Toro Timecutter SS5000 - starter keeps running with key off

[Auto Doc's]

That might work.

The idea is to keep "flyback" voltage from activating the starter solenoid and keeping it engaged.

 

[Grunkle]

Sounds good. I'll give it a try and get back with you all as soon as I get it installed.
Thank you!

 

[Midnight_Rider]

Under the seat is a wire connector with all of the wires going into it... Unplug it,and see if it shows any signs of corrosion on any of the pins on either connector... I have the exact same model,and had the exact same issues after I stored it outside uncovered and it rained... The seat safety switch will probably act up next.. You can clean the terminals and pins up and maybe it'll start working right again,or find the correct circuit to the starter, unpin both sides and make a straight connection alleviating the corrosion which is causing the issue... Or cut that wire and run it to a mpmentary switch and then to the starter solenoid and use that for starting...

 

[Grunkle]

Victory!!!!
I installed a resistor inline on the blue wire between the ignition solenoid and the brake actuator.
I also checked for corrosion on any pins at the connectors basically everywhere on the mower.
Hooked the battery back up, and the engine fired right up and shut back off with the key! Just like it's suppose to do. So I told my wife we can cancel returning the new brake actuator cuz now (with some help) it's working.
Thank you ALL for your input and help! I can't thank you enough!
Can't wait to use the mower now, after an oil change and blade sharpening, of course.

 

[Auto Doc's]

A resistor or a diode? what was the number of the part you used and source?

I'm sure there will be other folks who run into this kind of problem in the future.

 

[Grunkle]

The part is a Briggs and Stratton 393456 alternator diode assembly. It has 2 wires(1 red, 1 black) on one end and a plug with 2 pins on the other. I looked up the schematics for its installation and found the diode is in the red wire, so the black wire I did not connect, just tucked it into its own sheath. I connected the red wire to the blue tail near the solenoid, and attached a "bullet plug" on the blue wire to the brake controller, and plugged it onto the pin for the red wire of the diode assembly.
I have to assume I got it right, cuz it works perfectly, and it wasn't without the diode installed. I paid around 20 bucks for the part at a local auto parts store. Could have gotten way cheaper online, but didn't want to wait a week for shipping.
There are probably better options out there, but this one was readily available and easy to install.
Aside from the shrink tube, you wouldn't even know it wasn't part of the original harness. I secured it to the existing wire loom with a small zip tie and tucked it under the mower body above the brake controller, out of sight.

 

[Auto Doc's]

Hi Grunkle,

Thanks for the parts info and the solution you came up with. That diode should be sufficient to protect the circuit for years to come.

There are many folks who do not understand the purpose of a diode in a circuit. A circuit diode can resolve a lot of strange electrical problems if installed correctly.

When I worked for a local John Deere dealer as a service manager years ago, I was always showing my techs how to resolve strange electrical issues like this.

 

[Grunkle]

Thanks to all of you who helped walk me through it.
One thing I like to do with mowers is remove the mower deck, clean it well, and paint it with bed liner. It cleans off easier, and absorbs impact from rocks so the paint doesn't chip on the outside of the deck. It also prevents rust from acidic grass. It makes the deck last WAY longer, and is easy and fairly cheap. When done mowing I run front wheels up on car ramps so I can hose off under the deck. My mowers look like new and last a long time. And oil changes every 60 hours makes a happy motor, especially in dusty conditions.