Help! Cant find electrical drain.

[Arl37]

69 chevy c10 with new crate 350. Draws .29 at battery post. Disconnected every fuse and every unfused plug I could find (ignition,headlights, wipers, coulmn connecttion ect). Only if I remove two spade connector at top of alternator does drain disapear. New internal regulator alternator. If I put yellow wire on spad with the number 2 beside it and the blue wire to the spade marked p, the drain drops to .01. I thought this set up was backwards but the ammeter in the car still shows charging when running with this wiring. Did I have the wires switched or is it something else.

[biggestjohn]

I had a battery rep show me once that voltage can leak across the top of the battery, down the side of the case to ground if the top wasn't clean, ie dirty, or grease build up. It can also do it down the battery cables. Most of the batteries that have corrosion around the posts are leaking this way.

I doubt that this is your problem, but with out more info, and pictures its hard to say. I just thought that I would share this little tidbit.

I guess that it could be possible to have some kind of build up in the alternator, a little spray with electric contact cleaner should clean up something like that.

[VetteVet]

Which of these two alternators do you have?








the first one has a 2 and the second one has a P.

Where do the yellow and blue wires originate. Did someone wire around the external voltage regulator or do the wires come from the harness?

[mud.man.rj]

Sounds like you have the first pictured alt by 2 spades, looking at the alt from the BACK of the alt the spade on the left is an ignition term and the right is Battery power.

[Arl37]

I have the alternator in the first piucture
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[VetteVet]

Well that at least gives me more to go on. If you had answered the rest of my question below the pics it would have made it even easier.I suspect that you do have the yellow and blue wires crossed. To confirm this I will provide some more pictures to show how the conversion is supposed to go.

This is the conversion with the external voltage regulator wiring harness left in the circuit.

You simply jump the brown wire to the white wire( the yellow wire in your harness is probably white and has faded over time.), and then you jump the red wire and the blue wire. Then the white (yellow) goes to the no.1 spade on the alternator and the blue wire goes to the no,2 spade.

Then you can simply reconnect the large red wire to the back of the alternator or you can upgrade it to a 10 gauge or even 8 ga. if you are going to have a lot of amp draw on the system. If you are using the battery gauge in your dash cluster then you will have to connect the large red wire to the same place it was.


There is no P on this alternator. There is on the second alternator I posted so I had to clarify that you had the SI series alternator in the first picture.

Here is the jumpered conversion.



Here is the conversion with the old regulator, and harness out of the truck. You can see the large alternator red wire is run to the same junction as the original OEM harness but it is upgraded to 8 ga. in my truck since I have a 100 amp alternator.




If you notice the brown wires in each picture, they come from the firewall block. The first picture it goes to the external voltage regulator and is jumped to the white wire which goes to the SI alternator at terminal one. The red wire is jumped to the blue wire that goes to the SI alternator on terminal no.2.

In the second picture the brown wire comes from the firewall block and goes straight to the alternator no.1 and the small red wire goes to terminal 2 from the junction of the battery and alternator and the feed wire to the cab.
most of the conversion articles will tell you to run this small red wire over to the large red wire on the back of the alternator with a small jumper wire. While this will work it is not the most efficient way to do it because it does not take into account "voltage sensing " on the circuits downstream of the alternator. If anyone wants more info on this they can go to Mad Electric's website where they explain it very well....http://www.madelectrical.com/electri...esensing.shtml

Also if you look at picture 2 you can see the fuses in the wires for the Battery gauge and how the wires are routed.This has been discussed many, many, times in this forum where the battery gauges don't work. An alternative to the battery gauge is to install a voltmeter in it's place.

[Arl37]

Yep I had it wired wrong so the way I switched the wires from what I "thought" was correct fixed the problem. I had the colors all goofed up I just traced the wires from the brown and the blue and figured it out. Thanks for all your help. Your explanation should be under FAQ. Very clear and concise.

[biggestjohn]

Originally Posted by VetteVet

http://www.madelectrical.com/electri...esensing.shtml

Wow, great site!!! I spent about 3 hours absorbing input!!

Thanks!!!