Old allis drain problem.

First off let me say hello to all, I am new here. I just recently started working on farm equipment for a co-worker of mine, I am very mechanically inclined, but don't have papers. He on the other hand, not so much haha.

I am having a problem with an old Allis tractor of his (cannot remember the model, sorry) that has stumped me. It is a diesel, no bucket, has a cab. It is a 3 wire alternator, not a delco or anything, it's the one specifically meant for that tractor, he says he special ordered it, cost him big $$

He came to me one day claiming that he could park the tractor overnight, come back in the morning and it is dead. It would start with a boost right off the bat, but not by itself. So I went out there with my multi-meter and test light, did some poking around. When I tested for parasitic draw, it was drawing about .60 MA with key shut off, way to much. Now, the big stud terminal for POS on the alternator, the small wire hooked off of that, to the far spade terminal just a few inches over, if you unhook that small wire, the drain stops.

Now, he tells me that a wire has burnt off, somewhere just under the "hood" so I take a look. There was about a 10 gauge wire, coming off the alternator, to a small brown plastic clip, with 3 connection points on it. Only one of which was being used, from there, a smaller 14 gauge wire, ran up to the ignition, as far as I could see. This plastic clip melted, and ever since, these problems have been occurring, according to him, this is when this all started.

Now, with the tractor running, and that wire unhooked as the clip is burnt off, it is charging at 17 volts, putting out 30 AMPS on the amp gauge on the dash. If we hook those 2 wires back up together, it charges at 14.8, and the amp gauge drops to 15 AMPS on the dash. Problem is, even with those 2 wires hooked back up like they used to be, it still drains at .60 MA with everything shut off. Also, if we leave those 2 hooked up, they become VERY hot, especially the smaller gauge one obviously. There is no light on the dash for voltage, just an amp gauge.

What is this and what am I doing wrong? I can't figure this out. Every night he has to unplug the wires from the 2 spade terminals to stop the drain, and then it starts just fine the next morning. If you leave them plugged in, it sucks the battery away.

I would really appreciate some help into this, I am stumped.

From your description of the alternator it sounds like a internal regulated Delco. Also from your description it sound as if the voltage regulator in the alternator is bad.

Kent

I didn't have a chance to look, but do these old Allis tractors have an external or internal regulator? I think it is a 1972 model year, if that helps any.

Alternator is only a year old. He only uses the tractor in the summer, and it sits all winter, when he parked it last year, it was all good, now this year, right off the bat, nothing but issues. I would guess a regulator judging by how high of voltage it is charging at, but then why does the voltage calm down when I hook those 2 wires back together?

it sounds like a 160 which is a French tractor with a Perkins diesel motor. THe alternator has an external voltage regulator. The big 10 gauge wire goes to a junction block. THE block also has a red wire to the starter solenoid (back to battery) and a red wire to the key switch (to power all gauges). It would appear the #10 wire to the junction block sends voltage to the red wire to the solenoid, and then to the battery + terminal to make the charge work. Any leakage on any red wire to ground would give the drain your talking about, and the small red wire would get hot. The regulator has 3 wires to it, green is FIeld, bronw-white is #2 terminal and black is #4- ground. I can see that in the manual, if you infact have a 160. The small manual i have has the drawing, but no description of what the junction block is doing. The block appears to have a couple red-white wires on it that come from the key and go th the air heater???
I would guess your voltage regulator has a problem.

here is a poor picture to get you started. i can send one you can blow up thru e-mail if needed. [email protected]

<a href="http://s436.photobucket.com/albums/qq86/steve-ill/?action=view&current=160wire002.jpg" target="_blank"> </a>

If you could please send me a blown up version I would be very grateful, already sent an e-mail to you.

I will get the exact year/model number tomorrow and get it to you ASAP. I really can't figure out why this thing drains. Is the regulator mounted just behind the engine block, right by the safety switch for the clutch pedal??