I can't think of a reason..

[hanz63]

My waking thought: Why ultimately are Briggs voltage regulators wired hot off the chassis rather than being on a switched circuit, such as with the carb solenoid?>

[KE4AVB]

As long as I have been working electronic dc power supplies have been done this way. The designer are depending on the dc blocking capabilities of the transistor(s) to prevent feedback draining the batteries. Adding a relay or SCR and additional wiring is unnecessary and actually can induce more areas that can fail. Some regulator are actually switched off while still being hardwired in. An example is the Kawasaki 21066-2070 where they switch the regulator off so there is no output even with the engine running unless switched on by the voltage from the battery. No battery, no output.

[hanz63]

I tend to see parasitic draws from them. The 15s do OK with a good regulator, but the 9s always seem to have a larger draw regardless.

[KE4AVB]

Han63, You're going need to enlighten me a little here what you are referring to as 15s and 9s. Also what amount of draw as I need to do some research on the setups to see if I figure what is going on?

[hanz63]

I was referring to 15 amp found on many Intek twins and 9 amp which is found on many of the singles and some manual PTO twins. In looking for a draw , disconnecting the + wire on the regulator and the draw disappears. A new regulator with a working diode inside all is well , at least seems to be on the 15 amp. The 9 amps , working as designed or not still have a parasitic draw. At least my observations that some of these don't shut down and why would the regulator need to have power 24/7.

[KE4AVB]

Hmmm, Something new me to check out. I have seen any problems with them here but will start looking at this as mowers come in. It will me some time to get any data on my end as things are randomly coming in. Currently on the yard is Cub with Kohler and a Huskee with a Briggs opposed. My personal mower both have the dual circuit setups.

The of the Huskee has a way too small of battery in it 140 CCA battery and it take every thing it can give to start up the engine.