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TR2/3/3A TR3- Who offers a good alternator kit + starter

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More opinion, I guess. Terminal 1 (on the left if you are looking from back to front with the terminals on top) gets the yellow wire from the dash light. Terminal 2 needs to 'see' battery voltage, so you can either just jumper it to the big output terminal, or run a separate wire to the hot terminal on the starter solenoid. Most people prefer the former solution, I prefer the latter as it will get the battery recharged quicker after starting in cold weather (which may be important if you take a lot of short trips in the winter, like driving only a few miles each way to work).

My preference is to tie the main alternator output into the existing harness at the same point where the generator was, meaning you remove the brown/blue and brown/white wires from terminals A and A1 of the old control box, and join them together along with the wire from the alternator. You can also attach any new high current accessories at this point.

The advantage of this method is that the dash ammeter will still indicate whether the battery is being charged or discharged. That is also a disadvantage, as I hate having the needle hit the peg every time I start the engine (and it would probably tear up the ammeter eventually). To avoid that problem, I made a shunt to mount on the back of the ammeter, so it read approx 30 amps when the real charging current was 60 amps.

The other, more popular approach is to tie the alternator in directly to the hot terminal on the starter solenoid. Then either just live with the ammeter always indicating discharge even when the battery is being charged; or convert to a voltmeter.

You can read more here
 
Randall,
Wow, thank you for taking the time to type all that out.... I followed the link you posted and now I have another question.

Its mentioned that the 7127-12 should be purchased . I had no idea about this so I looked at what they sold me and its a 7127-3 .

Does anybody know if the -3 works or should I really get a -12.

My adjusting ear is at the same angle as the -12 in the link its just my wire connector is facing at the 3oclock position. That does not seem to bother anything though.

Thanks again
 
The 7127-3 will work. I originally put one in my TR3, but felt that the position of the plug-in terminal would be better at the 12 o'clock position. You have several alternatives. The first and easiest is just to exchange the -3 for the -12. The second would be to re-clock the unit yourself. Basically you just have to unscrew the two halves and turn them. There are several ways to do that however. The easiest is to remove the pulley and fan, unscrew the four through bolts, and then lift the front drive end housing up the shaft of the rotor enough so you can reposition at the -12 o'clock position. when doing this, you want to make sure that the rotor stays down in the rear slip ring end housing, or the brushes will pop out of the brush holder...

Which, brings us to the other method of clocking the 10SI...

Remove the four screws holding the two halves together, and completely separate the making sure that the stator winding stays with the rear half. you will hear the brushes pop-out. The brushes should now be dangling from a white plastic thing called the brush holder. What you have to do is get a paper clip and straighten it out. That is what you will use to hold the brushes and springs in place when you reassemble everything. Put one spring into the lower cavity (as you're looking down into the alternator back) and the push the lower brush into the same cavity with the wire oriented so it slides along the slot in the brusholder. Hold it in with your finger and from the back of the alternator push the paper clip in through the access hole back there. You'll have to push the brush down enough to get the paper clip in front of the brush. Push the paper clip in only far enough to catch the middle section of the brush holder. Now insert the second spring and brush and push the paper clip through the last hole in the brush holder. You now have the brushes set and can easily re-assemble the alternator into the correct position.

When you have the alternator re-assembled, just pull the paper clip out, and you will hear the brushes pop against the rotor slip ring.

If you have trouble setting the brushes with the brush holder in the back, you can always take out the three screws holding it and the voltage regulator in. Since the diode trio is attached to one of the screws, just go ahead and remove the three nuts and take out the stator and trio. The only thing you have to watch is the insulators on the three screws that you take out when you remove the brush holder. IIRC, one of them is NON-INSULATED, so make a notation of where that one goes.

But, you should be able to set the brushes without removing everything.

Edit: Yes boys and girls, it is possible to re-clock the 10SI just by taking the four screws out holding the two halves together and lifting the slip ring end housing JUST ENOUGH to re-position WITHOUT losing the brushes, but it's such a fine line that I don't recommend it.
 
sail said:
hermanmaire said:
I bought the pulley that was suggested
Click to expand...

Bummer, I believe you ordered the A202 although it was the A203 that was suggested.

martx-5 said:
sail said:
This pulley may work:
Wide Pulley
Click to expand...
:iagree: That A203 pulley and nut will fill the bill. The bore and diameter are the right sizes.
Click to expand...
Click to expand...


Darn it, your right. I'm the one who made the link to the ebay page for the incorrect A202. I guess all my eyes saw was WIDE BELT PULLEY and I did not think check the dimensions giving.

Thank you for confirming the A203. I will go ahead and purchase that today.
 
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