YM1100D electrical issue

[kwms56]

I've owned this tractor for about 30 years, and ever since acquiring it the charging system (really the whole electrical system) has been a complete wreck. Have always just kept the battery charged up with trickle charger. That's now changed; recently I did a lot of work on the tractor and basically redid EVERYTHING electrical. Good news is that everything now works, and I added some accessory items: light bar mounted on ROP frame, digital volt gauge, accessory "cigarette type" plug.

Here's the problem: I'm getting between 16 and 17 volts produced by the generator going through the voltage regulator/limiter. Way too much. This machine has a 3-wire regulator with yellow, red and black. Black goes to ground. Yellow ties into yellow wire coming from the gen. Red connects to ignition switch and gets power when switch is in "on" position. I have notebooks full of manuals that came with the tractor, and I've followed the wiring schematic carefully. The regulator is new, and supposedly it's the correct one for the tractor.

Any ideas would be appreciated.

 

[winston1]

Pretty sure your dynamo puts out ac voltage and your rectifier/regulator converts it to dc voltage. Are you aware of that? It should put out 15 to 20 something ac volts depending of speed.

 

[ponytug]

@kwms56 Welcome to TBN, and congratulations on getting the rewiring done and improved.

My bet is that @winston1 is right, you are measuring AC, and the system is ok. How is the voltage after the regulator?

All the best,


Peter

 

[careyo63]

Should be a Factory Dyno., With all the added lights and Gauges. I would change to a Alternator. I've seen several times that people used a GM style Alternator with a built in Regulator. Then you can Run it straight to the battery and then leave all the Wiring to the Tractor intact! Your Charge/Alt trouble light won't work correctly or at all or that matter. Just add gauge to it.

 

[rScotty]

I agree with Winston. It sounds almost like ou are measuring AC voltage from a decent dynamo right at the dyno outputs - and it sounds like that AC voltage is about right. In fact, AC output from the dyno at working RPM could be a little.higher and still be OK.

What matters most is the DC voltage delivered to the battery.

Try this: Measure the DC voltage across the battery terminals before you start the motor some day and then again across the battery terminals with the motor running.

The first measurement after the tractor has set overnight should be somewhere around 12.1 to 12.8 volts depending on the health of the battery....and the second measurement with the engine running at normal working RPM is generally somewhere in the range of 13 to 15 volts DC - though I've seen them higher than that & the only downside is a shorter life for the lights.

The charging voltage always has to be a little higher than the battery voltage for charging to take place.

rScotty

 

[careyo63]

Battery cable connections on the YM2000 Yesterday. Cable connector at the Pos. terminal. Cleaned and replaced it. Actually happened several times over the 17 Yrs. I've owned it. I seen my Alt. trouble flash. Thought it was kind of slow cold start. It was in the 40's earier. The battery showed up 12.2V. and after I started and check it 14.25.. Don't get any better than that at Idle, Check the AC when it gets cold kind of normal They work On a diesel no power needed to run it just enough to start it. And that's barely AC when it gets cold out.

 

[bmaverick]

 

[kwms56]

Thanks to the two responders to my issue; much appreciated. We had some ugly weather over the weekend from the noreaster in NC, so it wasn't until today that I could get more voltage readings and supply a few photos.

I'm pretty sure that I'm getting high VDC. In my recent rework of electrics, I installed a digital volt meter on the dash. For the sake of photos, the captures are flickery. The one that I do show kind of close up is displaying 16.3 VDC at roughly 1/2 throttle position; I don't have a tach. This volt meter is from ground to one of my "out" wires from the new fuse box installed. I think it's my headlight circuit, but it really should not matter. At the same time I was seeing this, I opened the hood and took a reading directly from the battery posts using my multimeter set to read 20 VDC. What I got there was within .2 volt of what I got on the dash-mount meter. If I throttle up, the volts go up to about 17.5. If I go to the lowest idle, I get around 13.7. Of course if I turn on lights, my new light bar (with two LED forward mounted lights and three rear-facing red and amber LED lights) or press the thermostart button, then the volts go down.

I'm thinking about the only possible issue must be the voltage regulator/limiter. As pointed out in my original post, there are two wires coming from the generator: one is red and one is yellow. The regulator has three wires: red, yellow and black. The regulator is new, but it might not be good or it could the wrong one although the supplier said it "should" be the right one.

As for the gen wires, the yellow is supposed to go directly to the yellow regulator wire...and it does. The red gen wire goes to the post on the starter solenoid (shown on one of the other pics) where the + main cable from battery also goes. The red wire on the voltage regulator goes to the IGN terminal on the key switch. This wire gets voltage when the key is in the ON position. And lastly the black wire on the regulator goes to ground.

Compared to many set-ups, this one is pretty simple. Two wires from GEN and three wires from regulator. But in the end, I'm getting upwards of 17 volts (and pretty sure it's DC and not AC) instead of what I'd expect...something less than 14 VDC).

So with this additional info, anybody have any other suggestions about what the problem might be or any other tests I might run?

 

[ponytug]

Do you have a digital voltmeter besides what is in the dash? If so, can you show the readings on the input and output of your regulator compared to the battery negative?

While it is possible that there is something off with the regulator (e.g. broken wire, or disconnected internally), I personally would be more inclined to question the dash meter. Can you connect the dash meter to something that you know is good, e.g. the battery directly?

All the best, Peter

 

[kwms56]

In my response earlier I described the voltage reading from my new dash-mounted voltage gauge (16.3 VDC at about 50% throttle) and at the same time measuring the voltage on the two battery terminals with my multimeter set for 20 VDC . The dash gauge and the multimeter were within .2 VDC of each other.

I considered the alternator course of action and would prefer that, but I have not found a bolt-on option. Can anyone point me to a source to purchase? There really isn't a clean way I can find to mount and drive a stand-apart alternator. Need something that can mount in place of the present generator.
By the way, this tractor does not have any sort of charging/discharging idiot light...and never did so far as I can tell. There are oil pressure and coolant temp idiot lights, and I changed those from incandescent to LED in my recent rework.