806 alternator draining battery

I have a retro fit 10 SI alternator on my 806. I found the external regulator was still on the tractor with all the wires disconnected, so it shouldn't be affecting anything.

I had posted on the forum here on 12/15 about my alternator heating up, then not charging at all. Based on the information I got in responses I got things hooked up and my alternator was charging perfectly at 14 volts into a single 12 volt battery and not heating a bit. I really appreciated the help. But I still have problem that showed up after it sat a couple of days. The battery was pretty well drained.

The picture is how I hooked it up.I got a few extra ones in there of the same thing. That 10 gauge wire goes directly to the battery.

I do not have the diode in it yet. I have them ordered but wired in the idiot light for now.
The drain occurs when I hook up the sensing wire from the output post to the #2 spade of the internal voltage regulator. With that connected I get a full 13 volt discharge, checked between the neg post of the battery and ground. Taking that wire off the regulator spade stops the drain. The "exciter" wire isn't affecting anything.

I thought maybe the alternator was bad even with a new regulator, but it checks out fine at an auto parts store. I'm sure it's something I have crossed up, but don't know what it is. I can run the tractor like it is and just disconnect the ground strap, but getting it working would be better.

Appreciate the help, as always, Bob
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If you have the #1 wire on the 2 wire plug hooked up to the wrong place it will in fact cause the battery to be drained and also can/will burn the alternator out. You need it hook up to the ignition in such a way that with the ignition shut off it has no connection what so ever to the battery power
 
With no voltage to the #1 "excite" terminal the alternator shouldn't be drawing a significant amount of current through either the large output stud or the #2 "Voltage sense" wire.

Can you measure the actual current draw instead of the voltage differential?
 
Is the diode polarity correct? the band on the diode must be on the side pointing to the alternator. Another issue might be the old regulator and wiring connected to it. It should be removed and wires traced to assure they are not hot. Jim
 
Just the voltmeter is all I have to check with, Bob. It shows the 13 volts and turns a test light on.

With the switch off there isn't anything at the "excite spade" on the voltage regulator. Since the wire comes over from the battery feed that puts current into the voltage regulator at the #2 spade. I did a temp wiring going from the #2 spade to the wiring plug, leaving the connection to the # 1 spade open. That gives me drain. Disconnect that and connect the # 1 with the spade to harness plug open and there's no drain with the switch off.

The three posts are hooked up pretty much like in the picture, except I don't have the diode yet. I believe the idiot light was a substitute for that diode, which I was doing for now.
 
I don't have the diode yet, just the idiot light in the system. I ran the new wire to the load on the switch over to the idiot light, then to the excite spade. The only wire I used that was on the tractor was the 10 gauge going directly to the battery. I haven't got an ammeter. With just the 10 gauge wire hooked up and the wire going to the regulator from the output post where the 10 gauge is hooked up, there's no drain.
 
That's pretty well oriented by the harness plug, but there was some other wiring spices I took apart to be sure. The hot wire from the battery feed post goes directly to the number 2 spade on the volt reg. The other spade (#1) goes back to he idiot light and switch.

Thanks for the help.
 
Let me correct that last post of mine about the jumper wire going from the output post on the back of the battery. With that jumper connected to the voltage regulator is when I get the drain. If I disconnect that from the voltage regulator, the drain stops. That's with the wire to the battery hooked up to the alternator.
 
Sounds like you need to take the alternator into a parts tore and have it checked. I know you have had a number of problems with this and to me it sounds like some how you have managed to some how burn out something In the alternator because the #2 wire should have zero voltage draw when running or not running it is the sensing wire which tells the alternator V.R. what the battery is doing and if that is shorted it will drain the battery
 
That was what I started getting concerned about so I took it and had it checked. It checks out fine. The thing I'm wondering about though is the number two spade is showing continuity to ground. That would explain the battery drain, but how could it charge and pass the test at the auto parts store? Unless it would only show the charging and not a grounding of any type.

Has to be something there. I thought it must be a bad voltage regulator.

Thanks again, I'll keep working on it.
 
