Scag Turf Tiger battery not charging

[VegetiveSteam]

It is possible I’m not getting ground. I’ll have to double check when I get back.

Until you get battery voltage to the regulator/rectifier ground makes no difference. Once you get battery voltage to the regulator/rectifier, take your voltmeter, ground the black lead and touch the red lead to the metal part of the case of the regulator/rectifier. If you read voltage through the case, you know you have a ground problem. If there is no voltage apparent at the case, the ground is fine.

 

[JW 1]

You need to figure out why the DC wire shows no voltage. It should always at least show battery voltage. Right now, you have no connection to the battery, and you can't charge a battery you're not connected to. The violet-colored wire runs from the B+ terminal of the regulator/rectifier directly to the same post on the starter solenoid that the positive battery cable connects to. That is it's connection to the battery. That violet wire has a 30-amp fuse in it that could be blown, or it could just be a bad connection. Either way, it's a fairly short wire with a fuse holder in it and could easily be replaced if need be.

Ok. Just curious but if the ground wire wasn’t grounded would that effect battery voltage from showing on the DC wire? I’m almost sure that the wires at the starter are connected correctly.

 

[VegetiveSteam]

Ok. Just curious but if the ground wire wasn’t grounded would that effect battery voltage from showing on the DC wire? I’m almost sure that the wires at the starter are connected correctly.

The suspected bad ground would be if the regulator/rectifier is grounded. That would have no effect on DC voltage on the B+ wire.

 

[VegetiveSteam]

I guess to clarify, when you are checking for voltage at the B+ wire, where are you grounding the black lead of your meter? If you’re trying to ground it using the metal case of the regulator, then yes, a bad regulator ground could cause you to see no voltage on that wire. I always try to use the negative terminal of the battery as my ground. That’s your best ground.

 

[JW 1]

I tried the negative and the positive. The negative didn’t show any reading. I will update you when I get back tonight.

 

[JW 1]

Well I feel stupid! It turns out that I missed a fuse. 30amp near the starter. I guess my eye sight isn’t as good as I thought!

I would like to thank everyone for the excellent advice!

 

[VegetiveSteam]

Glad it wasn't anything more serious. Thanks for sharing what you found.

 

[Freddie21]

Here's the IPL with wiring diagrams.

https://www.scag.com/wp-content/uploads/2020/04/STT_IPL_Book_06277.pdf

 

[VRR.DYNDNS>BIZ]

At some point up front you mentioned a new engine. There can be a chassis to engine variation in harness parts and a need to get an adapter so each wire in that bulk connector is proper.

 

[jviews12]

This may help, or confuse the issue. Once engine is running, do you get AC voltage from AC wires? Then do you get DC voltage from DC wires? I agree ground is suspicious and needs be confirmed. I would charge the battery. Measure battery voltage before starting engine and record it. I would then start engine and record voltage again. If voltage at battery when running is not same or less than DC leads from regulator, yes it is a wire issue which needs be traced to where it stops being present. Hopes this helps. (2 cents) why did you change the regulator? Was this because of charging issue and maybe the old one was good and this is really a wire issue and the new component was not needed? I am concerned you replaced before measuring outputs of old stator/regulator.