Key switch not cranking motor

[Willy21]

I have a 95 Simplicity Coronet hydro with a 12.5 hp B&S it dropped the intake valve before I bought it. I have since repaired that and have used the unit a few times last year to mow. The previous owner told me he had a problem with the key switch and has been using a wire to supply power from the battery to the starter and that worked ok. I have since replaced the battery added a battery tender and replaced the key switch and solenoid, and nothing improved. I have started to go thru the wiring and found a few places where the wiring insulation got chaffed. I repaired the damage and it still won't crank with the key. I started checking all the plug connections in the harness looking for something loose or damaged. Now other than repairing the insulation that I found damaged I haven' t changed anything and now it won't even fire with jump starting the starter( it cranks but doesn't fire) there is a part next to the solenoid that simplicity calls a module. About eight wires terminate into this and they are encapsulated in silicone. It has like a 6" long wiring harness attached to it with a quick connector. I'am not sure of the exact function of this part or how to test if it's bad. I do know that it's about $60 from the dealer and would like to know if it's bad before shelling out the money. I might be overlooking something, the coil wires on the solenoid are getting power but the solenoid is not transferring the power from the battery to the starter to turn the motor over. Any help would be appreciated.
Thanks
Bill

 

[J_J]

Are you saying that you can not get it to crank by bypassing the wires to the engine. Does the engine have electronic ing?

That module you mentioned might contain all the interrupt, grounds and voltages from the seat interrupt, and other devices. Do you have a wiring diagram, and a meter? If so, it should tell you the readings for all the circuits. If not, then the factory repair manual is necessary.

Can you apply 12 v to the start terminal solenoid. Remove any wires from the start terminal before applying 12 v. If it has a kill wire remove it, but use it to kill the engine should the engine run.

 

[Willy21]

Hi,
Yes I do have a meter and a test light but no prints. I can get the motor to crank by applying 12 volts to the starter but it won't start anymore ( it used to start this way). I have already checked that the seat switch and the switch off the brake pedal are both up. The small terminal on the solenoid gets 12 volts when the keys is turned but the solenoid is not picking ( doesn't work with either the new or old solenoid). Not sure if that helps answer your question or not. Thanks for your help.
Bill

 

[J_J]

Can you apply 12 v directly to the starter, bypassing the solenoid. If not, check all the ground wires, if still no start, replace it.

 

[Willy21]

Yes I can apply power to the starter and the starter does everything that it is supposed to do (it cranks and engages the flywheel ) my two problems are #1 I can't operate the starter off the key switch ( it's not getting power from the solenoid) and problem#2 is even if I do get the motor to crank over by applying power to the starter it has no spark and won't fire. I have checked the switch on the foot pedal (brake or neutral switch) and the seat switch for continuity and they are functioning properly.
Thanks again,
Bill

 

[Willy21]

I just checked with a test light and I have power on the solenoid on 3 of the 4 terminals ( the two small terminals are hot and the large terminal from the battery is also hot but the one going to the starter sill has no voltage on it. The solenoid is new but it almost seems like it might be bad???

 

[J_J]

The cable going to the starter should not have any voltage until the solenoid pulls in and the contact ring in the solenoid transfers 12v to the starter.

I would run a new wire from the S terminal on the ign switch to the S terminal on the starter. If you can apply 12v to the S terminal, and the starter turns, then the new wire from the switch should fix that part.

If the electronics for the ign circuit are in that module, you will need a manual.

 

[Willy21]

There isn't a problem getting the voltage to the start terminal (the two small terminals on the solenoid) when I turn the key to the start position I have power on both the small terminals and obviously the terminal going to the battery. But the terminal going to the starter never gets any voltage. It's a new solenoid and it's doing the same thing the old solenoid is doing. But the good news is ( i'am hoping this is good) that I have spark again.

 

[Willy21]

I know this is a stupid question but can a solenoid be hooked up wrong? It just seems like everything should be working and i'am just missing a small detail.

 

[bakerg]

There isn't a problem getting the voltage to the start terminal (the two small terminals on the solenoid) when I turn the key to the start position I have power on both the small terminals and obviously the terminal going to the battery. But the terminal going to the starter never gets any voltage. It's a new solenoid and it's doing the same thing the old solenoid is doing. But the good news is ( i'am hoping this is good) that I have spark again.

Shouldn't you have 12volts across the 2 small terminals when the key is turned. 1 terminal should have a wire from the key switch and the other small terminal should go to ground. If I am understanding right if you are getting 12 volts on both small terminal, it sounds like there is a bad ground.