replacing generater with alternator

g707

Member
I am putting a delco-remy 10si three wire alternator on a1965 john deere 4020 positive ground so i bought a positive ground alternator i hooked the main lug to a volt gage and from that to the battery ihook the number one terminal (exctire) wire to the switch for the hot side of the coil and i hooked the number two terminal (sense) line to the battery this should be right but it does not seem to be charging the only thing i can thing of is the tractor engine rotates counter clockwise were is my truck rotates clockwise could that be the problem or does it mater which way it spins thank you
 
The jd tractor engine rotates clockwise when viewed from the front as does the pickup engine.Why do you say it rotates counterclock wise.It would make a difference if that were true.Explain your thinking on rotation.Must be a different problem.
 
Rotation shouldn't make any differance on an alternator. By the way they are built, it should charge either way.
 
As long as all three on the alternator are hooked to positive in some way, it is supposed to charge. #1 is supposed to be switched and if in the ignition circuit, you need a diode. Otherwise, once the alternator starts charging, it will keep feeding the ignition -even if you turn the ignition switch off. #2 can go to the battery if you want, but not necessary on a tractor. You can hook #2 to the main output post on the alternator.

As far as rotation goes? I never thought about it much, but doubt it would make a difference. The moving parts in the alternator make AC current, not DC and I think it will work in either direction. But, your tractor turns the correct way anyway.
 
Rotation makes NO difference. I put a Delco alternator on my B John Deere. Quicky bracket made it sit backward. My only worry was would it overheat, but over 30 years now and it still works. It does have an external regulator.
 
setting in the seat it runs counter clockwise setting in the seat of truck it runs clockwise but from what the others say it should not matter just some thing i noticed
 
It should still charge regardless of direction. An electromagent (rotor) still rotates inside the stator (armature) and AC voltage gets induced.

NOTE: In the Excite circuit from the ignition coil input (or ign switch output) to the No 1 terminal on the alternator I RECOMMEND A 10 OHM RESISTOR as it provides at least some degree of current limiting protection PLUS (similar to why some use a diode) it can prevent run on when the tractor is shut off if the alternator backfeeds the coil. PS if you happen to use a diode (you didnt indicate you did???) ITS POALRITY SENSITIVE AND NEEDS WIRED CORRECT or it doesnt supply excitation current !!!!!!!!!!!!

The No 2 voltage sense can work wired to the battery, many people simply jump it to the alternators big output stud.

John T
 
Did you truely hook up the main output lead(heavy wire) to a Voltmeter (or was it really an ammeter?)

If this is a Voltmeter, the internal circuit of the meter is very high resistance, and so it won't pass current to the tractor's circuits. A Voltmeter is good only as a measure of voltage between "hot" and ground. A Voltmeter might be used in this circuit if both the heavy input and output wires are connected to the same lug on the meter back. Then the other lug needs to be connected to ground. Now it measures Voltage (0 to about 15) and conducts the amperes right through the 2 heavy wires.

Now if that electrical gauge on the dash is really an Amp-meter, then one heavy lead is connected to one lug, and the other heavy lead is connected to the other lug. The current (amps) flows right through the meter with close to Zero resistance. The meter is a heavy duty conductor. The meter face will probably read -40 <0> +40, or maybe even bigger numbers. If you really have an ammeter in the dash, and the alternator is wired correctly with the activation wire coming from the run position on the key switch, then the alternator should produce current (lights bright, battery charging, etc). One quick test for this on the SI 10 is to locate a D shaped hole in the back of the alt. Inside of that hole is a metal tab that can be pushed "in" with a small screw driver blade or a nail. Push it with the engine turning at a medium idle (maybe 1000 RPM), but first turn on the headlights. The lights will look a bit yellow if the alt does not charge, but will instantly become bright white when the alt kicks in as you push the tab.

Good Luck

Paul in MN
 
Another thought.... Did you remove the generator's regulator? If that regulator is still in the wiring circuit, it will not pass the current to the tractor as it did with the generator. Solution... the 2 heavy wires (maybe on opposite sides of the regulator) must be hooked together (use Batt terminal of regulator and put both battery wire and alternator wire under that same screw). Now you will have bypassed the regulator and it is out of the circuit, but still useful as a junction block.

Paul in MN
 
I unhooked regulater wires and run all new wires to desierd location and i did use a diod on the exciter wire and i even hooked it up with out the diod and the tractor shut off fine i also put a new voltmeter on but i might of had it wired wrong i even put a old ampmeter on that worked when i took it off of another tractor i geuss my next step is to have the alternator tested even if it is brand new i wounder if autozone can test a positive ground alternator thank you for all the good advice
 
NO reason to think he didn't get what he asked for.

If it IS NOT a (+) ground alternator and he hooked up the battery (+) ground he would have had LOTS of spark and probably let some smoke out, as well.
 
Of COURSE it shut down just fine without the diode, 'cause the alternator isn't charging.

Once you have the alternator working,you WILL need to diode.

Of course, the diode will be REVERSED from this photo, 'cause your system is (+) ground.

<img src = "http://www.gondtc.com/~blweltin/Bob/AlternatorHarness4.jpg">
 
Paul, there's no tab to "push". It's SOLID and does not move. What you are actually doing is SHORTING the tab to ground to "full field" the alternator.
 
"setting in the seat it runs counter clockwise setting in the seat of truck it runs clockwise"

WHY not take a minute and re-think that statement?
 
I just took a minute to re-think MY statement and I'm thinking YOU are correct.

On your tractor, the generator/alternator shaft points BACKWARDS towards the driver, doesn't it? THAT'S what makes it rotate backwards, the ENGINE rotates in the standard direction.

As far as the alternator is concerned it is NOT rotation-sensitive.

HOWEVER, the alternator's pulley is NOT keyed like the original generator's pulley was and will tend to unscrew the nut over time.

Once it's working, I would take off the nut and pulley and put some high-strength Loctite on the shaft, just to be SURE the pulley's not going to come of, POSSIBLY getting tangled up in the fan in the process.

A 3/8" impact gun and a 15/16" socket work GREAT for this.
 
Bob,

Thanks for settin me straight on that point. I knew the memory was a bit hazy on how that worked, but I have done it, and it does work.

Paul in MN
 

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