L2201 overcharging issue

[Thanasis]

Does anyone have a wiring diagram for the regulator of L2201? My battery died suddenly so I installed a voltmeter on the dashboard and realized that I was getting more than 15 Volts after 2000rpm. Any suggestions on what to check beside the regulator?

Thanks!

 

[85Hokie]

Check the grounding circuit - a poor ground will force the regulator to work "harder" because the circuit is trying to force the electrons down a path of poor conductivity.

Same is true with the wiring COMING from the VR - if one of those is nicked - chewed into, it will cause the same problem.

Then again the VR could be bad - but I would check wiring first - nice bright and tight!

 

[BruceP]

Check the grounding circuit

Agreed!

I once troubleshot an overcharging issue. Using voltmeter, I discovered the chassis voltage was ~2v higher than the battery minus terminal.

Since the regulator uses the chassis as reference.... this meant the regulated voltage was ~2v too high. (Exactly as the OP is seeing)

 

[Dave_eng]

You need to do some research but I suspect your L2201 is a Gray Market tractor if it were in North America and not Greece

. If the labels etc on the machine are written in Japanese this would confirm the GRAY status.

I recall long time forum member stating the L245 was the North American equivalent.

If your research confirms this, then Kubotabooks.com has WSM for old L series but be forewarned these manuals leave a lot to be desired.

Start on page 27.

Kubota Books

Where is your volt meter connected to?

Follow 85hokie's advice and check out all grounds and look for damaged wiring.

Dave

 

[Thanasis]

The L2201 is indeed the L245 equivalent with minor differencies. My voltmeter is connected to the battery cable on the main switch, so I can chek the battery readings while working. But I also used a multimeter hooked directly to the battery and confirmed that the readings were the same. The charging light on the dash stays dim and the readings on the battery continue to rise far beyond the normal depending on the motors revs. I will start testing and let you know.

Thanks again!

 

[BruceP]

The charging light on the dash stays dim

This is a clue. That light can only go out if both leads are at same potential. A dim light suggests there is a voltage differential.

One troubleshooting approach would be to start at that bulb with meter to get some numbers. (Always referenced to negative battery terminal...NOT the connector)

Another approach would be 'voltage differential' measurements.

 

[Thanasis]

So I started with the alternator test as the wsm suggests. The readings are all ok except from the resistance which about 0,5Ohm less. This is likely due to the poor state of the connectors. Anyway I continued with regulator test. First test was ok (around 4,9 volts) but during the second I got the same readings that I already mentioned. What I noticed is a poor state and corrosion on the alternator cable connector. Additionally I opened the alternator itself as the test suggests to adjust the metal connector inside. What I saw there is a little bit of dirt-corrosion, I am not sure, while on the first relay ( where I got the normal results) the contacts look like new. Anyway I will change all regulator cable connections and run the test again. I hope it will something simple like that and avoid spending money for a regulator.
I also seen new alternators with the regulator within but this is even more money and new cable lines.

I will update the post soon! Thank you all!

 

[Thanasis]

So I started with the alternator test as the wsm suggests. The readings are all ok except from the resistance which about 0,5Ohm less. This is likely due to the poor state of the connectors. Anyway I continued with regulator test. First test was ok (around 4,9 volts) but during the second I got the same readings that I already mentioned. What I noticed is a poor state and corrosion on the alternator cable connector. Additionally I opened the alternator itself as the test suggests to adjust the metal connector inside. What I saw there is a little bit of dirt-corrosion, I am not sure, while on the first relay ( where I got the normal results) the contacts look like new. Anyway I will change all regulator cable connections and run the test again. I hope it will something simple like that and avoid spending money for a regulator.
I also seen new alternators with the regulator within but this is even more money and new cable lines.

I will update the post soon! Thank you all!

Minor update

The B line (battery) from the regulator to main switch was cut. When I reconnect it the light on the dash no longer dims but the battery is not charging. When I take it off like it was before I get again the non stop overcharging issue. Ground cable is fine. Any suggestions? Should I try a new regulator?

 

[Thanasis]

Hallo everyone,

the problem was actually the regulator. I just installed a new one and now at 2000rpm it is constantly at 14,4 volts! I used a new type of regulator equal to the nippondenso it had originally, for almost 1/4 of the nippondenso price.
Thank you all for the advice!

 

[Dave_eng]

Hallo everyone,

the problem was actually the regulator. I just installed a new one and now at 2000rpm it is constantly at 14,4 volts! I used a new type of regulator equal to the nippondenso it had originally, for almost 1/4 of the nippondenso price.
Thank you all for the advice!

Could you please post details on the regulator you bought. It will certainly help someone in the future.

Dave

 

[Thanasis]

Could you please post details on the regulator you bought. It will certainly help someone in the future.

Dave

After a lot of search for an equal alternator I ordered the Hitachi or Huco 132801. Same socket for the cables with an extra 12volt cable to use it for something else. Price in Greece 32 euros with shipping while the price for the Nippondenso 026000-2121 is 120€.

 

[Dave_eng]

After a lot of search for an equal alternator I ordered the Hitachi or Huco 132801. Same socket for the cables with an extra 12volt cable to use it for something else. Price in Greece 32 euros with shipping while the price for the Nippondenso 026000-2121 is 120€.

The extra alternator cable is used for an electronic tachometer

Dave