Kohler 16hp questions/issues

[macallis180]

Newbie here to a AC 716H. Never had a Kohler before, never had this newer series before.

Can't seem to pick up voltage at higher rpm on 2 wires coming from under shroud (regular electrical tape wound around these, so who knows what Ihave). (Tractor doesn't have a regulator/rectifier on it, didn't have ammeter)

Didn't know any of this as bought out of state, and I was only familiar with the Briggs that I have on my B series.

$$ are mounting.  A friend has what he thinks is a good 10 amp stator he would sell me (I know this tractor would ordinarily have a 15amp), so wondering if I can find a used 10amp rectifier/regular, would I be able to make this work? Will only mow lawn with this unit, so the draw would be intermittent use of electric lift.

[rbstuartjr]

I believe you can retrofit a 15 amp stator then put in regulator / rectifier to most kohlers. I would check eBay for good used stator as that’s what I’ve done before. Some of the older kohlers originally came with a 2-3 amp unregulated charging systems.

[GWGAllisfan]

 Aren't the wires coming out of the shroud on a  K series like used in the 716 supposed to be AC (like about 25 volts), then the rectifier converts both sides to DC at just over 12 volts to ground?

I know that's how my 712 is. It has a large block rectifier, not the smaller one mounted in the shroud

[SmilinSam]

43 minutes ago, GWGAllisfan said:

 Aren't the wires coming out of the shroud on a  K series like used in the 716 supposed to be AC (like about 25 volts), then the rectifier converts both sides to DC at just over 12 volts to ground?

I know that's how my 712 is. It has a large block rectifier, not the smaller one mounted in the shroud

I think thats right. Most all the Kohler K series that use a ring gear starter have the regulator/rectifier mounted right on the engine. Older ones were a big aluminum finned one mounted to a plate that was mounted to the engine shroud. The newer ones(to this day) are a smaller black rectangular ones mounted into a matched hole right in the shroud.

Been a long time since I had a unregulated system pass through my shop, but I think those used a "half" ring stator. Magnet arrangement on the flywheel might also be different than the ones used with the other stators. Cant remember, maybe someone else knows. Seems to me that there are some different  magnet arrangements used in different Kohler charging systems. ...??...

14 hours ago, macallis180 said:

$$ are mounting. 

Before you go throwing more $$$ into it, I would pull the flywheel and check to see whats there. Make sure the magnets are all intact. Glue sometimes fails and they come off.  If that is the case, and/or if the magnet arrangements are different you will need more than just a stator  and regulator/rectifier

Best way to change a charging system is to get ahold of a blown engine with a good system and swap the whole thing into yours... flywheel, stator and regulator/rectifier. If possible  pull the flywheel before you buy it though.

[CarlH]

2 hours ago, rbstuartjr said:

I believe you can retrofit a 15 amp stator then put in regulator / rectifier to most kohlers.

If you have a flywheel with the full complement of magnets,  the current output can also be increased by upgrading both stator and rectifier/regulator to the 25 amp versions.  BTW, if you have a 15 amp stator the current output can be increased to 20 amps just by installing a 25 amp rectifier/regulator.

[macallis180]

Last evening I asked a neighbor guy that has some Kohlers to take a look at my Kohler situation.  He was able to figure out that the stator is putting out AC current. He spent a lot of time straightening out the cobbled, broken mess of wiring that I have now - put everything on long jumper wires until I get a rectifier (ordered), then will reroute and shorten up wires correctly. It was a mess.

Hopefully, may get a charging system - yay! 

Edited October 21, 2021 by macallis180
add info

[Bill725]

The 18HP Kholer in my old 7018 had a I think 3-amp charging system with a in-line diode, which is an electrical check valve, that would only allow the positive portion of the AC current to flow. There was no regulator/rectifier.

Hopefully, @BLT, who still has a 7018 can provide comment.

Edited October 21, 2021 by Bill725

[AllisChalmers716]

In the last couple pages there is a wiring diagram for the Kohler tractors.I also can get some pics of my voltage regulator with assioatted wiring. Plus it handy to have a manual                                                                                                    https://www.gardentractortalk.com/d3/downloads/monthly_11_2016/3a54dbdceb80c976e29b6cef918aa05a-6126-f9e14607-7643-41e1-9080-a1ddf68f26f7.pdf                                                                                                                                              Operators manual (with wiring diagram).

https://www.gardentractortalk.com/d3/downloads/monthly_11_2016/1da68793d813e5f746fa97f4e0a0cc42-716-1690212-parts.pdf                                                                                                                                                                                             Parts break down of its Simplicity counter part.                       

http://bsintek.basco.com/BriggsDocumentDisplay/default.aspx?filename=ifDDFO9jwJ9iGclRzOfEP5NRQpe                       Genaral large frame simplicity manual.

[CarlH]

6 hours ago, Bill725 said:

The 18HP Kholer in my old 7018 had a I think 3-amp charging system with a in-line diode, which is an electrical check valve, that would only allow the positive portion of the AC current to flow. There was no regulator/rectifier.

That inline diode is known as a half-wave rectifier in my business and that charging system has a stator/magnet setup that produces a different (likely higher) AC voltage (and lower AC current) to get the effective 12 VDC+ needed to run the lights and keep the battery charged.  The newer rectifier/regulators have 2 major components.  First, a full-wave rectifier (takes 4 diodes in a bridge configuration) to convert the AC from the stator into DC. This produces a higher net DC voltage than the half-wave rectifier for the same peak-to-peak AC voltage.  Then there is a voltage regulator stage that smooths the DC some and keeps it at a voltage level the battery can live with.  Al Eden had some really good articles about the various charging systems.

[macallis180]

Thanks, guys. 

I did order a service manual, and parts manual which I  have.  Looking at those helped my friend straighten out some of the cobbled up/broken wiring that is now on the tractor.

The "rest of the story" may be written by the end of next week when I should have the replacement reg/rectifirer.. Hope it's a good ending!