Riding mower not charging

I have a New Holland LS55 with a 19hp Kohler Command, it hasn't charged since I bought it used. I have to change the steering sector and that required taking the battery out. When I took it out I found a red and white wire just hanging there. The white wire has a electrical connector on it that looks like it goes to a screw. The red one it missing the connector. It doesn't look big enough to go on the battery connection. The wiring comes out from what I would consider the main wiring harness under the dash of the mower. Any ideas? I'm going to the New Holland dealer tomorrow to get the steering sector and I'm going to find out if I can get a copy of the wiring diagram for this model if they have it, don't know if they will do that but it doesn't hurt to ask. I thought I would try you guys in the mean time.

The wireing diagram is needed but you need to find the volTage regulator. It is attached to the shroud and has three spade connectors. Search kohler command votage regulator to see what it looks like. The outside two wires come from the alternator and should have AC voltage on them when the engine is running. Going from memory around 26 volts. The center wire should read battery voltage. Check with enine both off and running shold be about 14 volts DC when wide open and good battery. Several times recently I have had no charge conditions where I had AC voltage and battery voltage but new regulator did not fix a no charge problem. I had to ground the regulator to the block to get them to charge. No clue as to why as they were not grounded originally and worked??

The red (+) and white (-) wire are for running 12 volt accessories (lights, PTO, aculators, aux outlets etc). The red wire should read the same voltage as the battery with the Key on.

Good luck finding an accurate wiring diagram. I have found that 90% of Kohler diagrams do not match what you are working on. You can be working on something where have the diagram for the exact model, make and serial number laid out in frotn of you and find where it shows a red wire in the diagram you may be looking at a blue one on the machine, shows a green wire going into a white on the machine when the diagram shows it should be yellow into brown.

Kohlers however are not hard to trace down. Locate the rectifier/voltage regulator. Two whites and a purple (may be faded to blue) plugged into it. The two whites come from the alternator under the flywheel. Purple is for the battery. However it takes a few detours to get there. Somewhere along the line it will change to red. The red will go into the AMP meter if equipped (small spade connector). Out out of the amp meter (larger spade connector) to a fuse holder (flat 30 amp fuse). From the fuse it will split with one leg going to the key switch the other to the battery. Your key switch may have two red wires going into it. One supplies power to the switch the other supplies power to the fuel cut off switch on the carb when the key is turned on. All of the other wires on the switch are for starting, lights and safety switches which must be open or closed (depending on type) to complete the circuit for the key to work.

Before you dig to deep into it or waste a wad of cash replacing parts or paying someone to chase wiring gremlins. Try this little test. Locate the Rectifier. Use a piece of 14/16 Ga wire. Start the engine. Hold on end of the wire to a bolt/screw that holds the rectifier to the engine. Hold the other end to a good clean ground on the frame (not the battery) and watch the Amp meter. Jumps to the full + side of the meter = Good. Shut the engine off and attach the wire permanently. Restart the engine. With a volt meter you should have at least 14 to 14.6 volts with the engine running full throttle. If so your rectifier and alternator are now communicating with one another again and your problem is solved.

Glad to see I am not the only one who has run into the regulator grounding issue. I am not good enough with electricity to know why but curious as to what goes on that causes this? First one I did had been fooled with and I figured they had not connected the ground when they replaced the engine. The other two times the tractors were unmolested originals that had quit charging and never had a ground until I installed one. Just wondering of you could explain what goes on to cause them to stop charging without the ground wire?

(quoted from post at 03:43:16 07/14/17) I am not good enough with electricity to know why but curious as to what goes on that causes this?

Just wondering of you could explain what goes on to cause them to stop charging without the ground wire?

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"Back in the day" as they say engine parts were made of metal. Being made of metal the rectifier was grounded through the mounting screws and the metal shrouds.

Fast forward a few years to when the shrouds became plastic which are not a good conductor for electricity. Kohler thought that it was a good idea to mount the rectifier to the plastic engine shroud for cooling which I agree with. Except they had forgotten (or ignored) the fact that the rectifier needed to be grounded. So thousands of engines left the factory without the rectifier being grounded.. Yes it worked for awhile and a few are still charging today. Usually tho it stops charging by the time the machine is ready for its first or second new battery. When a ground wire/strap is needed to ground the rectifier to get it charging properly again. I can not explain or even know how it ever worked without ever being grounded in the first place.

Since about 2003/4 I have been adding a ground strap to every Kohler engine that I have worked on that has a rectifier that is not grounded. And have never had one come back with a charging problem.

The rectifier that Kohler uses is not a Kohler exclusive. The same rectifier is used on thousands of different engines and machines. I have saw them used on everything from Motorcycles to race cars.

I guess it is about the same as when Kohler thought that DSAI and DSAM ignition systems were a good idea.. I will not even mess with an engine that has firing issues that has one of those ignition systems. Just go ahead and install a MDI ignition conversion kit and be done with it.

Install a ground strap to your Kohler engines non grounded rectifier and 99% of your charging systems problems are cured instantly.

All the shrouds on my lawn mower Kohler Command engine are made of metal. It was made in 2006.