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Mike S.
Mike S., Classic Car Mechanic
Category: Classic Car
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Experience:  A.S.E. certified with 25+ years experience.
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Ford Fairlane 500: Im upgrading my alternator on my 1976 ford

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Im upgrading my alternator on my 1976 ford mustang from a 55A to 100A the old one and new one have different terminals on the back. The old one has:

and (+)

the new one has

and (S)

I have no idea what wire goes where now and the new one doesnt come with a wiring diagram

any ideas
please help

This page here covers that alternator, click here.

I'll be back with the wiring diagram.

I know this is an Australian made car but wikipedia says the Amercian made TLD is the closest to it. Does this still have the external regulator with the markings 1 A S F?

graphicFor the entire wiring diagram, click here.


This shows all the hookups.


Customer: replied 4 years ago.

I havent come across a voltage regulator yet but what i have found is that the wires for D+ and DF run to separate box where i would normally find a voltage regulator (up front by the grill and headlights) and they are the only wires feeding into it and the box is labeled D+ and DF.


If its any help the old alternator is motorcraft / (bosch label on the back)

9120 060 753

u-k1-14v 55A 20

76 DA-10300-LA

Ok, let me see if I can find that wiring diagram. Is that the original engine? Are you sure it's a voltage regulator and not the horn relay? Wait, I will let you know. BRB!

Ok, it has to be because this alternator on there now came with this engine and this engine isn't original. Do you know what it came out of?

Actually, once you get the voltage regulator, you should be able to hook it up by the diagram I gave you. Are the color of the wires the same as what was it that diagram that I colored in the wires?

Wait just a minute. I have been looking up fairlane and comparing it to an LTD, now I read you also said Mustang. Which is it?
Customer: replied 4 years ago.

pay no attention to mustang its a fairlane and your right the closest to a 76 fairlane is a LTD they stopped making Fairlanes in 1970 back home

Are the color of the wires the same as what was it that diagram that I colored in the wires?
Customer: replied 4 years ago.

no the wiring is different i got 2 yellows in the mix i think after 30 years theres been some chnages made by previous owners

Ok, do you have the voltage regulator yet? I am sure we can get that hooked up. It shows where the wires go, so it really don't matter about the color, we can run all new wires if we have to.
Customer: replied 4 years ago.

no i dont, i thought 4 wires to the old alternator, i could simply take those 4 wires and plug them up to the new alternator

Well, you obviously need the correct voltage regulator that goes with that alternator.
Customer: replied 4 years ago.

ok so it sounds like i now need to get a voltage regulator and wire it all up like new, any idea what voltage regulator to get then?


I suppose a Motorcraft.
Customer: replied 4 years ago.

ok should be able round one of those up, i have one off of my old car but that had a 55A alternator on it as well. Can i use that one or does it have to be a different one since i'll be using 100amp alternator now

Is it a motorcraft? Give me the part number off of it. It should work, I see autozone lists them for 35, 38, 40, 42, 55, 60, 61, 65, 70, 100 Amp. Motorcraft Equipped

If it's a VR730, it should work.
Customer: replied 4 years ago.

you know what at those prices i'm gonna save myself the headache of searching for it and just grab one new.

now once i have it and mounted, i simply wire it up like the diagram you provided?

the question i have is with the 1 prong coming off the voltage regulator. The ground wire connects to there and then the green/red wire also connects to it? and that green/red wire what does that connect to from there my Alt dashboard light?



Yes, for the idiot light.
Mike S. and 2 other Classic Car Specialists are ready to help you
Customer: replied 4 years ago.
Perfect thank you for your help
You are welcome and thank you!