After warm up mower stalls , turn key off and on motor starts and runs short time and hve to repeat what could cause this?

It sounds like you have covered most of the possible issues with the electrical system. A ground issue could be a possibility, but there are other potential causes as well. Here are a few more things to check:

1. Check the wiring, connections, and terminals for the PTO. Verify that there are no loose or corroded connections and no damaged wiring.

2. Inspect the PTO clutch for wear, damage, or signs of shorting. A failing clutch can cause an increased electrical load, which can drain the battery and cause the engine to stall.

3. Check the belt tension and condition for the mower deck. A loose or worn belt can cause excessive load on the PTO and engine, leading to stalling.

check pulleys-mandrels -and bearings for failure

Use a bottle of yellow HEET dry gas to remove any moisture problem in the fuel.

Clean / replace air filter.

Top off ATF to MAX level.

Use starting fluid to aid starting.

sounds like a fouled plug.

Hi,
There is a kill switch under the seat that makes sure you stay in the seat if the mower is running...my bet is that the switch is malfunctioning and the vibration of the motor is causing it to short out...get a new switch, they can't be that much...

heatman101

It sounds like either the seat switch went bad or one of the other safty switches failed easiest way to test this is to dis-connect all wires to the motor, run a jumper form the positive post of the battery to the switch side of the stater solonoid to see if the motor turns over with everything else dis-connected if it starts start connecting wires one at a time until you get to the one tat causes the motor to quit then you have the problem circuit. It sounds to me like you either have a bad safty switch, bad key switch, bad Ground, or a faulty starter solonoid or maybe even a defective battery. Hope this helps Don

Try cleaning the throttle body. If it runs on carb-cleaner being sprayed into the intake then you have a fuel delivery problem, if not you'd be more inclined to more serious mechanical failure. I assume if you use it every day you do the regular oil changes, air filter cleaning, and air-cooling system cleaning, correct? Please indicate if you had a white smoke, blue smoke, or black smoke from the mower too. The motor spins freely when attempting to start, and just doesn't fire, correct?
-JMFT

Check the muffler, if the muffler is clogged it could cause overheating of the engine, and could keep the engine from getting the necessary fuel-gas mixture.

Drain the old gas out put new gas in then purchase some starting fluid spray into air cleaner and start repeat this, the motor may stall a few times but eventually it should clear out the stale gas and run.

I have same mower and just fixed what seems like a similar problem description. I had gone down the fuel system route and the symptoms just didn't add up. Stopped abruptly w/o sputtering once I reached warm-up temp. Replaced the solid state ignition (34443C now part number 3444D). Problem corrected and just mowed my 1/3rd acre w/ no issues.