testing a yanmar 2000 generator

[wbaggett]

I have a YM2000 and the battery will not keep a charge. I can jump start and it works fine. How do I test the Generator. I have a volt meter.

On the back of the generator, it has the Letters - E A and there is a plug that has the lettes N & F. What do these mean and how do I test it ?

I have tested the battery at Autozone and it goes dead after about 5-7 cranks. That is why I think it could be the generator or the voltage requlator. I wanted to know how to test the generator with a volt meter at the back of the generator and what kind of readings should I get. If the voltage requlator is the problem what pins to I need to test to see if I have 12volts. I have a wiring diagram for the YM2000, but it is not a very good one.

 

[Gatorboy]

<font color="blue"> How do I test the Generator. </font>

Have you considered testing the battery? You stated that the battery will not hold a charge.

 

[Bluecheck546]

Yep, what the ":: D A V E
:: g a t o r b o y " said ......... check the battery first. More that likely that is your problem. /forums/images/graemlins/smile.gif

 

[Tractors4u]

The voltage regulators on these tractors have a tendency to go bad. After all they are 20 years old. How long does the battery hold a charge? Enough to start it once or does it go down after a week of use? If it goes dead quickly, it is the battery if it takes a week or so then my guess is the regulator.

 

[cwarrix]

I'd take the battery down to my local Autozone or Advanced auto and have it tested for free and go from there /forums/images/graemlins/smile.gif

 

[wbaggett]

I have tested the battery at Autozone and it goes dead after about 5-7 cranks. That is why I think it could be the generator or the voltage requlator. I wanted to know how to test the generator with a volt meter at the back of the generator and what kind of readings should I get. If the voltage requlator is the problem what pins to I need to test to see if I have 12volts. I have a wiring diagram for the YM2000, but it is not a very good one.

 

[Soundguy]

5-7 cranks.. is that 5-7 times starting your tractor.. or 5-7 rpm? If 5-7 times starting the tractor.. that's all you can expect out of it if it isn't being charged.. if 5-7 rpm.. then yeah.. bad battery.

Put the vom across the battery. check static voltage. start the tractor.. what is the running voltage. If the running voltage is higher.. preferable 13-14.7 v then the alt/gen is doing its job. Static voltage should be between 12 and 12.6 or so. 12 and less is a 'discharged' battery.

Soundguy

 

[Jackbax]

Found this on a quick search for voltage regulator.

Regulator post

Look at the last post, Len explains how to check the alternator output.

Jack

 

[Darellk]

A fully charged should be between 12.5 and 13 volts. Like sound guy said, take a volt meter and read battery voltage with tractor off. This will tell you battery state of charge. Start the tractor and raise rpms to about 1000. You should see a charging voltage at least 1/2 to 2 volts higher than battery voltage. If you only see battery voltage ,your charging system is not functioning. Is this model a generator or alternator? If it's an alternator you could disconnect the voltage regulator and apply 12v battery voltage to the field circuit momentarily, at the alt. This will throw the alternator into a full charge mode. Don't keep it full fielded to long as it may fry some wires or the alt. if it is indeed good. If you see a good high voltge by doing this,then it is your voltage regulator or a broken circuit going to the regulator from ignition. You must supply voltage to the regulator from ignition for it to get the alt or gen charging. PS: If you are only getting 7 engine revs on cranking you really need to get that battery charged up fully before testing the charging system.

 

[wbaggett]

I had the battery charged at auto zone. I measured the voltage before I started the tractor it was about 11.5v, started the tractor and it was still about 11.5 v. I measure the volt at the back of the generator at the "F" connector and it was 6 volts DC. I measured the voltage at the Voltage Requlator and got 6 volts(pin 1 or 3), 10.5 volts(pin2), and 11 volts (pin 3 or 1). I unpluged the 2 pin connector from the back of the generator and measured 6 volts dc at the back of the generator. Is the generator or voltage requlator at fault ?

Any other tests recommended ? Thanks...

 

[California]

Been there done that.

I killed my regulator and consequently the alternator using a pressure washer.

You can take both components to AutoZone and they will test them for free. Tell AutoZone they came off a '72 Datsun (Nissan) so they can set up their tester properly.

This old post has the details.

 

[cwarrix]

</font><font color="blue" class="small">( I killed my regulator and consequently the alternator using a pressure washer.)</font>

I don't understand the part about the pressure washer??? Did it allow water into someplace it wasn't supposed to be, and fry things that way? I'm curious, since that was how I sprayed my tractor off last time I used it /forums/images/graemlins/shocked.gif Hope I'm not frying something!!! Thanks for any details.

 

[California]

</font><font color="blue" class="small">( I don't understand the part about the pressure washer??? Did it allow water into someplace it wasn't supposed to be, and fry things that way? )</font>

I looked at the regulator and saw the cover was sealed with a thick rubber gasket. It appeared to be water resistant. So I sprayed the space under the regulator to remove a mass of insect nests, dry hulls where something had hatched.

Next day I discovered I had washed the crumbling insulation off some wires under the regulator, which had aged because they were too close to the big power-dissipating resistors under there. That caused shorts and heat damage. The regulator was still dry inside but distorted from external heat.

That 20 year old regulator was mechanical with coils, relays, and the big external resistors. The replacement is solid state and potted in plastic so I think now only the connectors are vulnerable to water.

 

[cwarrix]

Thanks for the tip! I'll watch out for that next time I break out the pressure washer.

Those pressure washers are nice things to have but they sure can be destructive too. I once blew the chrome off the mirror on my old truck trying to wash off what I though was a spot /forums/images/graemlins/blush.gif Also blew the decal / labels off my Cub Cadet, but they weren't on all that good to start with.

 

[Darellk]

If you are only getting a reading of 6v you are reading stator voltage. the stator voltage on an alternator is half of output. It is possibleyou have taken out a stator lead internally so your output voltage is only 6v not 12+

 

[wbaggett]

Thanks for the sipport !!!!

I took the alternator to Autozone and it was bad.

Took the advice from this board and got a 1972 Datsun 510 Alternator (without a/c) and it mounted perfectly on the tractor. I also went ahead and replaced the voltage regulator (1973 Datsun 510 Part) and my YM2000 Tractor cranked right up and the new alternator is charging the battery.

Thanks !!!!!!

 

[wbaggett]

Thanks for the sipport !!!!

I took the alternator to Autozone and it was bad.

Took the advice from this board and got a 1972 Datsun 510 Alternator (without a/c) and it mounted perfectly on the tractor. I also went ahead and replaced the voltage regulator (1973 Datsun 510 Part) and my YM2000 Tractor cranked right up and the new alternator is charging the battery.

Thanks !!!!!!