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model 74301
serial 230001142

Hello, I have a toro zero turn mower I bought used and all worked fine till today. I have a no crank issue where motor never turns over. I can crank mower with screwdriver by jumping the solenoid. When using the key I can not crank the mower. I can hear a small tick back at the carb but really im not sure if I hear a click or not, do not want to mislead. Here is what ive done so far.


1. replaced the two fuses under the seat
2. tested solenoid get 12 volts to front nothing to back
3, no volts to starter either of course
4. replaced solenoid
5. I have cut the wires going into the seat saftey switch and twisted them together
6. new battery and it tests good

can anyone help me where I should start next please?

There are 2 safety systems fitted to ZTR's
One kills the engine should you fall off which you have now dissabled.
The other prevents the engine from turning over to protect the mower which is the one giving you grief.
Toro has all their wiring diagrams available on line for free.
They also did a stand alone manual called the "Demistification Guide".
Every thing you have to do to start the mower, levers in neutral, parking brake on, blades turned off will have a switch dissableing the start if they are not in the correct place.
One of these is not working. Add to that there is a relay ( sometimes two relays ) which occasionally goes bad.
So start by going to Toro's web site, customer support, get manuals, and enter the numbers you have posted here.
Print out the wiring diagram for your mower as large as you can then trace the circuits from the starter solenoid back to the ignition switch.
Colour in this ( these ) circuits then starting at the control wires to the solenoid work your way back, testing each switch as you find them.
A PIA job, set aside a full day for it but there is no shortcut.

there is 6 or 7 different service manual to choose from and I opened up each one and it looks like a manual that groups 5 or 6 mowers into one manual and dedicates a few pages for each. Ill look trough that. I was able to find from the operation manual my specific demystification guide and wiring diagram. I ordered two safety switches for the lever arms and a relay.

Ill replace and report back.

Can you think of anything else besides keyswitch or pto switch that would cause this?

Its disappointing but, the toro manual shows a pto switch with 5 prongs three top and two bottom and my pto switch is 6 prong three up top and three in the middle. ughhhhhhhhhhh

manual pto
l l l
<<<<< nothing here
| |

my pto switch
| | |
| | |
<<<<< nothing here

Normally the go is to work out which wire goes to what then bypass each switch one at a time till you find the culprit

bertsmobile1 said:

Print out the wiring diagram for your mower as large as you can then trace the circuits from the starter solenoid back to the ignition switch.
Colour in this ( these ) circuits then starting at the control wires to the solenoid work your way back, testing each switch as you find them.
A PIA job, set aside a full day for it but there is no shortcut.

Click to expand...

His looks to be more of pia. Looking at the wiring diagram goes from solenoid to ignition switch no switches on that wire. They put it on two other wires(safety switches & relay) that have to complete the circuit then transfer to start circuit to solenoid(wire tab). Hope he doesn't have a hungry mouse.:wink:
Perhaps he will get lucky parts replacing.

They did not cost much on partstree

Anyways, here is the latest. Replaced relay, both lever arm safety switches, its now down to the PYO or the switch. Since those cost a lil more I tested those. The switch for key checks out, but the manual and the type of PTO I have does not jive or match up so I am confused on testing so spending the 22 dollars for a PTO

Will report back after replacing pto switch

More to come and thanks for the replies

===========UPDATE=============

new PTO switch and it will crank an blades run

after a hour of cutting yard, it shut off and will crank back up not using blades, when I go to cut again it will cut for a short while then shut off again.

Is is implied that a riding lawn more should have a special proprietary type of battery that I am not aware of to sustain the pto clutch & I am just a idiot?

Who has run there mower on a regular store bought batter?

I got a brand new battery from battery source.

If you disengage blades when it starts to cut off, does it help?

Mower batteries and car batteries are essentially the same.
The only real difference is the physical dimensions and the type of posts.
Mowers use flat post with bolt on terminals
Car batteries use round posts with clamp on terminals.

On a mower it is best to use a sealed battery and if possible an AGM type because they get bounced around a lot and the AGM batteries are a lot more shock & vibration resistant than flooded cell car batteries.
If the battery is not being recharged properly by the mowers alternator then it will drain the battery and when t gets to around 9 to 10 Volts the solenoid on the carb closes shutting off the fuel & the mower stops.
A freshly charged battery should read 12.5 to 13.5 Volts sitting in the mower with everything turned off.
When the engine is started and the electric PTO engaged you should still see 13 V minimum at the battery or it will not be able to get recharged.

The Toro manuals you have downloaded have instructions for checking the AC and DC output of the engine.
Do that but you must start with a fully charged battery and let us know the results.

When you turn off the blades when you hear it starting to shut off it does not help. However, I want to test that again tommorow to give you a more accurate answer. I do recall shutting off PTO once and it seemed liked it extended the run time but eventually shut off. I will test again tommorow

I will do the other tests tommorow too. I need this sucker cutting before this north florida spring kicks off full on bloom sprouting stuff up everywhere

Thanks yall , we will get to the bottom of this

This is exactly what happens when the charging system is not up to snuff.
The load applied by the electric PTO causes a voltage drop which shuts down the carby solenoid and when you turn off the pto the voltage returns high enough to reopen it & keep the engine runing.
Your PTO might have been the guilty party all along or the alternator / rectifier might be on the way out.
Do the tests as per request in pervious post.