Scag / Kawaski Not Charging

LSU-Mike

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Joined
Jun 10, 2019
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The battery on my Scag Freedom Z isn't charging. It has a Kawasaki FH580V. My initial diagnosis a few days ago indicated the rectifier was bad. The AC voltage from the stator was over 24V (and still is). I read only battery voltage between the rectifier terminal going to the battery, not 14 or so as expected. "Assuming" the rectifier was defective I ordered a replacement. I chose to order one from source "A" for $23 instead of a factory replacement at $83.

While I was waiting for the replacement to arrive I charged the battery. The replacement physically appeared identital to the original, so I plugged it in. The mower started quickly. In my rush to catch up on grass cutting, I didn't measure the "charging" voltage to the battery. Everything was fine for a few days, but I began to recognize that startup began to slow down. As with the defective rectifier, I wasn't getting 14+VDC to the battery. Still getting 24+VAC from the stator.

The photo below is the replacement. I don't know what the marking on the terminals are supposed to mean. There are no terminal markings on the original rectifier. Below are the ohm readings for the replacement.
With positive meter lead first on 1, then 2:
1 to 2 - 2.8M Ω
2 to 3 - 0 Ω
With negative meter lead first on 1, then 2:
1 to 2 - ∞
2 to 3 - 0 Ω

The wire for charging the battery is on terminal 3 as it was for the original rectifier. On the original rectifier terminals 2 and 3 are joined together.

Do I have the correct replacement? Is it defective? Do I have some other issue? The fuse in the charging circuit is OK.

Thanks
Mike
Rectifier.jpg
 

ILENGINE

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10,032
Stator voltage too low. Need at least 28v AC at the stator to produce 14v DC for the battery Service manual calls for 28.4 AC for standard output with 26 being the minumum
 

Hammermechanicman

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Joined
Jan 10, 2020
Threads
56
Messages
3,528
The battery on my Scag Freedom Z isn't charging. It has a Kawasaki FH580V. My initial diagnosis a few days ago indicated the rectifier was bad. The AC voltage from the stator was over 24V (and still is). I read only battery voltage between the rectifier terminal going to the battery, not 14 or so as expected. "Assuming" the rectifier was defective I ordered a replacement. I chose to order one from source "A" for $23 instead of a factory replacement at $83.

While I was waiting for the replacement to arrive I charged the battery. The replacement physically appeared identital to the original, so I plugged it in. The mower started quickly. In my rush to catch up on grass cutting, I didn't measure the "charging" voltage to the battery. Everything was fine for a few days, but I began to recognize that startup began to slow down. As with the defective rectifier, I wasn't getting 14+VDC to the battery. Still getting 24+VAC from the stator.

The photo below is the replacement. I don't know what the marking on the terminals are supposed to mean. There are no terminal markings on the original rectifier. Below are the ohm readings for the replacement.
With positive meter lead first on 1, then 2:
1 to 2 - 2.8M Ω
2 to 3 - 0 Ω
With negative meter lead first on 1, then 2:
1 to 2 - ∞
2 to 3 - 0 Ω

The wire for charging the battery is on terminal 3 as it was for the original rectifier. On the original rectifier terminals 2 and 3 are joined together.

Do I have the correct replacement? Is it defective? Do I have some other issue? The fuse in the charging circuit is OK.

Thanks
Mike
View attachment 66040
Stator wires connect to 1 and 3 and battery connects to 2 and case of regulator must be grounded.
 

StarTech

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Feb 19, 2020
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Stator varies so it must tested at 3000 rpm. At this rpm the minimum output is 26 vac.

As for testing the voltage with a ohm meter use the following chart.
1690310135540.png
 
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