1975 C-120 Automatic

[timmy b 10]

I own a 1975 C-120 Automatic with a K301 engine that runs great.  Recently I've had a couple of dead battery issues.  I've replaced the battery and all seems fine however I am now curious to know what exactly it is that keeps the battery charged while the tractor is running and in use.  I've looked at some material and read that the "regulator" plays some part but I'm wondering if their is more?  I've not been on the site for a while but I figured this might be a good place to ask.

 

Thanks 

Tim

[Achto 26,566]

11 hours ago, timmy b said:

"regulator" plays some part but I'm wondering if their is more?

 

A stator behind behind the fly wheel produces AC voltage while the engine is running. Your regulator / rectifier turns this into DC voltage and regulates the charging of your battery.

 

How to test your charging sys. Unplug the regulator. Start the engine, while the engine is running you should have about 24 to 30 volts AC between the outside terminals of the plug. Most times you will find that this will check out, turn the engine off. Make sure that the body of the regulator is grounded well. Plug it back in and test the voltage at the battery. While the engine is running you should have around 14 volts DC at the battery. If this part does not check out then you most likely need to replace your regulator / rectifier.

Edited April 2, 2019 by Achto

[timmy b 10]

Thank you, great answer!  I'll want to do your suggested tests but I'm going to need to gear up...I've done lots of things but wiring and "electrical systems" are a weakness...even the basics.  Is there any "down and dirty" way to know if the battery is changing while running?  And one more question...is there any likelihood of the stator going bad?

Thank you again,

Tim

[oldredrider 2,547]

Down and dirty answer. Check battery voltage without engine running. Start the engine and check again. If voltage increases, it is charging. Conversely, if it is lower, not charging.

[timmy b 10]

Sounds like something I can handle... Thank you!

[Achto 26,566]

20 minutes ago, timmy b said:

I've done lots of things but wiring and "electrical systems" are a weakness...even the basics.

 

If you have a Harbor Freight in your area, this is a valuable tool for about as cheap of a price as your gonna find.

https://www.harborfreight.com/7-function-digital-multimeter-63604.html

 

[timmy b 10]

Perfect..thanks!

[timmy b 10]

This is a pretty amazing website when you can ask an electrical question about a 45 year old red tractor and essentially have your answer within 3 hours by owner/experts.

Very cool!

Thanks guys,

Tim

[Achto 26,566]

9 hours ago, timmy b said:

And one more question...is there any likelihood of the stator going bad?

 

Sorry I missed this question. There may be a slight chance that the stator is bad, but this is normally not the issue. It is much more likely to have bad connections, broken wires or a bad regulator/rectifier

Edited April 2, 2019 by Achto

[timmy b 10]

On 4/2/2019 at 7:21 AM, Achto said:

 

Sorry I missed this question. There may be a slight chance that the stator is bad, but this is normally not the issue. It is much more likely to have bad connections, broken wires or a bad regulator/rectifier

 

 

Thank you Achto...I knew you were going to get to that one sooner or later .  I was hoping/expecting that was the case with the stator...I figured you guys would have emphasized it more if necessary.  I did the D&D test and it clearly appears as though the battery is receiving a charge while the C is running.  You guys have been very helpful...thanks again!

[timmy b 10]

One last thing...if I posted an engine operation question/problem regarding my 1996 314-8 Automatic would you be fielding it in that particular Red Square section?  

[Achto 26,566]

52 minutes ago, timmy b said:

if I posted an engine operation question/problem regarding my 1996 314-8 Automatic would you be fielding it in that particular Red Square section? 

 

I would post the question in the engines section.