Need new voltage regulator.. S/G Belt

[FLtractor 205]

Afternoon,

Took my 856 K181 starter gen off tractor to local shop.. they tested it Said it works good and ran a belt on the pulley.. said will crank tractor long as battery charged. But it is not charging so need new voltage regulator Current regulator has 3 terminals front and underneath wire.. can’t find anything online based on the housing #”s. 
Also should get new S/G belt. Here is current belt and belt from Napa that supposedly fits. 

Edited Thursday at 06:01 PM by FLtractor

[953 nut 68,915]

Kohler 7hp, 8hp                                                      Kohler # 231605                                     3L-32   Notched raw rubber edges NAPA 25-7315

 

A fabric covered belt like that will not grip enough to start your engine.

[FLtractor 205]

23 minutes ago, 953 nut said:

Kohler 7hp, 8hp                                                      Kohler # 231605                                     3L-32   Notched raw rubber edges NAPA 25-7315

 

A fabric covered belt like that will not grip enough to start your engine.

Thank you for belt #. Interesting the # on Napa is a cogged belt unlike what’s on my tractor now.
regarding the Voltage regulator.. do you happen to know of a solar charger i could hook battery to if i decided not to get new voltage regulator?

Edited Thursday at 06:31 PM by FLtractor

[ri702bill 12,936]

Agreed - you need the raw sided cogged belt. It fits tighter on the S/G pulley and does not slip.

Did you attempt to diagnose your old Delco Remy Regulator? They are pretty simple...

[FLtractor 205]

25 minutes ago, ri702bill said:

Agreed - you need the raw sided cogged belt. It fits tighter on the S/G pulley and does not slip.

Did you attempt to diagnose your old Delco Remy Regulator? They are pretty simple...

Good to know about belt. Didn’t not attempt diagnosing regulator.. not sure how to do so or what to look for.. have link to good video by chance ?

Edited Thursday at 07:17 PM by FLtractor

[ri702bill 12,936]

1 hour ago, FLtractor said:

have link to good video by chance

Ha - that's funny. No - the info I have goes waaaay back. These files are a lot of knowledge, even with the corny illistrations. Remember that the origin of S/G systems dates back to the 1930's - almost 100 years ago.

 

 

Delco_Kohler_4-72_SM_Section_07.1-7.6_Starter_-_generator_HR.pdf Delco Remy Regulator Manual 1R-116.pdf delco_remy_regulator_service 1R-111.pdf

[953 nut 68,915]

Check this video out, better than most.

https://www.youtube.com/watch?v=W8C26XOFAhM

 

[adsm08 5,073]

The regulators rarely actually go bad or break, unless they were hooked up wrong, or were exposed to an electrical fault. These are old designs, from the days when things were meant to be worked on. They can be cleaned and adjusted and brought back to life as they wear.

 

If you remove the top cover and hold the unit right-side up with the three posts facing you the set of contacts responsible for charging will be to your right. Cleaning them with some fine sand paper and making sure all the other connections are good an clean, and the wires are in good shape, is likely all that is needed.

 

There is a website where high-quality regulators can be purchased still. Of course I can never remember what it is. @ebinmaine Eric, is it you that always has to remind me of that site?

[ebinmaine 80,485]

6 minutes ago, adsm08 said:

There is a website where high-quality regulators can be purchased still. Of course I can never remember what it is. @ebinmaine Eric, is it you that always has to remind me of that site?

 

 

Ain't me. Mebbe @Achto or @WHX?? knows?

[adsm08 5,073]

47 minutes ago, ebinmaine said:

 

 

Ain't me. Mebbe @Achto or @WHX?? knows?

 

Not me. I can't remember it, and I can't remember who normally, and I am still dealing with some after-effects of that head shot I took last Friday.

[Achto 32,560]

Give this regulator a try.

https://www.amazon.com/Parts-Player-12V-Regulator-1959-1966/dp/B07Z9LQJDG/ref=sr_1_25

[Handy Don 17,392]

19 hours ago, FLtractor said:

Didn’t not attempt diagnosing regulator.

If you decide to replace, please don’t discard the original--someone here would likely take it to attempt a refurb. 

[squonk 48,010]

Things would work better with the rust cleaned off the connections! 

[adsm08 5,073]

4 minutes ago, squonk said:

Things would work better with the rust cleaned off the connections! 

 

You are right, but if you look at the OP's full body of work on the forum you will notice a pattern that points towards three things.

 

1) He likely does have ADHD.

2) He likely does NOT have any Ritalin.

3) He would rather load up the parts cannon than slow down and diagnose something.

Edited 8 hours ago by adsm08

[WHX?? 57,956]

On 9/24/2026 at 7:17 PM, ebinmaine said:

 

 

Ain't me. Mebbe @Achto or @WHX?? knows?

 

Around here the farm & barn & man malls sometimes have them but watch for the 6 volt offerings. I had bought one in the jungle Dan had posted but still didn't get it to charge right. May have had other issues tho and never did get to the bottom of it. 

 

6 minutes ago, squonk said:

Things would work better with the rust cleaned off the connections! 

 

[adsm08 5,073]

On 9/25/2026 at 11:01 AM, Handy Don said:

If you decide to replace, please don’t discard the original--someone here would likely take it to attempt a refurb. 

 

Yeah, me. I have three on my work bench that I damaged making bad connections that I have since repaired.

 

Depending on what breaks I'm getting pretty good at it. About all I can't do is re-wind the magnet coils at this point.