Battery not charging

[1973Auto 80]

I have a Koehler cougar 18, on my orange tractor. In the spring thought I needed a new battery. Put that in and did not turnover just clicked. Put a new starter on. Seemed to do the trick, started mowed, success! Well every time I used it it turned over hard, like the battery is getting weaker. Only used it 7-8 times just to mow paths to my tree stand. Now yesterday started hard barley turned over but it started, let it run for good 20 minutes to charge battery, shut off then barley turned over then click😠😡. Checked the ground no rust nice and tight, so I am wondering what do I have to replace to have the battery keep charging. Thanks all!

[lynnmor 7,707]

First thing, get that battery on a charger, letting it sit in a discharged state will drastically reduce its life.  After the battery is charged, put a voltmeter across the terminals and see if you are getting more than 13 volts with the engine running.  I think that you will find lower voltage and the charging system has failed.  Download the Demystification Guide and look at the diagram for your model.  You need to tell us the model number of the tractor for more help.

[Achto 29,229]

Check the AC output of the two wires on the out side terminals of your voltage regulator/rectifier. You should have around 30 volts AC when the engine is running 1/2 throttle or faster.

 

Make sure that the body of your reg/rec is grounded well. 

 

If the above 2 things check out, then you should have around 14 volts DC at your battery or the center wire on your reg/rec.

 

If you have good AC output but can not get the correct DC voltage at the battery then I would suspect a bad voltage regulator/rectifier.

[gwest_ca-(File Mod) 11,389]

One more test.

Turn the key to the RUN position with the engine NOT running.

Check the voltage across the battery terminals.

Now move the red test lead to the regulator DC+ terminal.

You should have the same reading.

If not there is a problem with the path the charge voltage takes to get to the battery.

[Gregor 4,847]

10 hours ago, 1973Auto said:

I have a Koehler cougar 18, on my orange tractor.

You don't give a guy much to go on. Any #'s on that engine such as these?

 Many Kohler service manuals are available on line for free download. These manuals include how to test different charging systems, but first, you have to know what you have.

[953 nut 59,238]

It wouldn't hurt to have the new battery load tested but it sounds to me like you have some poor connections in your electrical system.

Remove both of the battery cables at both ends and clean them and the surface they attach to, do the same for the cable from the solenoid to the starter. A poor connection can cause a big voltage drop.

Use a volt meter to see what the battery voltage is at rest and what it is with the engine running at 2/3 throttle, any change?

 

[1973Auto 80]

48 minutes ago, Gregor said:

You don't give a guy much to go on. Any #'s on that engine such as these?

 Many Kohler service manuals are available on line for free download. These manuals include how to test different charging systems, but first, you have to know what you have.

thanks! it is a SV540.

[Gregor 4,847]

You can download the service manual from here.

https://www.kohler-engine-parts.opeengines.com/index.php?main_page=document_general_info&products_id=34596

 

I can tell you now, it basically says what has already been said above, but sometimes it's still nice to have a manual.

[gwest_ca-(File Mod) 11,389]

 

[1973Auto 80]

Thank you everyone for the feed back and manuals!!

[gwest_ca-(File Mod) 11,389]

On 9/29/2021 at 12:09 PM, 1973Auto said:

Thank you everyone for the feed back and manuals!!

Have a question for you.

Have been adding color to the wiring diagrams and notice a mistake. If you can see the back of the ignition switch can you tell us if there is a white wire or a purple wire going to the switch.

It starts out white at A2 and ends up purple so one of them is wrong.