John Deere ZTRAK 737 zero turn - runs rough - one plug

Question edited to fix all the spelling errors.

An engine needs 3 things to start.
Fuel.
A spark at the right time.
Compression.

One is missing. Lots of troubleshooting help in the videos.

https://www.google.com/search?q=John+Deere+737+won%27t+start

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It doesn't appear to be online. Contact them direct.

https://www.weingartz.com//assembly-diagram/john-deere-parts-lookup/model-z970r-ztrak-r-series-mower-z970r-ztrak-r-series-mower-pc11784-belt-idlers-covers-60-inch-mower-deck-60-inch-tcm12228-040001-/4275-36249-483761

Wiring Harness
https://partscatalog.deere.com/jdrc/navigation/equipment/63884/srch/CHASSIS%20WIRING%20HARNESS%20%28070001%20-%20%29

https://www.deere.com/en/parts-and-service/zero-turn-mowers/commercial-ztrak/z970r/

https://www.google.com/search?q=john+deere+z+trak+970r+wiring+diagram

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check pulleys and mandrels for failure/ binding

if you dont use kevlar belts,then you are wasting money,they cost more,but,they last ten times longer,use the widest width that it can handle,dont buy from jd,it will cost you 100.00,go to ebay,etc,your tensioner should not be tight enoughto stretch the belt also,here is a jd belt,you can get cheaper just make sure it looks green or red,not rubber black, JOHN DEERE oem Mule Drive Belt TCU13195 737 757 Trak below 030000

OEM Replacement PTO Belt John Deere 737 757 Zero Turn Lawn Mower
JOHN DEERE TRAK 737 757 797 60 DECKS DRIVE BELT TCU13198 12760

you could put a batter disconnect switch inline-but replacing the clutch is going to be your best bet-cheers Denny

check a ignition coil on the Kawasaki engine... if it's a Kohler, replace both coils and DO NOT go back with the DSAI or CDI ignition system

check for a spindle seizing from rust and failed bearings.

recheck the valve lash clearance

First. My disclaimer. I do not have first hand experience with your model mower.

Well, it sounds like when you engage the PTO the power to the PTO shorts to ground causing a) your charge light to come on as the voltage drops substantially and b) your mower to stall as the minimum voltage of the ingnition system is reached (or some other effect is at work). The clutch is might be internally shorted, or you may have a frayed wire in the PTO circuit. You may or may not have a PTO relay. If you do, it is sure to burn up if you continue using your mower. If you do not have a relay, you will definitely burn out the PTO switch. It is odd you are not blowing an inline fuse if this is the correct answer. Check your PTO circuit with a continuity tester to tell you if there is a short (or measure resistance directly with a voltmeter on ohms).

Not sure in the " drop rod" but they have a problem with exhaust valves sticking and pulling the guides out of head. What rod were you refering to?