Alternator test

[shameless 3]

Hi Guys:

I want to make sure that the charging system is working correctly on my 312-8.

My neighbor wanders over and says

" we used to test a charging system using a multimeter, but I don't remember how we did it"

I forgive him he is 80 and does come up with some great ideas.

Any one out there used a multimeter to test if the charging system is working??

:ychain:

[Trouty56 565]

Well how I do a quick check is check the battery voltage when the tractor is not running and then check it after it is running at like 1/2 throttle at least. Probably get 12 volts plus something before and should get a little over 14 volts after it is running.

[shameless 3]

Hey Trouty:

Thanks for your response.

I think your test will show voltage not current.....

I guess I should have asked "how to check an alernators current output".

Sorry for not being more specific.

I have some plans to add stuff that will create an electrical demand and want to be check the charging capabilities first.

Anyone in the wheelhorse world know how to check this with a multimeter?

[Trouty56 565]

Haha...well I tried. Some of these guys get it right down to the amp. Horsefixer has done some wild experiments with lights so he may know about measuring current output.

Luck to ya!!

[shameless 3]

Thanks Trouty 56:

I hope that Horsefixer chimes in.

[rmaynard 14,932]

What year is your 312-8? Some 312's only have a 3 amp alternator.

[shameless 3]

Hey Maynard.

Its a 1988.

[rmaynard 14,932]

1987 owners manual states that the alternator is 15 amps regulated. The 1990 manual states the same. I'm still looking for the '88 manual to confirm that it is the same. The 1986 had a 3 amp unregulated alternator.

[rmaynard 14,932]

The only thing 1988 that I can find is the wiring diagram. It shows a 15 amp fuse, so...I would be inclined to limit my total amperage draw to under 15 amps.

[shameless 3]

Hey Maynard.

I did a bit of research as well and found that the 312-8 was available with a host of optional charging systems.

from a rectified 1.5 or 3.0 amp system to a 10 to 30 amp system.

Thanks for helping out!

[TT-(Moderator) 1,128]

As far as I know, the 312-8 either had a 3 amp non-regulated alternator (diode-rectified with separate 70W lighting coil on the 1985/86 with the K-301) or they had a 15 amp regulated system. (1987 to ? M12 Magnum)

[shameless 3]

Hey TT:

Thanks.

Mine has the Kohler Magnum 12 and I know I saw a fuse when I was checking the wiring and its 15 amp.

How can I test to see if its producing 15 amps

[TT-(Moderator) 1,128]

Some of the on-site electrical geniuses may laugh hysterically at this answer, but I guess you'd have to "splice" an ammeter into the wire going from the B+ terminal of the rectifier/regulator to the ignition switch, and then apply enough load to the battery to force the alternator to produce the maximum output.

Whether that testing procedure is correct or not, it's probably not a good idea to load the alternator close to the maximum output for long periods. You'll either toast the rectifier/regulator or the stator - or both.

I installed a dusk-to-dawn pole light next to my driveway years ago, so tractor lighting has never been a concern of mine. As a matter of fact, I prefer using tractors that don't have batteries. :ychain:

[Trouty56 565]

Shameless,

I found a parts manual and uploaded it to the documents area if you are interested. It does show a 15 amp stator on the Kohler. The file needs approved yet but it is here.....of course, that is, if you are interested.

[shameless 3]

Hey TT:

I don't know if the "onsite electrical geniouses" have the right to laugh at your answer.

I have not seen a reply from those experts yet.............Are any of them out there???

I will try a voltage test first as Trouty56 suggested earlier.

Thanks

[shameless 3]

Hey Trouty:

Thanks for the manuals.

The Cover page states "Parts and Service Manual"

It is a parts manual, no service instructions.

I did need it though for parts reference.

Thankyou!

[Trouty56 565]

The Cover page states "Parts and Service Manual"

It is a parts manual, no service instructions.

I noticed that too....I didn't create it...I just passed it along....lol. Glad it was helpful for ya.

[rmaynard 14,932]

Hey TT:

I don't know if the "onsite electrical geniuses" have the right to laugh at your answer. I have not seen a reply from those experts yet.............Are any of them out there???

The so-called geniuses haven't been around lately.

I thought TT's answer was pretty good myself. I was going to suggest that you keep adding "load" to the circuit until the 15 amp fuse blows, then you will know your limit. The fuse would protect your stator and rectifier/regulator from overload.

I don't know if this is possible on the 312-8, but it has been done before on some C-series. If you had access to a 30 amp stator & flywheel, you could install them and two 15 amp regulator/rectifiers. One circuit could be used for normal tractor functions and the other for accessories.

:twocents-02cents:

[shameless 3]

Hey Maynard:

I thought I would take a poke at the "geniouses" in hopes that they may respond.

I think I will try Trouty 56's method first which will tell me if the system is charging, that is simple and easy and only requires lifting the hood and connecting the meter to the battery.

If its charging I can check on the current output using TT's method, sort of.

I have an ammeter guage I bought for my boat and never used it.

I will connect it up in place of the volt guage and be able to see the current any time.

Thanks so much guys.

[shameless 3]

I should add.

The need for electric power is for future use.

I plan on motorizing the blower lift as well as chute rotation and deflector.

This will require a heavy duty actuator, a light duty actuator and a small motor.

Since all 3 will be used everytime I use the machine I know it will require a functioning charging system due to the small capacity battery.

Thanks again guys!

[pfrederi 17,171]

Hook up the ammeter as TT suggested then with the engine off run the battery down a lot by leaving the lights on (not stone cold dead but down until the voltage is below 12 (fully charged is 12.6). Then start it up and see how much the ammeter shows. A low battery should prompt the regulator to put out its full capability.

[shameless 3]

Hey pfrederi:

Thanks for the response, makes perfect sense.

I though of doing this for the simple test just off the battery measuring voltage, it would make it easier to see the change in voltage form a lowered battery voltage.

I thought of draining it down to around 11 volts measured and then start it.

Thanks for your help.