Yanmar Tractor Support Message Board

Is there a way to test the regulator to make sure it is putting out the correct DC voltage? My battery does not seem to be getting recharged. It seems to hold the voltage, but after several crankings it will eventually not have enough voltage to crank the engine. I have measured the AC voltage coming out of the alternator (dynamo) and it is anywhere from 13 volts to 20+ volts depending on the rpm. The two wires coming out of the alternator go to a box beside the regulator that says W11-07 (see attached picture). I am not exactly sure what this is or why this does not go straight to the regulator. I changed the regulator with a new one but it did not change anything. Seems like the wiring is different than it should be but it was working until recently. Does anyone know what this box is and how the wiring works going through this box? What should I try or do?

Thanks.

The wiring diagram shows the alternator running right into the regulator - no pitstop at a mystery box. That part does not really look factory. Does it look like you could unplug it and plug right into the regulator instead? Sort of looks like the plugs might be the same?

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Aaron
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I have that same box on my 2002d. I recently had to change my regulator and it fixed my problem which was same as yours. The way I checked mine before buying the new regulator was to check the ac voltage at the plug where it goes into the regulator. Had the same 20 or so ac volts that you do. I then checked the output voltage of the regulator and only had about 12 or so dc (same as battery voltage). Should be 12.5+. After installing new regulator I had 12.5+ depending on engine speed. If you have already changed the regulator I suppose it could be something else. This is the regulator that fits mine. This sight shows this regulator should fit yours also. Are you confident you have the correct regulator?dwhounsI http://www.hoyetractor.com/mm5/merchant ... 02ELECTRIC

Well Aaron, your post beat mine a couple of seconds. You sold me the regulator for my 2002d and I have his same little box. Everything worked fine. His regulator definitely doesn't look quite right.

I guess I just never noticed that before. Wonder what it does? Can't find it on the wiring diagrams anywhere. 2020 wiring diagram attached.

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Aaron
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Looking at the wiring diagram in my 2002d operators manual it looks to be a glow control (thermostart). I may unplug mine and see if the thermostart quits working. Well, I'm back editing. It has nothing to do with thermostart. Thermostart works with or without it. Beats me what it is for.

You can use the tractor in the meantime if you shut the key after it starts. You won't have lights/instuments/horn, but it will run without draining. Just charge it after every 5-20 starts (depending on the battery).

I tried to completely take the mystery box out of the equation. The new regulator has two blue wires. The alternator has two blue wires. I plugged the two blue wires to the two blue wires. I put the black wire to the black wire. Shouldn't I be able to read 12.5+ DC volts coming out of the red wire on the regulator plug? I did not. I can't read much of any voltage until I hook the red up and then I am reading the battery voltage. Did I hook it up correctly? I am not sure what to do. Could I have a bad new regulator?

The old regulator and the new regulator wires are different. The old regulator has 5 wires the new has 6. The colors also do not match up with each other.

I think you have the wrong regulator. You need the one shown in my earlier post. Look at the wire colors on it and see if they match your wires.

I have noticed before that the wire colors are not always the same so I would not go by that. The wiring diagram for the 2020 (posted earlier) shows 6 wires.

There are only two 6 wire regulators that yanmar uses. One has aluminum fins the other is a flat black rectangle. As long as you got the aluminum fin version with the 6 prong plug it is correct.

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Aaron
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Winston, my new regulator looks like the one on your post. The one in my picture is my old one. The wire colors with the new do not match up with what I have.

Aaron, since the wires did not match up both in color and amount from the old (5) to new (6) that is why I put the 2 blue from the alternator to the two blue on the new regulator. The black to the black and the red (to the startor/battery) to the red. I did not hook up the others. I was hoping I could test with a volt meter to see if the regulator would put out 12.5+ volts. Do you know if this is correct? Can you test the regulator this way? Can you tell from other tractors if this is correct?

Thanks

Curiosity killed the cat! "meow". I had to find out what that black box is so this morning I traced 2 of the wires with an ohm meter to the little red light on my dash which is the thermal start light. The light has never worked. After doing this I removed the little black box. I could hear something rattling in it so I proceeded to take the box apart. Nice little circuit board inside and some little three pronged looking deal had come loose inside. I proceeded to put it back in place, put the box back together, plugged in and guress what? The thermostart light now comes on and will cut off automatically after about 10 seconds. So, for what it is worth, the little black box is a thermal start cut off. RCBooth, I was mixed up about new and old regulator but it still seems to me you have the wrong regulator. When I replaced my regulator the wiring plug was a perfect match. Did you take loose your plug to change wires?

I believe that new regulator requires a wire harness to bypass and eliminate the black box.

In his picture it looks like he has the correct 6 plug terminal though. The adapter harness is used when you have an older model with a 3 plug terminal going to the regulator and a 2 plug terminal going to the "black box". The harness just Ys the two together to the new rgulator's 6 terminal plug--

You can see the adapter here-



http://www.hoyetractor.com/mm5/merchant ... ode=wh-522

.

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