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clemsonfor
Super Member
Rectifier on this tractor is external, it was replaced already.
Not Charging
- Thread starter clemsonfor
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rScotty
Super Member
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- Rural mountains - Colorado
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- Kubota M59, JD530, JD310SG. Restoring Yanmar YM165D
When I trouble-shoot a charging system that starts the tractor but doesn't seem to be maintaining the battery at full charge, I start with checking the battery & connections. We've been through that now in this thread.
Next thing I do is unplug the alternator from the circuit and hook my VOM directly to the alternator output leads to see if I'm getting AC or DC .... and to check if the output tracks RPM.
NOTE: Put the range selector on the VOM where it can safely handle at least 25 to 30 volts. Use a 50 volt scale if it has one.
Who wants to chime in with where to go from here?
rScotty
Next thing I do is unplug the alternator from the circuit and hook my VOM directly to the alternator output leads to see if I'm getting AC or DC .... and to check if the output tracks RPM.
NOTE: Put the range selector on the VOM where it can safely handle at least 25 to 30 volts. Use a 50 volt scale if it has one.
Who wants to chime in with where to go from here?
rScotty
OP
clemsonfor
Super Member
Grounds and connections were clean. That was done. Promise. I am not sure if I was getting AC or DC on the progs of the alternator. I was checking one of them on the connection. I was getting upwards of 20+v on the DC scale. And it did track with RPM. The other connection on the 2nd prong at the alternator didn't have anything or if I remember at this point it was 10-12v I'm thinking it was battery voltage.
Please post the whole diagnostic chart if you would like I'm sure it would help someone who is not an expert in what connection at what spot on the back of the alternator should be showing what voltage. I just know it wasn't charging as I was showing battery voltage running at the batter wire on the alternator and obviously the same at the battery itself. I was not charging. One connector on the back of the alternator was showing close to 20 so I assumed alternator was good. I am pretty good with this but not an expert. As you see. I'm happy at this point it's fixed. No headache parts are new alternator and regulator and I have about $50 in it all. And probably a good regulator I took off for the shelf. I'm sure im good for another few decades. Long enough I will forget all this I'm sure.
Please post the whole diagnostic chart if you would like I'm sure it would help someone who is not an expert in what connection at what spot on the back of the alternator should be showing what voltage. I just know it wasn't charging as I was showing battery voltage running at the batter wire on the alternator and obviously the same at the battery itself. I was not charging. One connector on the back of the alternator was showing close to 20 so I assumed alternator was good. I am pretty good with this but not an expert. As you see. I'm happy at this point it's fixed. No headache parts are new alternator and regulator and I have about $50 in it all. And probably a good regulator I took off for the shelf. I'm sure im good for another few decades. Long enough I will forget all this I'm sure.
rScotty
Super Member
- Joined
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- 8,258
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- Rural mountains - Colorado
- Tractor
- Kubota M59, JD530, JD310SG. Restoring Yanmar YM165D
I'm glad yours is fixed and working. But there will be another owner with a challenge, so I hope this thread helps them too.
Just how one learns - and then teaches - the troubleshooting of electrical systems is still a mystery to me. I'm hoping to learn that art myself someday.
As for diagnostic charts - the ones that I have seen are either too simple to be useful, or are so complex they only work with the particular circuit they were designed for. There is really no chart that can substitute for a basic understanding of how charging circuits work.
By the way.....VOMs do vary in quality. Might as well get a good one. A good one - like a Fluke - will always have a way to tell AC from DC before the wrong assumption damages the meter.
When learning, I found it helpful to build up that basic understanding by realizing that all of the various motor/generator/battery systems are doing the same thing, and they do it in pretty much the same way.
Luckily, they all have only a small handful of similar parts connected up to accomplish the same simple goal - which is simply keeping a battery charged.
The only real difference being in a few details. With a little practice and study you will figure them out.
Don't be shy to ask dumb questions when you come to a mental roadblock.... Doing that sure helped me to learn this stuff.
Just how one learns - and then teaches - the troubleshooting of electrical systems is still a mystery to me. I'm hoping to learn that art myself someday.
As for diagnostic charts - the ones that I have seen are either too simple to be useful, or are so complex they only work with the particular circuit they were designed for. There is really no chart that can substitute for a basic understanding of how charging circuits work.
By the way.....VOMs do vary in quality. Might as well get a good one. A good one - like a Fluke - will always have a way to tell AC from DC before the wrong assumption damages the meter.
When learning, I found it helpful to build up that basic understanding by realizing that all of the various motor/generator/battery systems are doing the same thing, and they do it in pretty much the same way.
Luckily, they all have only a small handful of similar parts connected up to accomplish the same simple goal - which is simply keeping a battery charged.
The only real difference being in a few details. With a little practice and study you will figure them out.
Don't be shy to ask dumb questions when you come to a mental roadblock.... Doing that sure helped me to learn this stuff.
OP
clemsonfor
Super Member
Y
YeS full diagnostic flow chart for diagnostics would be great. I usually an tinkering with newer stuff than this. They have internal regulators. So you diagnose the alternator as not working, at that point it doesn't really matter if it's the internar regulator or something else that part is bad.Oh, we can't just call this thread coming to a close. There is still so much of this electrical stuff to be uncovered for charging.
California
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- Yanmar YM240 Yanmar YM186D
As rScotty and bmaverick noted, it will be helpful to owners in the future if we accumulate what we know into a diagnostics thread.
For YM186, and other 80's Yanmars with the pancake alternator and diodes external, I posted a test diagram in Post #7 of this thread. The thread also discusses the earlier pancake alternator with internal diodes.
And here is the YM186 wiring diagram, that uses that alternator. The diagram is likely applicable to similar Yanmars.
careyo63
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- 77 Yanmar YM2000 63 Ford 2000
Pretty straight forward still on a YM 2000. My dash light would flicker!! Chased that for months and finally stumbled into it. Loose bad connection on my fuse panel. More corroded than I would have thought. That was more of the problem. Still ? how I found it!!...... Drove me nuts... Here is the 2000 dia. I just had out for anyone who may need it!!!!
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clemsonfor
Super Member
Something I suspect to be the case but I am not sure is that your charge light does not come on till voltage is below a certain level, even if your not charging. My light flickered and then was on if I remember right. But once I charged the battery even though I was not charging my light would not be on. When I caught it the battery was pretty low 50% or less if I remember. So untill your total system voltage drops below some level I don't think that light even comes on....it's nothing to do with you charging I believe just a set voltage level. At least that's my suspicion from the poking around I have done. Both regulators kept it off too. But the battery was right around 12.6 resting so it was almost full
careyo63
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- 77 Yanmar YM2000 63 Ford 2000
I just changed my battery of 13Yrs. which is still good since I didn't kill it. Which one thing I did notice going to a 700 cca. is that if my Rpm's. get below 800 my Alt. light will flicker. Barely bump the Throttle and it stops. How I found this out is if I'm shifting a lot with the mower on I'll run 2nd. PTO. so shifting is easy and I set my Eng. Rpm's as low as I can without the Mower in gear. It has always seemed to Gradually increase Rpm's a few hundred but not much