Simplicity Courrier/25 HP B&S, ZT-turned mower off and won't start.

4mustangs

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  • / Simplicity Courrier/25 HP B&S, ZT-turned mower off and won't start.
I have completed all those inspections. Pulled all connections off, cleaned, and reconnected. Battery cables are clean, and all connections are secure. My mower is garage kept and inspected every time I clean it off after use. All power/electrical lines are in good condition with no wear areas, breaks, or rusted connections or components. At this point, I am thinking it is the ignition switch, the seat safety switch, or possibly the starter solenoid. I have someone coming out to test these things on Sat. Thanks for everyone's input.
 

STEVES

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  • / Simplicity Courrier/25 HP B&S, ZT-turned mower off and won't start.
Also check for Bad PTO switch, not that it is just off.
 

Freddie21

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  • / Simplicity Courrier/25 HP B&S, ZT-turned mower off and won't start.
Jump 12v to the small connection of the starter solenoid and see what response you get. Nothing, probably a bad solenoid or ground on it. Clicks and rotates starter, then you're back to checking safety's and wiring.
 
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  • / Simplicity Courrier/25 HP B&S, ZT-turned mower off and won't start.
I have completed all those inspections. Pulled all connections off, cleaned, and reconnected. Battery cables are clean, and all connections are secure. My mower is garage kept and inspected every time I clean it off after use. All power/electrical lines are in good condition with no wear areas, breaks, or rusted connections or components. At this point, I am thinking it is the ignition switch, the seat safety switch, or possibly the starter solenoid. I have someone coming out to test these things on Sat. Thanks for everyone's input.
I had an identical problem with my Husqvarna that would come and go so I was sure it was a safety interlock issue. New seat switch, cleaned ignition contacts, checked fuses. It'd start and run for weeks then act up. Replaced the starter solenoid and haven't had an issue since.
 

Cajun power

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  • / Simplicity Courrier/25 HP B&S, ZT-turned mower off and won't start.
when you say "nothing"...please elaborate.

for example...

1. when key turn to START = you hear the anti back fire solenoid clicking or not?
2. when key turn to START = the engine rolls over but does not start?
3. when key turn to START = engine rolls over sometimes, but hesitates to roll over ...like heavy resistance?
4. when key turn to START = engine rolls over and starts, but then when key returns to RUN, engine stops ?

please explain the symptoms with a little more detail. Because it matters these details. "nothing" can mean alot of different things to alot of different people.

Here are some things wrt to the above list of symptoms.

1. if the anti back dire solenoid is not clicking, then either the circuit to it is borked or the device itself has failed. This can cause engine start problems...usually this means the engine may run for a moment then gets starved of fuel.
2. if the engine rolls over but does not start, we can assume the starting circuit (and safety switches) are operating normally...look for fuel or ignition related problems.
3. if it rolls over sometimes and sometimes it struggles to roll over...then we can again assume the starting circuit (and safety switches) are operating normally, but there is something causing resistance to turning engine over. This can be related to a poor battery state of charge or a bad connection, or a failing flywheel starter motor/solenoid....make sure battery is fully charged and check all power AND ground connections...look for any corrosion and see if you can bypass the starter solenoid to test ...it may have failed internally. Likewise, try the same with spark plugs removed. It's possible the engine has a problem and this creates alot of resistance to turn it over. If it turns over easily with sparks plugs removed...then, look at valves clearance.
4. if engine rolls over and starts but when key returns to run and engine stops means that there is a fuel/carb problem most likely. check make sure the choke is not stuck and the spring to it is not broken or loose...the choke valve must be able to rotate easily. Also, sometimes a failing ignition module (coil) can produce these symptoms....It can start and run momentarily, but then fail to produce an adequate spark when "excited" under load. Make sure the spark plugs and spark plugs wires are not damaged too.

report back what you mean by "nothing"....The list above may or may not change with recommendation based on the details of what you mean by "nothing"

hope this is helpful
 

4mustangs

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  • / Simplicity Courrier/25 HP B&S, ZT-turned mower off and won't start.
when you say "nothing"...please elaborate.

for example...

1. when key turn to START = you hear the anti back fire solenoid clicking or not?
2. when key turn to START = the engine rolls over but does not start?
3. when key turn to START = engine rolls over sometimes, but hesitates to roll over ...like heavy resistance?
4. when key turn to START = engine rolls over and starts, but then when key returns to RUN, engine stops ?

please explain the symptoms with a little more detail. Because it matters these details. "nothing" can mean alot of different things to alot of different people.

Here are some things wrt to the above list of symptoms.

1. if the anti back dire solenoid is not clicking, then either the circuit to it is borked or the device itself has failed. This can cause engine start problems...usually this means the engine may run for a moment then gets starved of fuel.
2. if the engine rolls over but does not start, we can assume the starting circuit (and safety switches) are operating normally...look for fuel or ignition related problems.
3. if it rolls over sometimes and sometimes it struggles to roll over...then we can again assume the starting circuit (and safety switches) are operating normally, but there is something causing resistance to turning engine over. This can be related to a poor battery state of charge or a bad connection, or a failing flywheel starter motor/solenoid....make sure battery is fully charged and check all power AND ground connections...look for any corrosion and see if you can bypass the starter solenoid to test ...it may have failed internally. Likewise, try the same with spark plugs removed. It's possible the engine has a problem and this creates alot of resistance to turn it over. If it turns over easily with sparks plugs removed...then, look at valves clearance.
4. if engine rolls over and starts but when key returns to run and engine stops means that there is a fuel/carb problem most likely. check make sure the choke is not stuck and the spring to it is not broken or loose...the choke valve must be able to rotate easily. Also, sometimes a failing ignition module (coil) can produce these symptoms....It can start and run momentarily, but then fail to produce an adequate spark when "excited" under load. Make sure the spark plugs and spark plugs wires are not damaged too.

report back what you mean by "nothing"....The list above may or may not change with recommendation based on the details of what you mean by "nothing"

hope this is helpful
Thanks for the input. When the key is turned to the start position, there is nothing. There is no juice from the ignition to the starter solenoid; the engine does not turn over, the lights do not come on the engine doesn't try to start. I figured out the issue when my buddy brought his tester over. There are two fuses on the mower. I found the one and replaced it even though it was not burnt. He found the second one, and it was burnt, so I replaced it, and the mower started right up. Of course, this was after I had replaced the solenoid and the PTO switch and was thinking about buying a new ignition switch. Lesson learned. Thanks for everyone's attempt to help. I know this is a lot like someone telling a mechanic at the garage that their car is acting strange and making a noise that they can't seem to put into words and keeps everyone guessing.
 

bertsmobile1

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  • / Simplicity Courrier/25 HP B&S, ZT-turned mower off and won't start.
Good to hear you got it sorted
mowers with electric PTO have 2 fuses 7,5A for thePTO & 20 A or the mower
This is why we are always suggesting people get a copy of their mowers wiring diagram
Enjoy your $ 80 fuse , hope you did not throw out the old parts
Now go mow
 
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