B6000 Battery Charging Problem

[KuB6000]

As mentioned in a prior thread, my battery will hardly turn the tractor over.

I measured the voltage from positive to negative terminal with the tractor off and the tractor running at high RPM. There was no difference in voltage. Just for kicks, I took the positive terminal off, and measured the voltage while running. It was 0.3 volts.

I then unplugged the dynamo from the wiring harness, and took voltages across all three wires while running at wide open throttle. They were always been 28 to 30 volts. I understand from another forum that it should be 43 volts between brown and white and 30 between brown and yellow. Is this true or false? Is 30 volts too low between B & W? These are all AC voltage measurements.

To complicate matters, someone has rewired my machine and did not follow the wiring diagram. Tell-tale clues include the fact that no wires go to the light switch, and some amateurish type splices. It wouldn't surprise me if my charging problem is related to a bad splice.

If I don't care about having headlights or a horn, what is the simplest way to wire this tractor and make it work? I think it would be a real chore to trace all of the wires and wire it up as per factory.

Is there any way to test the rectifier?

Thank you,
Chris

 

[KuB6000]

I thought I would update this thread with more information:

- the wiring diagram is attached. As mentioned previously, mine is wired different than the diagram.

- the brown wire from the Dynamo is hooked to one of the AC terminals on the rectifier
- the other AC terminal on the rectifier is hooked to the battery
- there are no other connections to the rectifier
- there is no continuity between any of the connections on the rectifier regardless of the polarity.
- I suspect this means the rectifier is no good.

I will confess that I still don't understand rectifiers, but based on what I know, I suspect the charging system probably never worked wired in this fashion.

Chris

 

[KuB6000]

I've had the new battery in it most of the day (without the charging system disabled). I've started the tractor half a dozen times. Had to use the glow plugs a few times. The battery is still reading 12.8 volts.

I think I will put the trickle charger on the tractor at the end of the day, and call that my charging system. I don't think I need anything more than that!

Chris

 

[Michael]

I am thinking that when Vic gets back on that you might see if he can source you a junked out B-series tractor's wiring harness and you replace the entire wire harness this summer.


When it is cold this winter and you got a bunch of snow to remove from the driveway and it is after dark that you will want a properly operating charging system with lighting to see the task at hand. In my opinion it is just the fact that having a properly working charging system is as important on your tractor as it is on your car.

Actually if you have the wiring diagram you could actually build your own wiring harness. It is not really all that difficult you just need lots of different color wires.

 

[Rich C]

Hi,
The B6000 is quite simple to re-wire, you will probabaly find it eisier, if you relase the dash panel from the steering column, as most of the work is behind there.
I had to sort mine out, as a previous owner had disconnected the glow indicator and wired the starter switch in reverse. I also had to replace the battery and starter cables. I also took the opertunity to wire in rear lights and a rear working light that I soldered to the spare position on the light switch.
The Japanese type bullet conectors are available from Auto electric supliers, and it realy isn't expensive to do.
I got all the parts from this online company that ship worldwide, http://www.autoelectricsupplies.co.uk/ although you may have a suplier localy.

 

[Oldie68]

As mentioned in a prior thread, my battery will hardly turn the tractor over.

I measured the voltage from positive to negative terminal with the tractor off and the tractor running at high RPM. There was no difference in voltage. Just for kicks, I took the positive terminal off, and measured the voltage while running. It was 0.3 volts.

I then unplugged the dynamo from the wiring harness, and took voltages across all three wires while running at wide open throttle. They were always been 28 to 30 volts. I understand from another forum that it should be 43 volts between brown and white and 30 between brown and yellow. Is this true or false? Is 30 volts too low between B & W? These are all AC voltage measurements.

To complicate matters, someone has rewired my machine and did not follow the wiring diagram. Tell-tale clues include the fact that no wires go to the light switch, and some amateurish type splices. It wouldn't surprise me if my charging problem is related to a bad splice.

If I don't care about having headlights or a horn, what is the simplest way to wire this tractor and make it work? I think it would be a real chore to trace all of the wires and wire it up as per factory.

