Alternater Issues, Can't seem to figure it out..... Options

[martinef1963]

Hey Gurus - just wanted to see if I can get some ideas on how to isolate a little apternator issues.

1st symptoms dead battery (bought new one, two to be exact) R&R.

Battery kept running down, so I put a voltage meter to test the battery/charging system. It was spiking all over the place - up to 19 volts.

Bought two voltage regulators and R&R the old one. Still have spiking problems, so

Removed the alternator that I just bought (Bosch) and had it tested @ the auto parts store - runs perfect - 14 volts.

Did I mention that my alterator wires are new - from Bowlsby.

Now I've put it back toegether - it's running as I type, but the idiot light is still on!! (IMG:http://www.914world.com/bbs2/html/emoticons/headbang.gif)

Does anyone have any ideas on what could be causing the battery from going dead, and the voltage spiking all over the place? It is an electrical gremlin, but I can't find that sucker.

i've attached a picture of my girl -

thanks

[Joe Bob]

Hmmm, wierd. I assume that you have checked for correct wiring connections? What was it doing before you started all this? Or was this a resurrection from a long sleep?

Also...how confident are you in the volt meter? Have you tested the output reading on another car?

[McMark]

Sometimes the studs on the back of the rebuilt alternators are too long and hit the back plate. Perhaps one is shorting out intermittently.

[martinef1963]

Manfred - that girl is sporting a serious rack - I love it. I will check the volt meter out with my other car, however, it doesn't take away from the fact that now I have an altenator idiot light on. It's still running as I type.

When I changed it I made sure to clip the washers to ensure that they don't ground out the altenator. I just put this puppy back together and hold on and I will see if the light is still on.

I'm back - it's still on and the car is still idling perfect.... I'm going to take her out for a quick spin and get back to the board to see if anyone else has any ideas.

thanks gents.

[Dave_Darling]

The "idiot light" is the way that the alternator "bootstraps" itself into a working state. You need it for the alternator to start working. I don't know if unplugging the alt while the engine is running and then plugging in the VR will keep the alt charging.

Martine--the light is on; what's the voltage at the battery terminals?

--DD

[MarkG]

REAL long shot here, but whenever I blew the fuse for the turnsignals (defectivd TS Switch in column) my Alt light would come on.....

Just for the heck of it, check fuse box.....

Bad diodes will cause the light to go on also even though you may be getting 14v to the battery.....

[martinef1963]

Okay - I made it back, but definitely have a problem. Went for about a 3 mile drive and stopped the car for about 15 minutes. The battery was dead. Let it sit for about 5 minutes and got it started, pulled up to my house and the car died - no juice.

I got the alternator checked, the cables are brand new. I will be plugging the wires directly to the voltage regulator and see what happens.

I will be back in a bit to post the newest events.

thanks to all.

[DipShit]

You may need to polorize the alternator to get it's juices flowing.

[martinef1963]

Okay - I'm back. Plugged the wires directly into the voltage regulator and put in a new battery and no light.

I think the relay board is the culprit. What do you guys think? I don't think it's the battery cause I wouldn't be getting the red light, right?

I got a steady 13 volts w/ current volt meter.

v/r,

[martinef1963]

almost forgot - can I run the wires directly to the voltage regulator for lengthy time w/ out causing other problems?

thanks,

[Joe Bob]

At rest a fully charged battery should be 12.5-12.8 volts.....at idle 13+, at 2500 rpms, 13.5 to 14 max.....

[Joe Bob]

BTW...you only need a relay board if you have FI....
BTW2..you will need to complete the charging circuit by running a new lead from the D+ on the alternator to the light in the dash or find where the old wire was AFTER the relay board and jumper to it.....

[Dave_Darling]

The light is completely removed from the circuit if you don't plug the alternator into the relay board. So not having the light on won't tell you squat. You need to measure the voltage at the battery posts themselves.

Very good point on the fuse; check fuse #8 or #9 (I never remember which one). Pull it out and check it over; the fuses can seem fine at first look but actually be popped.

--DD

[Mueller]

no relay board on my car, so I ran a wire from the D+ (red) on the alt. connector to the #2 pin (next to the big yellow wire) on the 14 pin connector

[martinef1963]

Okay - I checked the voltage reading on another battery I put in (gel type), replaced the voltage regulator on the relay board - the light came back, but I'm assuming from the previous thread that if the voltage regulator is not on the relay board it bypasses the idiot light.

Gents - I'm not to smart when it comes to electrical problems. I've bought two voltage regulators, two batteries, Bosch altenater, and new cables from Bowlsby

What the F could be my problem here? When I replaced the wires on the alternator I ensured that I cut the washers as instructed to ensure they don't short w/ the cover.

I'm a pro a R&Ring stuff on this thing, but I suck at troubleshooting - I don't understand what running another wire from the D+ to the #2 that is located with the #14????

I will look at the fuses, but I need more help on what exactly this D+ wire does and how do I do it. Also Darling Dave - the battery terminals are still spiking all over the place anywhere from 12 to 18, 19, back down/up, down, etc...

thanks,

[martinef1963]

PS - how do you polorize an altenator?

[Mueller]

how old are your battery cables? did you clean the posts of your new batteries?

[martinef1963]

Brand new cables - I like to R&R (taking out the old and swapping with new). Because of my lack of troubleshooting skilz - I just R&R.

My starter is new the positive cable is new, and while I was at it I replaced the negative cable. I also bought an Optima battery and that is the one currently residing in the engine bay.

Help guys... (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)

[Dave_Darling]

QUOTE (martinef1963 @ Jul 15 2005, 01:13 PM)

PS - how do you polorize an altenator?

You don't--not one of ours, at least. IIRC, you polarize a generator, like you'd find on a really old Bug or 356. You might need to polarize a "self-exciting" alternator as well, I'm not sure, but that does not apply to ours.

If the voltage is spiking all over the place including very high, the regulator is not regulating worth a damn. Either your new regulator(s) are bad, or the wiring to the alternator is bad, or the relay board is. It might be possible that there is something inside the new alt that is intermittently shorting as well.

Sometimes new parts fail as they are installed, or immediately upon first use. It would be a big chunk of bad luck to have it happen to two VRs in a row, but not completley unheard of. And I know Jeff is as careful as possible when he builds up his harnesses, but it is possible that something happened to it at some point.

I don't know how to narrow this down further, other than by parts swapping which gets rather expensive. You might be able to check the wiring harness to see if there is any kind of cross-connection between the wires... That's the only test I can think of off the top of my head.

--DD

[Mueller]

I just re-read your post....so basicly your battery is dying when the car is parked? As if you left a lights on to drain the battery?