The smaller wire from the Bat terminal (big stud) to the Sense (#2 spade) should not have current flowing through it. It should just provide a voltage source to help control the output voltage. If the drain stops when that short wire is disconnected, the regulator has serious issues. Make sure it is connected to the #2 spade. The idiot light must not be grounded in any way. the excite current comes from the key switch, to one of the lamps terminals, the other lamp terminal must connect to the #1 Spade. This puts the idiot lamp "in the wire" from the key to the Alt. No ground to the lamp. When starting the tractor, the lamp will turn on because the regulator in the alternator acts like a ground (electronically) and the voltage from the key provides the volts to make it glow. When the alt turns and the tractor starts, the regulator #1 terminal stops being a ground, and becomes 12v. With 12v on both terminals of the lamp. and no ground, the lamp goes out. I hope this helps. Jim
 
I have found that many of the test machines in auto parts store only get it right 50% of the time when testing things. I have them do the test at least 5 times and even then sometimes take it to another store and have them check it also
 
That helps a lot, Jim. This voltage regulator is new, but it must have a circuit to ground it shouldn't have. I don't know why it passed the test as being good. It does charge OK. The problem is in the drain afterwards.

I see what I can do with it.

Thanks again for all the help. Really appreciate it. Bob
 
I am making an assumption that the original external regulator is not involved. New parts are sometimes non functional out of the box. Making electricity sometimes makes testing people believe it is OK. Jim
 
Pull the Delco alternators regulator plug off and look down between the regulator blades. If there is a little metal web connecting the #1 and #2 regulator blades, use a narrow hacksaw blade to cut out that web.

If no web at the alternator plug, remove the tractors old regulator cover down by your feet and unplug the regulator on the chance it is your battery drain.. Remove the regulator or not, but tape up the plug so it cant short to any metal.
 
I'd have to say I hope the original setup isn't involved. That wiring is still on the tractor but the charge wire to the battery is all that is in the circuits. The original regulator is completely disconnected but the wiring harness is still there with the lights, etc.

But this ole girl has had a lot of "just make it do's" before I got it. The lights, charging, and starter all worked. The rest of it I worked around. I take another look at this alternator, maybe change the regulator, if need be.

Really appreciate the help on this and all things in the past. You guys are the very best.

Thanks, Bob
 
Thanks Jon. There isn't anything like that on this one. I have all the old wires disconnected. I'm looking at the regulator for a ground fault now. I have two different alternators with two different bench readings on the grounded regulator spade. One shows # 1 and the other #2. I'll post back if I get a fix.

Thanks for the help, Bob
 
Keep your idiot lite, do not change to diode in your situation.

The #1 pin on alternator and power to ignition coil both feed from the switched side of the ignition switch. With the engine running and no isolation between alternator and switch, when the switch is turned off to shut down the engine, current can feed back from alternator #1 to switch to coil and allow the engine to continue run.

Some form of isolation is needed between alternator #1 and switch to prevent this engine run on. A diode, idiot lite, and resistor are all options to do this.

Since you do not have an ammeter, keep the idiot lite. It will give you a charge/no charge indication that you would lose with a diode and no ammeter.
 
?But I still have problem that showed up after it sat a couple of days. The battery was pretty well drained.?

?The drain occurs when I hook up the sensing wire from the output post to the #2 spade of the internal voltage regulator. With that connected I get a full 13 volt discharge, checked between the neg post of the battery and ground. Taking that wire off the regulator spade stops the drain. The "exciter" wire isn't affecting anything.?

I?m confused by your statement ?I get a full 13 volt discharge, checked between the neg post of the battery and ground.?
Are you meaning that with #2 pin connected to output stud you are seeing 13 volts between #2 and negative battery post as ground reference? If so that is normal.

Under normal conditions and the battery connected, the output stud on the alternator and the #2 should always show battery voltage, regardless if switch is on or off. The #1 should show zero volts with switch off and voltage with switch on. The voltage may vary depending on type of isolation device used. #1, #2, and output stud should all be at battery/charge voltage with engine running.

If it takes 2 days for battery to drain, it is a slow leakage. I have seen this happen with a couple of ?one wire? alternators, even if connected as a 3 wire. This slow leakage could be undetectable on an auto parts store alternator test.

If you do replace your alternator be sure and get a 3 wire, not a one wire. With the one wire you will lose the function of your indicator light, and, since you already have it set up as 3 wire, a one wire will not simplify anything.
 
Do you have an older 20-0-20 or 30-0-30 ammeter such
as were found on an M or H?
If so, connect a wire to each post of the meter. An
alligator clip on the other end is helpful.

