Yanmar Tractor Support Message Board

Winston,

I first just plugged in the new regulator, then when that didn't work I took my plug apart on my tractor and matched colors with the regulator plug. Of course, that did not work either.

Does your colors match? Does the two blues from the alternator match the two blues on the regulator?

Does anyone know how to test the regulator to check the voltage output at the plug?

Yes, the 2 blues from the alternator do match the 2 blues on the regulator. The way I checked out put from regulator was to insert voltmeter probe on top side of plug. You should be getting 12.5+ or so depending on engine speed. If you check on top the blue you should get your 20 or so ac volts. If you are getting the 20 or so ac and not 12.5+ dc you have a regulator problem. Either wrong regulator or bad regulator. The wire in between the two blue wires match up with regulator wires but the 3 on the other side of plug do not match up. After my research on the black box (thermal start control) I am convinced it has nothing to do with the regulator other than getting voltage from it. I had spoken with one of the Hoye sales people at my time of problem and we had agreed this black box you have the picture of and the black box used with some regulators are two separate animals. Hope this makes some sense. P.S. Do you have a thermal start light on your tractor? If so and it works try unplugging the black box and see if the thermal start light goes out.

I'm not real sure what to do next. I cannot get voltage out of my regulator. My old plug only has 5 wires not 6. I would think I could get the voltage out of the regulator with just the 2 blue wires connected. Since I cannot, I assume that the new regulator is bad. I also assume it is the correct one. Any suggetions on what to do? I guess I could buy another regulator, but I fear it may not work either, but I don't understand why I am not getting the DC voltage out when I am getting AC voltage in.

What to do????

If it were mine, I would either get a new regulator and start over, (assuming you are still getting good ac voltage from the gen, if that is even enough. I always heard it should be 22-30vac), and don't mess with trying to match up wires, just plug it in, or try this.

"If" the blue wires on your new regulator are the "correct" terminals to match up with the blue from the alternator and you are not getting any dc voltage out of the regulator, it would have to be a bad regulator. However, since the regulator is completely different do you think blue might not match up with blue? Does the new regulator plug match the tractor plug other than one extra wire? I still lean toward the new regulator not being the right one for your application. If there is no return on it I would probably experiment with going in on different terminals with the 20ac volts to see what happens.

All vendors seem to agree that the VR-522 reg. is the correct one for the YM2020.

As usual Norm, you are right, most any Yanmar in that size range seems to take the 522 regulator.

It apparently depends on the model. All of these, 195, 240, 330, 336, 1700, 2000, 2200, 2210, 2500, 2610, 2700, 3000, 3110, 3810, 4300, probably older tractors, take the VR-550. In these the gen. has the rectifier, and puts out DC voltage. These are the ones that use the '72 Nissan/Datsun gen./reg.

The new regulator plug does not match wire colors with the tractor plug. If I remember correctly, I don't think any match. The black wire on the new plug matches up with the empty space on the 5 wire tractor plug. I could try to experiment with it. Plugging up the regulator the first time may be what messed it up, but I thought it would be a direct plug in. I guess at this point I have nothing to lose. The gamble would be buying another regulator and doing the same thing. I assume everybody believes that if I buy another regulator and put the two blues to the two blues that I should get DC voltage out. I may buy another, but I need to make sure if possible.

We have sold hundreds if not thousands of those regulators and you just plug them in and move on. There is no color matching or rewiring required. They are very reliable. One thing i do not understand is why your tractor plug has only five wires where the wiring diagram shows six. It is probably just the ground and the regulator may still ground through its frame as long as the metal is clean.

_________________
Aaron
Contact Me
(940)592-0181
http://www.HoyeTractor.com

Aaron,
On all these that just plugged up, did the alternator blue wires go directly to the (thermal start) box like it does on my tractor? This is what confused me first because this does not match the wiring diagram. Second was the wire colors that don't match the new regulator plug, especially after I plugged it up and it did not work.

It would be nice if I could see I tractor or if someone that has one like mine new if the 2 blue alternator wires go to the two blue on the regulator or if it went to others. I am afraid that if I buy a new regulator I will "mess up" the second one if I wire it wrong.

The instruction say the Vr-522 regulator plugs directly into the alternator, regardless of whether you need the aux. harness or not, since the reg. now contains whatever is in the black box. I'm sure if that were not true there would be chaos in the entire Yanmar parts industry. It's always possible you have other problems. I would put everything back original and start from scratch.

I don't know. I have never had a need to research it because there has never been a problem before. I will do some digging and see what I can find out though.



I agree that there are several things on your tractor that do not seem to match the wiring diagram. You are SURE that it is a YM2020?

_________________
Aaron
Contact Me
(940)592-0181
http://www.HoyeTractor.com

Aaron,

It says 2020D on the hood. The guy I bought it from a couple of years ago said that it was. How can you tell?

www.hoyetractor.com/serial.htm

I think the 2020 may just say "20D" though.

_________________
Aaron
Contact Me
(940)592-0181
http://www.HoyeTractor.com