18 HP B&S Charging System

[Richard Milhous]

I'm curious under what conditions the 28 and 14V were measured - with or without any load connected? Did you try taking an AC reading downstream from the diode?

 

[slomo]

Must be using the wrong site then because that engine does exist on Power Portal. Keep looking.
View attachment 58354
or use this link https://www.jackssmallengines.com/j...699999-series/422400-to-422499/422447-1216-01

You have dealer access, I don't. I use the Briggs engine info site below.

Find Manual & Parts List | Briggs & Stratton

Whether you are putting your equipment away for the season or needing to replace a part, locate your equipment or engine manual to get the information specific to your product.

www.briggsandstratton.com

 

[GoHardrGoHome]

Must be using the wrong site then because that engine does exist on Power Portal. Keep looking.
View attachment 58354
or use this link https://www.jackssmallengines.com/j...699999-series/422400-to-422499/422447-1216-01

I included all the numbers in the original post.

 

[slomo]

I included all the numbers in the original post.

Confirmed but the Briggs site I use didn't pull it up. StarTech has a cool dealer power portal site he uses.

 

[GoHardrGoHome]

I'm curious under what conditions the 28 and 14V were measured - with or without any load connected? Did you try taking an AC reading downstream from the diode?

I had the wire disconnected before the diode and measured the stator's output at 28VAC. When I reconnected it and test at the battery for DC voltage, I was getting about 14.2 VDC. Now that the diode is not functioning properly and likely shorted my battery out, the DC voltage at the battery goes from 3 to, I think it was 18 VDC! I need to rectify the voltage before I get a new battery!

 

[Richard Milhous]

The battery might still be good. I'm more interested in figuring out what the multimeter is actually measuring, honestly. If the open-circuit stator is pumping 28V sinusoidal AC and the battery is fully charged, diode functional, the RMS voltage at the battery should be about 22V (assuming this is a single-winding stator with no parts other than the coils).

To solve your problem (without knowing anything about this charging system!) my advice is: Make sure there isn't supposed to be a capacitor somewhere in it. Use a diode with at least 45V rating and as much current rating as you can find. Avoid running the machine with a bad diode, or you could damage something that ain't damaged yet.

 

[bertsmobile1]

Just to get a handle on your problem
1) have you owned this mower from new ?
2) is this the original engine ?
3) Dose the mower have an electric clutch ?
a single wire diode will not be able to keep up with the power requirements of an electric clutch and recharge the battery
It will overheat & burn out .
The stators that have a single wire with diode are only for recharging the battery , usually on a walk behind mower

 

[slomo]

At minimum, use a double rated or more, amperage diode than what the charging coil puts out.

Charging coil puts out 6 amps for example. Diode needs to be 12 to 50 amp rated. Most have 2 diodes to share the amperage load I think. If you have 2 diodes in there, they should be wired in parallel or installed next to each other so to say.

 

[GoHardrGoHome]

Just to get a handle on your problem
1) have you owned this mower from new ?
2) is this the original engine ?
3) Dose the mower have an electric clutch ?
a single wire diode will not be able to keep up with the power requirements of an electric clutch and recharge the battery
It will overheat & burn out .
The stators that have a single wire with diode are only for recharging the battery , usually on a walk behind mower

I've had this mower for 17 years! I purchased it used. Everything looked to be stock, including the engine. Yes, the mower utilizes an electric clutch. It worked fine for many years with the single-wire stator and diode until the diode was damaged physically.

 

[GoHardrGoHome]

The battery might still be good. I'm more interested in figuring out what the multimeter is actually measuring, honestly. If the open-circuit stator is pumping 28V sinusoidal AC and the battery is fully charged, diode functional, the RMS voltage at the battery should be about 22V (assuming this is a single-winding stator with no parts other than the coils).

To solve your problem (without knowing anything about this charging system!) my advice is: Make sure there isn't supposed to be a capacitor somewhere in it. Use a diode with at least 45V rating and as much current rating as you can find. Avoid running the machine with a bad diode, or you could damage something that ain't damaged yet.

Richard, I'm going to test a few things and get back to you with results. I'm not too concerned about running it without the wire connected since I've seen in the past where the diode wire connection unplugged due to vibration while I was mowing. I didn't see anything that failed...plugged it back in and I got >14 volts DC at the battery.