Pull the #2 wire off of the regulator spade & hook up
the ammeter between that wire & the #2 terminal.
Read current draw on the meter, & report what the draw
is.
All of this with the engine off--not running.
Sounds like the regulator is shorted internally.
Jim
 
Another thing---remove the heavy short jumper wire from the alt.
output terminal, when testing.
Check with the ammeter between the heavy batt. wire & #2 spade.
Also test between heavy wire & output post on alt.

This will show if a short in the regulator or in the rectifier bank.
Jim
 
Sorry about the confusion from my description. The 13 volt drain was the voltage I get between the negative post of the battery and a ground point on the frame. On other tractors I would get lesser voltage that wouldn't light a testing light. I don't know what the actual amperage would be.
 
I just changed the voltage regulator on the alternator that tested good. Just running a continuity test on the new volt reg the continuity to ground on the case was on the #1 spade and on the one in the alternator when passing the same continuity was on the #2 spade. That would be the one in the alternator when draining the battery.
 
Your 806 with alternator would be a negative ground setup, meaning the negative post of the battery is connected via the "ground cable" to the tractor frame. From frame to negative battery post you should see zero volts and not begin to light up a test light. If you are seeing 13 volts, the ground cable is open. Battery cable is either disconnected or the cable and/or clamps are extremely corroded, dirty or defective.

If frame to grounded post on any tractor or vehicle battery reads more than a small fraction of a volt you have a bad cable and/or connections.

The voltage from frame to your positive post should be nearly equal to voltage directly across both battery posts.
 
Thanks for bringing that up. I should have explained it better.

The 13 volt drain was from the negative post to frame with the ground cable disconnected from the battery. That's usually the way I check for a draw on the battery.
 
You are reading the battery voltage, which when looking for a current draw won't tell you anything. You need a current meter to put between ground and battery post. Do you have a current meter incorporated in your volt meter?

Another thing you could try is to unhook your alternator, leave battery connected and see if it continues to run down. If battery then runs down, problem is not alternator. If it does not run down then alternator is suspect.
 
That is NOT how and 806 is wired and the factory way worked well . when someone who does not know what they are doing and gets into the wiring with side cutters and a roll of RED wire and start rewiring you end up with problems . Forgive me but when it comes to wiring i get a wee bit OCD. as i have repaired many wiring harnesses and fixed many probelms to the point i can tell ya what color wire goes where on a 06 tractor . .
 
I would agree with that Vet. I think there may be some duct tape on this thing. I've had this tractor for over 25 years and no major problems. This charging thing is the first major headache, I think from the posts and what I have found it comes down to a bad regulator. It was probably burned out in the overcharging when the sense wire circuit failed.

I have hope and I appreciate the forum and all the help I've gotten.

Bob
 
Thanks for the suggestion, Rvirgil. What I have done is unhook the sense wire from the battery post on the the back of the alternator and put a volt meter between the negative post on the battery and the frame with the ground cable off the the battery. The voltage there reads zero. I hook up the sense wire to the volt reg spade #2 and the volt meter reads 13+ volts. I disconnect the battery wire to the alt post on back and leave the sense wire hooked to the #2 spade and the volts read 13 + volts at the battery post to ground.

I'm pretty sure this thing started with the sense wire circuit failing leading to the overheating alternator which upped the voltage to over 19 volts. That burned out the original voltage regulator and the new one I put in was grounded through the #2 spade.

Brownie suggested using an ammeter to get some more readings, which I'll do and post back. It looked like the regulator with the battery drain wasn't a Delco regulator. I got a new Delco and put it in. Just going by continuity I now have the circuit to ground on the #1 spade and the #2 spade is completely open.

We have this sub zero weather right now, but I hope to get it stuck back together see where I'm at today. I'll post back afterwards.

