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Denso alternator connection question

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Westfield_XI

Westfield_XI

Jedi Warrior
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My Denso alternator has one large terminal for the battery cable and two smaller lugs: one for the light and one for ? . I assume that there is a 12V power source and a wire to the dash light, but which is which? The connector looks like a Tee with two tabs, how do I tell them apart? I am thinking that the red dash light should be energised when the key goes on, and lose power as the engine starts and the alternator begins to make power, is this correct?
 
Problem is, there are a lot of alternators in the world and many are designed for applications that differ just a little from the others. Some alternators have an accessible field terminal, which may or may not be the ignition light connections, some have a sense terminal (so the system voltage can be sensed at some point other than the alternator itself), and so on. Generally, you need to identify the output, and the point where you connect the "ignition" idiot light, and USUALLY you can leave the rest unconnected.

So, it's really impossible to say, without actually knowing the specific unit.

The only way to deal with this is (1) research it and find out, or (2) use an alternator you know about. Of course, you might get lucky and find someone who just happens to have done (1) or (2) already, but unfortunately that's not me. Good luck--
 
Most jap alternators with the 2 spade tee terminals use 1 for a tickler circuit which we do not need on Spridgets and the other is for the ign light.
Usually the verticle leg of the tee is for the ign light.
You will not hurt anything if you get it wrong, just try it and if it does not work, use the other terminal. Also some alternators just do not work the ignition light. I have 2 that are that way. All mitsubitchi alternators work via the verticle leg of the tee. Mitsu made alts for many vehicles. I like the Ford Festiva, it is very small and works just fine.
 
Yeah, I think you've just shown that anything is possible.

I used the Bosch Ford Fiesta/Festiva alternator in my bugeye. Practically a drop-in replacement, and it's very well documented on-line. Makes a nice, neat installation and you can use the stock V belt.
 
I believe it is, I will check tomorrow morning. I spent the day setting up the chassis and re-plumbing the cooling system as well as setting up the carbs. I am beat and am planning on starting in again tomorrow morning. My next 1 day permit is for Monday so I plan on tearing it down again over the weekend to work on it. I will check out the terminals on mine and swap the wires if needed.
 
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