What sort of a click & from where ?
a faint click from the fuel solenoid , a slightly louder one from an ignition relay or a monsterous one from the solenoid ?
If you are going tobuy parts on spec, rather than testing to diagnose th faults I will happily supply you with a list which will cost around $ 600.
If you want to fix your mower rather than fill your shelves with the good used parts you replaced you might like to try tis.
1) run a jumper from the power terminal on the starter motor , taking care that is does not make a ground contact any where.
Touch the other end to the battery + , the engine will crank if the battery, starter & ground connections are all good.
No joy then run another jumper from the battery - to a good ground point on the engine.
Starter cranks = bad ground connection ( very common )
No joy then do the above off your car battery
Engine cranks = bad battery
Does not crank = bad starter ( very rare )
From here on in it becomes very mower specific but in general you would then go back and try putting the + jumper on the battery terminal of the solenoid ( tests the battery power cable ) .
The solenoid need a trigger to fire and that comes from the wires at the base.
One only and it should go + when the key is in the start position .
While it is off, use a thin wire to bridge the battery wire and the trigger terminal
If the solenoid is good it will fire & the engine will crank.
If it does not, make a ground contact to the base as this type grund through the mounting bolts and often corrosion prevents the ground happening.
OTOH if there are 2 wires at the base, one will be power & the other will be ground and BOTH OF THEM CAN BE SWITCHED.
Solenoid is tested the same way except you need both a + & - patch cord ( thin jumper ) & polarity does not mater.
From here on in you really need a wiring schematic because you have to go back through the system to see where the bad connection is.
FWIW I use about 1/2 dozen pumpers with a spade on each end to bypass the safety switches one at a time at their plugs .
If you pull the plug from the key switch and jump B to S then when you find the problem the engine should crank which saves you growing a 3rd hand.
With mowers I am unfamiliar with, I take the blower housing off and remove the kill wires from the magneto coils jus in case I make a mistake & send power down the kill wire.
Now the killer is control modules, usually associated with the hour meter.
If your mower had an electric control panel with a fuel , seat, PTO , battery & Brake warning light on them then chances are it is also a control module.
Mower companies have been forced to fit them because the law has made them responsible for the idiot morons who should have been allowed to die at birth advising every one how to bypass safety switches and these clots following the instructions & hurting themselves or some one else.
