Alternator help please

[Fred K-OR]

This question is about an alternator I aquired with an engine awhile back. I do not have any history on it and would like some help from someone that knows much more about these things than I do.

Questions are:

1. Is it a 6 volt alternator?
2. In looking at the end of the alternator opposite the pulley (see picture), I know the one connection that is at about 10 o'clock says Bat. But what is the one that is down at about 8 o'clock for?
3. On the "top" of the unit (see picture) it has two plug type things and it shows a "12" right below these plugs. What is this for?

Rather than ask so many questions here, is there somewhere I can go and look up how to install an alternator like this?

Thanks again for the help.

[ford1]

its a chevy 12v three wire internally regulated alt, the lug way down on the alt all by itself is a ground connection, the two spades on top of alt are for power, run a wire from #2 spade to the batt termal on alt, #1 spade goes to the ign switch hot wire and it is only hot when key is on, it is there to excite the built in regulator, basically it turns the alt off when key is off, you can also hook it to the idiot lite wire to put the light out when alt is charging, its only hot with key on, its a chevy 3 wire alt and the only one to use, the one wire causes to much trouble, some times it will stay excited when engine is stoped and discharge the batt over night, i use the 3 wire type becaus they are so easy to wire and install, its easy to make a mounting bracket for them, only need one mounting bolt and one adjusting arm and bolt to tighten it

[Fred K-OR]

Sounds like it is something I don't need for my stock A's. Like I mentioned I picked it up with an engine I acquired awhile back. Looks like I need to put it on the swap site and see who may want it.

Thanks for the information.

[Gary WA]

Les Andrews Model A Ford Mechanics Handbook Vol. 2 has this info!

[Kurt in NJ]

the way it has the bar from the + terminal to ground, and a modified - terminal I think it is a converted to 6V +ground modified chevy alternator and what goes into the regulator terminals 1&2 on the edge depends on how it was modified.

[Mike V. Florida]

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Originally Posted by Fred K-OR

This question is about an alternator I aquired with an engine awhile back. I do not have any history on it and would like some help from someone that knows much more about these things than I do.

Questions are:

1. Is it a 6 volt alternator?

Can't tell from looking at the outside, you need the part number of he regulator.

2. In looking at the end of the alternator opposite the pulley (see picture), I know the one connection that is at about 10 o'clock says Bat. But what is the one that is down at about 8 o'clock for?



3. On the "top" of the unit (see picture) it has two plug type things and it shows a "12" right below these plugs. What is this for?

One BAT, one field and one sensing. Actually the field wire goes to the "idiot light" and then to the 'RUN' position of the ignition switch. The sensing wire either goes to the 'BAT' side of the ignition switch or the 'RUN' side depending on the application. When the ignition is in the run position the sensing terminal is energized with battery voltage and the field terminal is energized with a current limited voltage through the lamp. When the alternator starts charging, the field voltage raises and the voltage differential across the lamp reduces and the lamp goes out. The charging voltage is 'sensed' through the sensing wire and the internal voltage regulator regulates the voltage to about 14 volts.

Rather than ask so many questions here, is there somewhere I can go and look up how to install an alternator like this?

Thanks again for the help.

Here are a couple of sites for the most popular models the 10 and 12SI I don't know what model yours is;

http://mightymo.org/Proj_OneWire.html

http://www.alternatorparts.com/10si-all-in-one.html - Scroll down for parts convert/repair your alt.

PS - This information comes to you from a "purist".

[jrelliott]

Please note that the #1 terminal of these type altenators connect to the igniotion switch hot wire on later cars. The ignition switch on a Model A if original wiring is used is between the coil and the points. If you make this connection with this altenator it will not work! If you plan on using terminals 1 and 2 on the altenator, you will have to put a diode between the #1 terminal and the hot side of the coil. You will also have to put a fuse on the vehicle as the connection on terminal #1 is for the field coils in the altenator and will draw current when the car is shut off. You must pull this fuse when you shut it off or your battery will run down. Have an instruction sheet about this modification if you would like more info. Send me an email [email protected]

[Fred K-OR]

Thank you all for the help. Especially Mike and Jrelliott. Being you can tell I know nothing about alternators, I think I will pass on trying to use this thing. But your help gave me some idea what I would have to do in using it. I think I will pass it on to someone that has more use of it than I do. I still have a good working generator that I think I will use in putting this engine in my coupe. If anyone has a use for it, let me know.