Is there any way to test the rectifier?

Thank you,
Chris

Hey did you eventyally figure out your charging problems?
I too have a B6000 just acquired and am trying to figure out the chatging issue. From the poorly wtitten and informed manual it ststes that the output of the (dynamo, from what i know dynamo's produce DCcurrent not AC) is 90W. In other information stated in online forums, the output in current rating at battery should be somewhere around 13.5V-14V. With what I remember from the laws of electricity 90W÷6.5A should produce 13.5V. I have a digital and analog meter. The analog reads on the 50V setting from what I can tell somewhere in the vicinity of 13V-14V DC at battery when running, throttled up, with the digital meter on the setting it has 300V DC it reads only 11V.
My wiring is apparently intact. So I'm still in the process of figuring mine out as well.

 

[kubotasam]

The dynamo produces AC current. It is changed to DC with a rectifier located under the dash. Your dynamo should produce approximately 30 volts ac with the wires coming from it disconnected and the engine at full throttle.

 

[Oldie68]

The dynamo produces AC current. It is changed to DC with a rectifier located under the dash. Your dynamo should produce approximately 30 volts ac with the wires coming from it disconnected and the engine at full throttle.

Thankyou to all who have supplied information on this topic/my problem.
Well some solutions/remedy found. After some testing, head scratching, and thought, I observed at the headlight switch one wire detached/broken off of the headlight switch, the opposite ebd goung to a terminal on the rectifier. So I added a piece of wire and soldered it back to thd switch.
Now analog neter reads above (oscillating a bit ) 12V and at times near 14-15. Headlites appear somewhat brighter to. So I think this may have solved the charging dilemma.

 

[Dave_eng]

Does your dynamo have 2 or 3 output wires.
By answering this question a lot of useful info will be gained?
The tractors with 3 wire dynamos use AC power direct from the dynamo to power the headlights.

Dave

 

[Oldie68]

Does your dynamo have 2 or 3 output wires.
By answering this question a lot of useful info will be gained?
The tractors with 3 wire dynamos use AC power direct from the dynamo to power the headlights.

Dave

Hi Dave, on mine there are 3 wires coming from the dyamo to the wiring harness. As I reported the headlights seem brighter, but the reflective part on the rear inside of rge headlights especially on one has deteriorated with condensation and rust.
I'm hoping the headlight housings come apart, as I hope to cobble something as a refective background to nakr the lighst shine a bit better (tin foul or snall meat pie plates with a hole cut in the middle??
Whatever will work.
Lol

 

[Oldie68]

Hi Dave, on mine there are 3 wires coming from the dyamo to the wiring harness. As I reported the headlights seem brighter, but the reflective part on the rear inside of rge headlights especially on one has deteriorated with condensation and rust.
I'm hoping the headlight housings come apart, as I hope to cobble something as a refective background to make the lights shine a bit better (tin foil or small meat pie plates with a hole cut in the middle??
Whatever will work. From what I've learned particularly on mine there are two setting for the headlights (presumably low and hi beam?) also these two setting affect the rate of charge as well in conjunction with the rectifier.
Lol

 

[Dave_eng]

I have marked up the 3 wire B6000 wiring diagram in two formats. JPEG and pdf. The pdf is attached and the JPEG is immediately visible. Depending upon your computer and printer one format may print more clearly than the other.

In the box showing the circuit diagram of the Main Switch, the Starting Switch and the Light Switch the light switch box says both positions 1 & 2 are the same. One position is not brighter than the other.

The dynamo is putting out 3 phase AC voltage. One pair of these phases is used to charge the battery thru the rectifier. These are colored Purple and blue,

Another pair is putting out AC to the headlight. These are colored Yellow and Purple,

If you try replacing your existing headlights with LED's most LED's wont work on AC. A few owners have reported success with LED's but I have not seen this myself but these products are always evolving.

The headlights are not high and low beam. The headlight brightness will increase with higher engine rpm.

Dave

 

[Oldie68]

I have marked up the 3 wire B6000 wiring diagram in two formats. JPEG and pdf. The pdf is attached and the JPEG is immediately visible. Depending upon your computer and printer one format may print more clearly than the other.

View attachment 80564

In the box showing the circuit diagram of the Main Switch, the Starting Switch and the Light Switch the light switch box says both positions 1 & 2 are the same. One position is not brighter than the other.

The dynamo is putting out 3 phase AC voltage. One pair of these phases is used to charge the battery thru the rectifier. These are colored Purple and blue,

Another pair is putting out AC to the headlight. These are colored Yellow and Purple,

If you try replacing your existing headlights with LED's most LED's wont work on AC. A few owners have reported success with LED's but I have not seen this myself but these products are always evolving.

The headlights are not high and low beam. The headlight brightness will increase with higher engine rpm.

Dave

Hi and thanks very much Dave for the added info. From my recollection of the particular wire that was broken off it was the short wire highlighted in pink (which is actually red)from the headlight switch to the rectifier that was broken off hence why the charging system wasn't working. It wasn't really easy to see that it was broken as I only sort of saw it when I was looking around in behind the dash.
I want to replace that little oil pressure light, with an led as the rubber grommet it sits in isn't holding it in to where it is supposed to show on the dash.
I recall reading somewhere the 2 position switch affected the charge rate with respect to the headlights, is that correct? Something like first position of headlight switch as something like 7.5A and then the second bumped it up to whatever the full amp charge would be given all things operating as they should.

 

[Oldie68]

I have marked up the 3 wire B6000 wiring diagram in two formats. JPEG and pdf. The pdf is attached and the JPEG is immediately visible. Depending upon your computer and printer one format may print more clearly than the other.

View attachment 80564

In the box showing the circuit diagram of the Main Switch, the Starting Switch and the Light Switch the light switch box says both positions 1 & 2 are the same. One position is not brighter than the other.

The dynamo is putting out 3 phase AC voltage. One pair of these phases is used to charge the battery thru the rectifier. These are colored Purple and blue,

Another pair is putting out AC to the headlight. These are colored Yellow and Purple,

If you try replacing your existing headlights with LED's most LED's wont work on AC. A few owners have reported success with LED's but I have not seen this myself but these products are always evolving.

The headlights are not high and low beam. The headlight brightness will increase with higher engine rpm.

Dave

Hi again Dave, yes when I got the tractor I did buy some 1156 LED bulbs and they worked somewhat, can't remember if I got that flicker that some LED's are known to cause, but with the reflective part of the rear of the headlight assembly being not so good they weren't much better that the filament type. I'm going to see if the headlight assemblies come apart and maybe use some tin foil or small aluminum meat pie plates with a hole cut in the center to see if I can improve the headlight effectiveness. Not sure if I can get new replacement ones at a respectable cost.

 

[Oldie68]

Hi and thanks very much Dave for the added info. From my recollection of the particular wire that was broken off it was the short wire highlighted in pink (which is actually red)from the headlight switch to the rectifier that was broken off hence why the charging system wasn't working. It wasn't really easy to see that it was broken as I only sort of saw it when I was looking around in behind the dash.
I want to replace that little oil pressure light, with an led as the rubber grommet it sits in isn't holding it in to where it is supposed to show on the dash.
I recall reading somewhere the 2 position switch affected the charge rate with respect to the headlights, is that correct? Something like first position of headlight switch as something like 7.5A and then the second bumped it up to whatever the full amp charge would be given all things operating as they should.

Also by the way once I saw the wire broken off I viewed my wiring diagram in my manual and found that it did in fact affect the charging circuit/system.

 

[Dave_eng]

I recall reading somewhere the 2 position switch affected the charge rate with respect to the headlights, is that correct? Something like first position of headlight switch as something like 7.5A and then the second bumped it up to whatever the full amp charge would be given all things operating as they should.

I cannot say no with absolute certainty but studying the switch logic table and the wiring diagram I do not see how that could happen. I know of some motorcycles where they switch the 3 phases of their dynamo on when the headlight is on and then back to a single phase (2 wires) but their headlights run on DC.

Small B tractors made after your B6000 only have two wire dynamos and they run the headlights and charge the battery.

If I had your machine in front of me armed with a Fluke multi meter, the answers would become clear but trying to read a fuzzy wiring diagram................

Dave

 

[Oldie68]

I cannot say no with absolute certainty but studying the switch logic table and the wiring diagram I do not see how that could happen. I know of some motorcycles where they switch the 3 phases of their dynamo on when the headlight is on and then back to a single phase (2 wires) but their headlights run on DC.

Small B tractors made after your B6000 only have two wire dynamos and they run the headlights and charge the battery.

If I had your machine in front of me armed with a Fluke multi meter, the answers would become clear but trying to read a fuzzy wiring diagram................

Dave

I hear ya, well I have a few meters, a couple I can put my hands on, a cheapie tiny analog and another tad more expensice digital which only has the lowest DC volt setting of 300V, which at the battery terminals running at throttled up postion i only read 11V, but with the cheapie abalog i read above 11 volts but its sort of odcillating above 11volts upward to almost 15v on the 50 volt dc setting

 

[Dave_eng]

I am going to guess your rectifier is shot and what you are seeing at the battery posts is some AC voltage leaking through the rectifier diodes.

Forum member Lugbolt, a very smart guy, put together a diagnostic procedure covering old B dynamo's
I will attach it to this post for you to study.

I found an Operators' manual for the B6000 on Kubotabooks.com. It has a much more legible wiring diagram than the same diagram in the WSM.

In the Operators' manual is a description of the light switch operation. Maybe this DIM position is why you think there is two positions when in reality DIM and OFF might be the same.

Does your manual have a clear wiring diagram like this one attached?


Dave

 

[Oldie68]

I am going to guess your rectifier is shot and what you are seeing at the battery posts is some AC voltage leaking through the rectifier diodes.

Forum member Lugbolt, a very smart guy, put together a diagnostic procedure covering old B dynamo's
I will attach it to this post for you to study.

I found an Operators' manual for the B6000 on Kubotabooks.com. It has a much more legible wiring diagram than the same diagram in the WSM.

In the Operators' manual is a description of the light switch operation. Maybe this DIM position is why you think there is two positions when in reality DIM and OFF might be the same.

View attachment 80596
Does your manual have a clear wiring diagram like this one attached?


Dave

Hi again Dave, no i actually have 2 positions as well as off.
Regarding the rectifier being shot mayve so. I'm sure one can teoubleshoot the diodes and potentially replace them or maybe kubota might just still sell parts as this or a salvage yard which I already have located one, but is in the U.S. of course.

I am going to guess your rectifier is shot and what you are seeing at the battery posts is some AC voltage leaking through the rectifier diodes.

Forum member Lugbolt, a very smart guy, put together a diagnostic procedure covering old B dynamo's
I will attach it to this post for you to study.

I found an Operators' manual for the B6000 on Kubotabooks.com. It has a much more legible wiring diagram than the same diagram in the WSM.

In the Operators' manual is a description of the light switch operation. Maybe this DIM position is why you think there is two positions when in reality DIM and OFF might be the same.

View attachment 80596
Does your manual have a clear wiring diagram like this one attached?


Dave

Hi Dave, would AC leakage rrad on DC volt scale??

 

[Dave_eng]

The concens

Hi again Dave, no i actually have 2 positions as well as off.
Regarding the rectifier being shot mayve so. I'm sure one can teoubleshoot the diodes and potentially replace them or maybe kubota might just still sell parts as this or a salvage yard which I already have located one, but is in the U.S. of course.

Hi Dave, would AC leakage rrad on DC volt scale??

The consensus I have gained from Kubota tech's who work on these machines as a profession is it is a mistake to rely on cheap meters to do diagnostic tests.

Diodes fail in several ways. Keeping in mind the diode's main job is to block one half of an AC signal, I have seen unexpected signals when trying to determine if a battery is being charged.

If things do not make sense with voltage readings, the first thing I do is to change meter scales from DC to AC.

If I am reading AC at the battery my findings are generally there is charging system trouble.

There are forum members whose electronics knowledge is much greater than mine and they may have comments to provide.

Dave