QuickVet

what i was doing over the last few days was triing to find the battery draw on my car. i found it to be the alternator. i had all the fuses out of the car and all of those wires that go to the fuse box. Now i have all the wires back in the car and all the fuses back in.
before i got the new alternator in had cranked the car over a little after putting it all back together. seemed like everything was ok. now that i have the alternator in, there is no cranking action but everything else works. so i disconnected everything and double checked it.

then i put the alternator wires back on and the battery wires back on and guess what. SMOKE FROM THE ALTERNATOR AND I DONT EVEN HAVE THE KEY IN THE CAR!!!!

what the heck did i do now? :confused: i hope this is not as bad as i think it is. what do you think is the problem?

should i try putting the old distributor back in the car and seeing if it works? any ideas to save me :confused:

QuickVet

does the alternator even affect the car starting :confused: mabey i have two problems. somebody please help

killain

OK, Look. Somewhere you have grounded out the alternator, so before you do anything else STOP! You may have only one small problem but if you keep jumping around trying to fix something that doesn't have a thing to do with your current problem your just going to make matteres worse.

Go and look over the alternator connections, somethings cross wired here. Next make sure the battery is charged and then with all things shut off and the key out of the ignition, touch the postive cable to the positive post. You should see just a tiny spark, Make sure there are no open circuits, including the doors, make sure they closed and the window open and then touch the pole, now if you have an open circuit, Or short, you should see a spark at the battery. disconnect the alernator and see if you have the spark again? If you have a light on or a switch open it will show up. If you have a short in the alternator, have it checked at a auto electric shop. Only after you have found this problem and fixed it, move on to another problem. The distrubtor has little to do with the alternator so don't even mess with it yet. OK? Make sure you understand what i just said and if you need more help email me.

Phlash

Your new alternator could easily be shorted. Take it back to where you purchased it and have them check it out. The bridge or diodes may be shorted to the case, or an insulating washer may have been left out during assembly. It might be a late Friday afternoon alternator. :jester

Phlash 72 BB Roadster

QuickVet

oopps sorry. the word distributor should say alternator.

anyway, here is what i did. i put the old alternator back in and the car seems fine. no smoke and the car will start fine. no fire, thank god. and all the power items in the car work.

so what could be wrong? i hooked up the new alternator the same way as the old one and they definiatly appear to be the same in every way. should i just hook up the new one again and hope for the best?

QuickVet

i wouldnt doubt that :rolleyes: but before i do that, any other ideas? :confused:

Techno

What do you mean, you took the wires off the fuse block?
There is one wire to the starter that if it isn't hooked up won't let the starter work but everything else will. On old cars this wire can corrode and make the battery seem weak, or just burn through and open. But having the alternator smoke? you have something wired wrong. I would guess at minimum your rectifiers are smoked. (ac to dc)cheap but a pain to change, and at worst so are the windings.(I think thats hard to do though).
But the important thing is you have at least 2 things wrong. I think you should go over what you took off an double and triple check it. Somethings are wired wierd, like the wiper motor. one positive and the rest are grounds-at least on my year. If you don't have a shop manual you can probably get one from the library, it will have the wiring diagram.

QuickVet

are you talking about the battery postive post or are you talking about touching the alternator wires to its post?

QuickVet

the reason i had everything off the fuse block (all the fuses and the 3 wires that run into it) is because i had the distributor unplugged and there was still a draw on the battery. then i started pulling fuses to see what made the draw go away. and nothing did except the fuse for the curtisy accessories. then when i put all the fuses back into the box and plugged the alternator back in, the draw was back! so i unplugged the alternator and finally the draw was completly gone. confusing i know. but i need to fix the alternator before i can see if there is anymore power losses from the battery.

Techno

What killain was saying was the battery wires. You can also put a volt meter in between or a 12 volt light for the same affect. The power from the + battery post goes to either the voltmeter or bulb then the meter or bulb to the battery wire itself.
The spark test he mentioned is an easy no tools way. If there is a large load then there is a large spark. I'm sure you've seen this when you hooked up the batter cables. There should be a small spark but with a load its a bigger spark.

I'm thinking you upgraded your alternator since your old one works. Even though it looks the same there could be a difference, or as already mentioned defective. Smoke came out of it so it s a pretty good bet that putting it back in is a waste of time. If you know how, check the diode pack, this is probably what smoked. Old alternators had an external voltage regulator that a newer version has internally, This might be the problem also if the alternator is larger. But the wiring should have been different.

While your old alternator is in a simple test is to hold a screw driver to the back, where the shaft would be. Do this with the engine off, it should be slightly magnetic. Start the engine and try it again, (dont' put your hand into the fan) If its good it will be highly magnetic, real sticky. If its the same as with the engine off then its shot.

On the drain a big culprit is usually the glove box light or door light, those kinds of switches. The light bulb method works well for this as you can push in on the switches and monitor the light. The light glows brighter the larger the load flowing through it. works with the fuse way too.

lars

It's not uncommon for a bad diode trio or bridge rectifier (or diodes on the earlier cars) to cause a current drain on the battery. Also, if you ever hook an alternator up backwards or short it out in some way, you will blow the diode trio out of it (or damage individual diodes in the early cars). Diodes, diode trios, and bridge rectifiers are available and servicable at a fair price, so if you've damaged the alternator, it can be easily fixed, and troubleshooting is very simple - don't spend $150 on a new/rebuilt unit. I'll be glad to send you my alternator rebuild paper if you need it, or I can fix your alternator for you if you send it out to me - it's so easy to do that I'll do it for cost of parts plus shipping.

QuickVet

thanks for the advice guys. im gonna go back to work on it on thursday. i returned the other alternator and i have another one ;) dont worry the parts guy is a buddy of mine, he doesnt care. i even told him what happend. i will let you know how i do.

QuickVet

ok i told you i was stupid. after doing a little homework i found that the wires that go into the top of the alternator were reversed. weird enough they were reversed on the old distributor and it seemed to work :smash: :crazy: :rolleyes:

anyway the car was running and it is not in flames :troll

:smash:
:troll
me!


cars seems to run good though. and guess what! the new radiator hose is not sucking in like the old one. mabey the new cap helped.

on to the next problems :smash: :rolleyes:

theandies

Lars,
Where do you get your parts? In the past few years I have looked for these parts at various parts houses with no luck. They say "you can't get those parts anymore". I have rebuild many GM alternators in the past and get pissed everytime I look for rectifiers etc. I guess the parts houses make more money off of selling new alternators.
John