should be less than 0.25 volts between the two points with a good load on the system.

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Thanks again, I'll be out in the garage after work trying to track down the problem. I'm pretty sure it's an issue with the cables, but I'm not ruling out the alternator POSSIBLY being bad. So my plan is to pull the alternator, have it tested and buy new battery cables why I'm there at the parts store.

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When you check the voltage see how much voltage you have between engine ground and the output lug of the alternator while the engine is running around 2,000 RPM, with the lights and the blower on high. You should see over 13.5 volts. If not then the alternator output isn't enough for some reason. Possibly due to some bad output diodes.

 

Along with checking the voltages be sure all the connections to the alternator are ok and the belt is tight enough.

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A simple resistance check between the battery terminals with the battery out of the car will tell you immediately if the battery or the car is at fualt for the drain. If the see a drain, then check for continuity between the output lug of the alternator, and ground. There shouldn't be ANY reading. Just went through this exact problem with a GM alt that a friend had on his EA81. Brand new from Autozone, and the rectifier diode(s) failed and caused the same gradual battery drain you are describing. A simple check as I mentioned above will tell you immediately. A lot of times these rebuilt alts are cheaply done.

 

There's no reason to beleive that new battery cables will solve it - even if they were bad it still wouldn't cause the battery to drain, you would just see problems with grounding, and with running the starter. If anything, bad cables would cause it NOT to drain.

 

GD

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When I switched it out (I have to say, I'm getting' pretty good at it - I can get the complete switch in like 15 minutes), I've had no problems since.

 

 

you know... because of your avatar, i always picture you working on your car in that tux..... often brings me a chuckle.

 

thanks.

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  • 2 weeks later...
  • 6 years later...
A simple resistance check between the battery terminals with the battery out of the car will tell you immediately if the battery or the car is at fualt for the drain. If the see a drain, then check for continuity between the output lug of the alternator, and ground. There shouldn't be ANY reading. Just went through this exact problem with a GM alt that a friend had on his EA81. Brand new from Autozone, and the rectifier diode(s) failed and caused the same gradual battery drain you are describing. A simple check as I mentioned above will tell you immediately. A lot of times these rebuilt alts are cheaply done.

 

There's no reason to beleive that new battery cables will solve it - even if they were bad it still wouldn't cause the battery to drain, you would just see problems with grounding, and with running the starter. If anything, bad cables would cause it NOT to drain.

 

GD

 

I don't think the battery cables would be the culprit in this situation either, I would however consider the lead from the alternator to the positive post of the battery, I had a loose connection and belive it caused my diodes to fry (or at least one of them.)

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