Hello Folks, I have an old Texas T alternator and unlike the new single wire version this one has 3 wires comprising of 2 spade terminals and a stud terminal. I also have a short yellow lead that would fit one of the spade terminals and measuring this it seems to have a diode in series. I assume the stud terminal is connection to the battery can anyone please advise what connections go the 2 spade terminals go to? Thanks in advance. John
Based on my experience with my 1968 Chevrolet,I believe the two spade terminals are to power the field(The rotating field is connected to these terminals with thru a set of brushes). What I don't remember is if the field is powered at all times or only when the ignition is on.
Field is powered when key on, also need regulator Dave in Bellingham, WA
No regulator needed. The SI alternators have a built in regulator.
Looking from the rear of the alternator, the two spade connections are numbered 1 & 2, left to right respectively.
#1 needs the diode and is connected to the battery post. (Note bar side)
#2 needs a jumper to the battery post.
I have an older one too. But only two wires .One goes to batt and one with diode goes to Gen connection on dash. Got instructions if you want.
Thanks chaps for the replies. Ken I think your diagram looks to be what I am looking for however on the alternator I have there are no markings for the offset spade terminals. The yellow wire with diode you see connected will go on either spade terminal. I am assuming this diode is simply for DC blocking to prevent battery from discharging when not running so to test it wont matter which terminal has the diode? Your thoughts would be appreciated. Thanks in advance John
All bets are off. That's a Hitachi not a Delco. Those were usually used with Lucas systems and the Hugo automobile. I'll have to see if I can find the pin out. It makes a HUGE difference where you attach the diode. Typically, one pin is the voltage sense and one pin is the idiot light/reg control.
The idiot light/reg control pin would get the diode.
Also, it's not known if Texas-T made internal mods to the alternator. George said his instruction only had two connections.
I have an early Texas T alternator, purchased from Ralph Reeder (pre Ben Hardeman) so it is really old. It is on a car so I don't have it to look at, but I do remember that it had at least (and maybe only) one stud connection on the back of the alternator for a BAT connection. It does have two male spade connectors in a recessed plastic connector box that a tiny regulator plugs into. Evidently this model, and I think it is a Hitachi, was used a lot on Misubishi cars and trucks, I was told by Ralph. The case is drilled with two small tapped holes for mounting a regular Model T voltage regulator (for looks, only) if desired, but it would be for looks only and serve no function. The regulator that plugs into the recessed plastic connector on the back of the alternator, has two female spade connectors that it plugs into the back of the alternator on. That regulator is not a special Reeder parts, so I would expect it to be available through any auto parts retailer. I don't remember any marking on it, but I imagine if you took the alternator to a parts supplier, using his computer or parts book, he should be able to find the right part for you. The regulator that plugs in measures about a quarter inch wide by three quarters inch long by a quarter inch high not including the spade receptacles on the part that plug into the back of the alternator.
After looking at your picture again, my unit seems to be the same model, so you need to find one of those plug in regulators. Plug it on the spades on back (it will only plug in one way so you can't reverse it) and attach your BAT wire and you're done. Very Simple. If you can't find the regulator part over there, I'll remove mine; take it to NAPA and try to get one for you. It shouldn't be much to send it to the UK since it is such a small and light part, but try over there, first, to save the postage. By the way, since this alternator was bought in the eighties, it speaks well of the durability of the unit. I think all were 12 volt, at least mine is, so see if there is any stamping on your unit to indicate the voltage, unless you already know it. It will almost certainly affect the regulator part that is needed.
Thanks again chaps for all the replies, very appreciated. This old alternator is new still in the box, the box is clearly marked 12 volt. I hear your thoughts on the plug in regulator and indeed this could be required but the alternator was supplied with a pre formed yellow lead with a spade terminal that fits either one on the back of the alternator and it has a diode heat shrunk in line (I have measured the lead and its defiantly a diode). The fact this lead came with it makes me think wiring may be like Kens diagram above. Puzzling
John, I'll try to get a photo of my alternator and the plug in part and post it, within the next week, if you're not in a big hurry. As I said, the plug in regulator (or diode) was sold to me by the man who was making and selling the conversion, Ralph Reeder.
OK Terry no rush, thanks
Try this, it may help: