Hello, I'm having a problem with my Kubota B6000. It's not charging any current at the battery terminals. I've disassembled the dynamo and cleaned the magnet. Now I don't know how to check if it's working properly and can use a multimeter to check the three wires. I put a light bulb between them and it turned on, but I'm not sure if it's enough. If I can't fix it, I may have to buy another one. If you know of a purchase link in Spain, I'd appreciate it. It has corrosion. I've attached a photo. P.S.: In the photo, you can also see the block with signs of corrosion. There's a large duct on the left and a small one on the right. I don't know if this is the case or if it's clogged. Thanks for your help.
Kubota B6000 charging problem
- Thread starter Jesús
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85Hokie
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To check your dyno - If you have it off, place in a vise and use a drill and socket to spin it, otherwise place on the belt and have the wires in hand and start.
PLACE your meter on AC volts - NOT DC - and let her spin.
AS for the wires - I do not remember the colors of each, but taking any two will get a voltage - or not,
you should read somewhere above 30 volts AC ...... if this checks out, then your rectifier is suspect.
PLACE your meter on AC volts - NOT DC - and let her spin.
AS for the wires - I do not remember the colors of each, but taking any two will get a voltage - or not,
you should read somewhere above 30 volts AC ...... if this checks out, then your rectifier is suspect.
85Hokie
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no...that would be bad. TYPICALLY dynos are bullet proof - did you try combos of the wires?
Russell King
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85Hokie
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I am guessing here , but the pulley on the crank is a bit bigger than the dyno pulley - so at high idle I would say 2500 rpms would be a good test rpm. Just a guess
GreensvilleJay
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To properly test, you'd need a 'burden' resistor to simulate a 'load'.
Say you want 5 amps at 14 volts, you need a 14 v / 5 a = 2.8 ohms resistor rated for 70 watts. In this case I'd use a 3 ohm, 100 watt resistor.
Unburdened the voltage will be higher......
Say you want 5 amps at 14 volts, you need a 14 v / 5 a = 2.8 ohms resistor rated for 70 watts. In this case I'd use a 3 ohm, 100 watt resistor.
Unburdened the voltage will be higher......
Russell King
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I think since it is corrodEd on that water connection point, AND it is not charging you might be better off replacing it if you can find one.
@Mountainman runs this salvage yard and I think I have seen statements that he ships worldwide. I think you may be able to get one from the Kubota dealer in Spain or Europe but no idea who
Mossy Creek Outdoors - Largest Kubota B and BX Salvage Yard in the US
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Thank you sir. I do ship worldwide but unfortunately don't have a b6000 dynamo right now. Hard to come by these days
Russell King
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Ok thank you for replying to this!
@Jesús I guess you should try to locate it elswhere or maybe build that corroded section back up or just use the casting as is, if the hose can still be attached in a working manner
Hello again, friends. I just reinstalled the dynamo on my Kubota, and at idle, it's 11.4 volts (low idle, not at all accelerated). Where could the problem be? Based on this, I only want to know if the current output is good. Therefore, I should look for a faulty regulator or some other component.
Typically the regulator is the issue and not the dynamo. Lookup kubotabooks.com and download the manual for b7100d (not new style b7100hst) as it has the 3 wire dynamo and should be the same for testing the AC output of the dynamo wires. If thats good then most likely your regulator or wiring
GreensvilleJay
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maybe under the dash ? small aluminum box with 'fins' and a5 or 6 pole connection on it. It needs to have a GOOD ground for it to work. BTW it's actually a 'rectifier-regulator'. Converting AC from the dynamo into a 'regulated' DC voltage that recharges the battery and powers lights, etc.
AS it's '3 wire', I think it's 2 windings 'low charge, high charge'. Again, GREAT wiring is required. Any corrosion, bad connections greatly affects how the charging system works.
AS it's '3 wire', I think it's 2 windings 'low charge, high charge'. Again, GREAT wiring is required. Any corrosion, bad connections greatly affects how the charging system works.
Could it be this box? I'd like to know how to check if it's in good condition, and if not, throw in the towel and take it to a specialized electrical workshop. The cables don't look very good, some are loose, I've relocated them, but I'm not sure exactly where I should have put them. Connections made that way... I don't know what you advise... I'm already losing my way with this.
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GreensvilleJay
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BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
wow that's neat !! late 60's 'tech' !! 2 TO-66case(?) power diodes by the look of it. A LOT of corrosion that needs to be addressed. Looks like the cases of the diode are NOT supposed to be grounded( touching the case) so a real good cleaning is in order along with checking with ohmmeter.
copied and zooomed up the photos. Still neat !!! Simple full wave bridge rectifer.. NO regulation. Actually just 4 'press fit' diodes, 2 into the case, other two into ISOLATED mounts. In the 1st picture the 'studs' upper left and center bottom go to the dynamo AC wires, the center right is the +12 output to battery. Actually it'd be enjoyable to take apart and refurbish, check the diodes. Old skool....NO computer !!!
copied and zooomed up the photos. Still neat !!! Simple full wave bridge rectifer.. NO regulation. Actually just 4 'press fit' diodes, 2 into the case, other two into ISOLATED mounts. In the 1st picture the 'studs' upper left and center bottom go to the dynamo AC wires, the center right is the +12 output to battery. Actually it'd be enjoyable to take apart and refurbish, check the diodes. Old skool....NO computer !!!
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Here's the wiring diagram for the B6000 and a picture of what it looked like on my one that had the wiring in ok condition. I'm not sure of what the underside of it should look like or how to test it though. I'd start with putting it back in and cleaning the terminals/rings on the wires that attach to it and see if it makes a difference.
