Alternator Problems.

[92eclipse_gs]

Alright. So about a week ago I went to start my car and it wouldnt start. I tested my battery, it was good. So i decided to replace the alternator. It worked. The car ran fine for about a week. And tonight when i went to start it, it wouldn't start again. I tried jumping it and i could get the lights turned on, but it wouldnt start. I took the jumper cables off and i couldnt turn the lights on. I'm almost positive it has to be my alternator again. This may seem dumb, but is there anything else i could be missing? Any feedback would be appreciated. Thanks guys.

-Nick

 

[Silverstrocker]

does it turn over

 

[92eclipse_gs]

The key turns over and it sounds like its trying to start, but thats when its being jumped though. When i first tried to start it it didnt even sound like it was trying to start. If that makes sense at all.

 

[FastYZFR6]

Try letting it charge with a battery charger Or leave the jump car hooked up for a while to charge the battery for a bit. The car will run without an alt on just the battery. Did you get the battery light, low coolent and brake light on at all when the car ws running?

Later,
James

 

[Old Mitsu Tech]

Well, take a voltage test at the battery with everything off. It should be around 12.6 volts for a fully charged battery. If it's below 12.2 it's classified as "dead" It needs charged. Charge the battery with a battery charger. It's not good to run an alternator on a battery that's dead. It may not hurt 1 or 2 or even more times, however, it puts a very heavy load on the alternator.

If the alternator is working and the battery is charged, you should have 13.5-14.5 volts at the battery. Any less than 13 volts and I would classify the alternator as needing repaired if all other things are good. IE connections and such.

Just putting an alternator on a car does not mean it will run forever. That is what warranties are made for.

The alternator is internally regulated and if the belt is tight, and it's not charging assuming that the large cable has voltage on it. I would have to come to the conclusion that the alternator needs replaced.

One last thing. With every thing turned off. I mean everything. Pull one battery cable and hook a test light in series with the cable and post. If it lights up, you have a parasitic draw and that should be addressed. You can do preliminary tests by pulling fuses till the light goes out. Or using a voltmeter, anything less than 130 ma is ok. It used to be a lot lower, but now because of keep alive power and such, the threshold has been raised a little.

Good Luck

 

[92eclipse_gs]

I took a voltage test and my battery is reading 11.5 volts. So if what your saying is right, then my battery is "dead." I'm gonna go ahead and get a new battery and see what happens and I'll let you know how it goes. Thanks for all the help.

-Nick

 

[ChicksDigBoost]

If the battery reads 11.5 volts, it may be dead, but may not need to be replaced. Put it on a slow charge battery charger for about 20 hours then test the battery it should be around 12.5 volts. You can also check the voltage at the battery when cranking, if its below 9.8 volts its not going to start the car, if its low it can mean a couple of things like excessive mechanical resistance in the engine or resistance in the starter but in your case it would most likely mean the battery. You can just get a new battery and go from there, but a lot of batteries a disposed of way before there time. I also recomended doing the parasitic amperage draw test that was metioned above, if you have too much the battery is going to go dead again whether its the battery you have now or a new battery. good luck

 

[92eclipse_gs]

Ok so i dont think its the battery. I took it out and tested it and its reading 12.5 volts. So theres gotta be something thats draining voltage, but i dont know what it could be. With that parasitic test i hook up on lead to the negative side of the battery and where do i put the other lead?

 

[92eclipse_gs]

Disregard that last post. I figured it out. Ill let you guys know how it goes from here. Thanks for the help.

 

[92eclipse_gs]

Just to let you guys know i solved the problem. It was alot less complicated than I thought it'd be. I took out the starter and replaced it and now its running fine. At first i thought it wouldnt be the starter because of the fact i was getting no electricity. I thought i might of had something draining my battery somewhere in the charging system, but luckily it was just the starter. Thanks for all your guys' help.

-Nick