Auto Leco's - Alternator question for you.

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pokolbinguy

The Pokolbin Brewhaus and Winery.
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Hi Guys and Gals,

I am hoping there may be a Auto Leco Brewer lurking on AHB tonight that may be able to help me out with a small issue we are having with the new Alternator on our tractor.

If so, here it goes;

we installed a new alternator in our tractor today and the replacement has an extra terminal compared to the original.

the issue is with the sensor cable and which of the terminals it should be connected to.
when connected to terminal A (see photo linked below) when the tractor is not running the dash battery indicator light comes on, including if the ignition is off.

NOTE – The diagram i have of the original alternator shows the terminal marked as "Sensor Terminal" and the "Indicator" terminal forms part of the min 3 pin plug so I am assuming this is the sensor cable.
if i disconnect the cable from this terminal (A) the light does not illuminate (or goes out). same if i connect it to the other terminal (B) or if I disconnect the main 3 pin plug.

My question is, am I using the wrong terminal or do I have an issue (e.g the surge protector diode shot?) that needs rectifying. While it seems simple to use the other terminal I don't really fancy having to continually deal with a flat battery if things aren't working the way they should be.

I can not find any markings on the new alternator to indicate which terminal the sensor wire should be connected to so I was hoping the photos in this link will help someone help me identify them.

http://imageshack.com/a/img577/9274/injz.jpg


The terminal marked A is the one we used and that causes the light to illuminate. Should I use B? or do I have an issue?
Cheers, Pok

ALSO – I just remembered, when the tractor is running terminal A has no voltage reading but B gives a reading, and at full revs gives 14V. If this helps.
 

Ducatiboy stu

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"A" should go directly to the + of battery.

"B" should be conected to the ign light via the ignition switch from the battery.

When the light is on it indicates that the alt is not charging. If it stays on ( when you turn the key off ) it means it is not being switched thru the ign switch. What happens is 12v from the battety via ign switch and light energises the alternator. The light goes out because when the alternator starts charging it feeds 12v back to the light, so you have 12v either side of the light..hence it goes out. Normally the alt wont charge without the feed from the the "ign" light. You will also notice that the ign light stays on until the alt reaches a certain speed. Once the light goes out, it wont matter what speed it is going to charge.
 

pokolbinguy

The Pokolbin Brewhaus and Winery.
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Thanks Stu,

Question

- "A" you say should be connected to the + of the battery. I do not have an extra cable to do connect to this? There is only the main 3 pin plug, which actually only has two connections/cables as part of it and then the other cable that I am wondering where it should be placed. You can see the main "3 pin plug" on the RHS of the photos with the brown cables.

- As for connecting to "B"...i'll go and connect it to there now and flick the ignition and see what happens....if I am reading this correctly the light should come on if the iginition is on but engine not running.\

EDIT - I went and connected the cable to "B", turn the ignition to on....light didn't come on.

EDIT #2 - if I have it correct (just putting it out there for sake of asking this question), and the light is staying on with the cable connected to "A" could it be faulty ignition switch?
 

Ducatiboy stu

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Mm....you only need 2 wires. The thick one straight to the battery. And the other to the ign light. Sorry but cant see pic properly on my phone. The ign light may work on both A & B. Just try it and see. As long as you dont short any terminals to ground/chassis you will be fine.
 

Ducatiboy stu

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Yeah..brown stays where it is....the conector can go on A or B.......whichever on works
 

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