alternator question - which wire is exciter

In a standard three wire internally regulated alternator there is a terminal for the 12 volts out.

there also is a two prong connector on the side that has a yellow and a red wire coming out.

One of these wires is attached to the alternator light on the cluster and the other is a 12 volt exciter that gets the alternator going.

Which one is for the exciter? Is it the yellow or is it the red?

I'm replacing the generator with the alternator and I'm not sure how to connect it.

I've tried the yellow wire as exciter and red for dash light and the alt light does not come on when I turn on ignition without starting.

So - that is an error.

I've tried it with the red wire as exciter and the yellow for the dash light and alt light comes on and stays on after engine starts. Alternator is freshly rebuilt.

So - that is an error.

In order to trouble shoot this further, I need to know with no doubt which wire is which.

thanks

 

In that configuration, did you try revving the engine up briefly? That type of alt won't start charging (and the light won't go out) until the engine hits a certain RPM first.

Stan

 

Ditto on what Stan said.

Try these sites: http://www.oldengine.org/unfaq/10si.htm

http://www.autorewire.com/tech/charging/Delco10SInandd.html

http://www.film.queensu.ca/CJ3B/Alternator.html#Delco

 

thanks guys

 

Let us know if that did the trick. I assume there is some sort of centrefugal switch?

MM

 

Nope: It's an "electron" switch. When "push comes to shove" at a certain RPM the "push" wins out and convinces the Alt. to start "pushing".

Sort of simplistic, but you get the idea. R)

 

i jad the same problem befor ei went with a gm one wire, reving the engine did the trick for me

 

look on the back of alternator. the plug should be identified as terminal 1 and 2. Number 1 (probably your yellow) is the idiot light. It is necessary for for charging to start. This can also be "flashed" to positive to force things to get going! Number 2 (probably your red wire) is the "sense", it is connected to the battery directly. I hook it to the wire that heads to the battery. If your Delco 10si is in need of repair, the diode trio, regulator, etc is available for cheap.... Bonus if running one of the most common alternators ever made! -Hill

 

I have one question. if you are not using a light then you use a 10 ohm 10 watt restistor, right. I did not find a wiring diagram for wiring this in. Do you just hook it to the ing. switch? I could hook it to the ing. for my HEI ing?

Thanks for the help with this wiring issue, I know it has been covered many many times

Mike

 

I have used the resistor instead of light on a couple of conversions. It doesn't matter where in the wire you put the resistor. I put them closer to the alternator, solder it in line and cover with some heat sleeving that is held in place with some heat shrink on each end, and then put plastic loom over that. The resistor gets hot, hence the heat sleeving, you used to be able to get some cheap from JC Whitney. I usually run that wire in its own loom so the heat can't affect other wires.

 

thanks for the recomendation.