B8200D Voltage Regulator Wiring

[bkboggy]

Hey, folks. I'm trying to get my B8200D working. It's rusted all over the place, leaking in a few spots, and most of its electrical system was chewed up by rats (on top of bunch of patch jobs over the years before I got it). So, I set out to completely rewire it as one of the first steps.

Problem is that a lot of the wiring was in horrible shape and some parts were missing completely . I was able to get some of it working. From the schematic.jpg attached to this post you may see what's been done (colored areas indicate completed portions) -- the only things I left out are: hazard unit, hazard lamp switch and all of the rear lights (my tractor doesn't have a fuel gauge, so that's left out as well).

I'm able to start the tractor and confirmed that the battery is charging from the dynamo, but I'm running into a few issues:
1. Headlights won't turn on (less important for me at the moment).
2. CHG and OIL lights are on as soon as I connect the battery -- not even putting key in (pretty important to get this fixed).

So, it appears I messed up something with either wiring up those lights or there is another issue. One area that confused me was the voltage regulator.

Per the diagram (see schematic.jpg or regulator_schematic.png), going to the voltage regulator we have:
1 green wire
2 grey wires (I used pink, based on what I had)
1 red wire
1 black wire
1 white wire (I used red here as well)

On the regulator side, we have:
1 green wire
2 grey wires
1 red wire
1 black wire (ground that gets attached to one of the bolts on the regulator)
1 yellow wire

Does white wire (red in my case) get connected to the yellow wire? Does anyone have a B8200 and care to share a picture of those connectors and their wiring?

 

[Russell King]

I don’t think that the connections at the regulator pass straight through like I think you did.

Do you have both sides of the connector to the regulator? Then you can tell what is in and out with an ohm meter.

The power to the oil pressure and voltage lamps is obviously bypassing the key switch and needs to be fed to the key switch ( probably already is) then come off the on terminal of the key switch.

 

[Russell King]

Since Kubota (and you) did not indicate where wires jump over each other (half circle) or connect to each other (dots) it can get a bit confusing. You may want to sketch just the supply (positive) side to the key switch and then to fuses then to switches or regulator.

You may need to ground the light housing to the battery to see if that resolves that

 

[BruceP]

CHG and OIL lights are on as soon as I connect the battery

It is EXPECTED to have an OIL pressure and CHARGE light as soon as the key is turned on (before starting engine)
Hence, it sounds as if the key is in the ON position.... or at least the wiring is powering the system at all times.

 

[bkboggy]

@Russell King

Do you have both sides of the connector to the regulator? Then you can tell what is in and out with an ohm meter.

The original one or the one I installed? I don't have the original. Could you explain how I can test the new one?

Since Kubota (and you) did not indicate where wires jump over each other (half circle) or connect to each other (dots) it can get a bit confusing.

Actually, Kubota did indicate it with solid dots on their diagram. It's easier to see in person, with me coloring over the lines. I'll update that image in a bit, so it's a bit more clear.

@BruceP

It is EXPECTED to have an OIL pressure and CHARGE light as soon as the key is turned on (before starting engine)

Right. I see them on without even having the key in the ignition.

Hence, it sounds as if the key is in the ON position.... or at least the wiring is powering the system at all times.

Right, I think the issue is with my wiring. If someone has a picture of their connectors for that regulator, it would help me figuring out the issue.

 

[Russell King]

I meant the original one but will recant the comment. Look right above the connector in the schematic and there is a diagram of the connector showing the end view of the connector with a color matching the wire colors so I am pretty sure that the wiring just does pass through the connector.

 

[bkboggy]

@Russell King Yes, but that diagram shows the harness side of the connector. On the regulator side, there is no white wire. So, does the white wire connect to the yellow one? That's the way I have it, but it may not be correct.

I treated it as passthrough and connected all of the matching colors, besides that white and yellow, which do not match in color, but they're the only ones left.

 

[bkboggy]

Here's the original diagram:

 

[bkboggy]

Here's my version (with all of the connectors, whatever you see on one side, aligns with what you see on the other side -- I don't have any of the original connectors, so I used my own):

 

[bkboggy]

@Russell King It should be easier to see those junctions in the two diagrams I uploaded.

 

[GreensvilleJay]

I suspect the original wiring diagram is wrong.
if you follow the power for the oil light..
battery +12v ->fusible link->10A fuse->light->sensor->ground
oil sensor is normally closed with engine off, so light comes on as soon as battery is connected !
Power for that 10A fuse should be from the switch.
It'd be worthwhile to google 'b8200d wiring diagram' and see if there is a correct diagram.

 

[bkboggy]

@GreensvilleJay That's the only one I've come across (this is straight from Kubota), but you do make a good point regarding the diagram being possibly wrong.

 

[bkboggy]

@GreensvilleJay I definitely think you're onto something there. I found a B7200 diagram, which is very similar, except for the fact that it shows the oil light on the 15A circuit, going through the ignition switch:

While the B8200 diagram, shows it on the 10A circuit, going through the battery:

 

[bkboggy]

Maybe the original B8200 diagram is correct, but the scanned copy that's floating around has been altered?
The junction dot that's shown on that 10A circuit looks a bit smaller than the existing ones and then there are these two spots that look like they've been rubbed off?