Appreciate it to no end, Bob
 
I will tell ya one more thing here on the wiring on a 806 , pull the hoods and check the main harness where it goes over the heat shield in ft. of the fuel tank . More then once i have found where the wires ware thru or short out INSIDE the harness in that area , sometimes the field wire gets into the main hot wire and it can cause the alt. to full field and over charge or drain the battery . Now as for a regulator i have been using a solid state one . Now as to the size of alt. on a 806 65 amps is more then enough as that will run everything even extra lighting . Also here if that main harness is bad i make up a new one and for the main wire i upgrade to and 8 Ga. from the alt. to the starter , depending on what all is on this tractor and if it is gas or diesel determens how many wires run thru the main harness . The FACTORY wire ends are of the Delco 56 sires and can be found at several places , myself i get all my wiring supplys from Terminal Supply and the branch i use is in Cleveland Ohio. I can get better wire of all colors and ga. size and the wire ends in bulk to cover the 14-16 and 10-12 in the 56 sires , I also get much heavier reg wire ends there then ya can find else where . Ya want to get fancy they have the Org loom to put the wires in . They also have the plug in connectors for most of what is on and I H tractor . Before warm weather arrives i will make my yearly trek up to restock .
 
"I got a new Delco and put it in. Just going by continuity I now have the circuit to ground on the #1 spade and the #2 spade is completely open."

Do you have a 3 wire or 1 wire regulator? I just replaced regulators in 2 of my alternators and got 3 wire regulators on ebay for under $10 apiece. On both I read about 5.8K ohms to ground on #2 pin and 40 ohms to ground on #1 pin. What range are you using on your ohmmeter?

Attached diagram shows 2 parallel resistors in series with another resistor from #2 to ground. No values are given on diagram, but 5.8K sounds reasonable. R6 from #1 to ground is 40 ohms and it's sole purpose is to provide a ground path for the idiot light.

Do you have a known good 3 wire alternator you could try? That might be easier than chasing all the rabbits.
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This post is getting a little old but I hope you are still referring back to it. Here is another thought on this. I think you said in an earlier post that you replaced the regulator in this alternator. Not questioning your mechanical ability but did you place the non-insulated bolt in the right position? Look at the video in the link go to the 5 minute mark. The non-insulated screw is in the 8 o’clock position which is the screw that is nearest the stator or outside of the alternator case. Not sure if this would cause your issue, but I know it will not work correctly if the non-insulated screw is swapped into the position of an insulated one. Also, note I am not suggesting you follow the suggested modification shown in the video it was just a place I found a clear picture of what I wanted to address. Video link https://m.youtube.com/watch?v=_DEXHd7v5kc
 
This is three wire. Battery post/sense wire (#2)/excite wire (# 1 with idiot light).

I just have the 1k setting on the meter. The #2 spade on the new volt reg is completely open and the #1 is 1250 ohms. That alternator is assembled, but hasn't been ran yet. This is the one draining the battery, had it checked = passed, changed the regulator.

I have a second alternator that I changed the regulator in. I had a marked Delco for that one. I have about the same readings on that one. The number two spade moves the needle slightly, you have to watch it really close.

Neither of these are known working for everything, yet.
 
That's a good point Used Red. I double checked that. I found a difference in the regulators that may account for the wrong spade being grounded. We'll see when I get things together. This subzero weather here is hanging me up a little. Thanks again, Bob
 
Just wrapping up this round:

I changed the voltage regulator to a Delco and have a diode in the excite wire. That stopped the test light from coming on at the battery to ground. This is with the battery ground strap off and the test light between the neg post and the frame. It charges fine with the jumper from the battery feed wire to the # 2 spade at just under 15 volts into a single 12 volt battery.

Still I have the 13 volts at the break of neg post to ground where the test light was. That still goes to zero removing the #2 spade connection. The ammeters I have aren't picking up any drain in terms of amperage. I understand this is the actual current, but I still can't figure out the voltage I'm showing at the battery/ground. It seems that should read zero. The other thing that's odd is the voltage at the neg post with the #2 spade connected is still there with the alternator off the tractor and not grounded. The only thing I have are the three positive wires of excite/battery/sense.

I did let the tractor set over nite with everything hooked up and it still reads 13.6 volts. Obviously that's still full charged. If I get another dead battery from this, I'm tempted to run that sense wire through a switched wire and see how that works. Then I'll know the #2 spade connection will be out of it.

As always, appreciate the help, Bob
 
"Still I have the 13 volts at the break of neg post to ground where the test light was. That still goes to zero removing the #2 spade connection."

It takes very little current to give a reading of VOLTAGE on a digital meter, likely, all is well.
 
That's a relief, Bob. Thanks. This sub zero weather up here takes the fun out of working on this thing.

Appreciate it and have a great new year, Bob (also)
 

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