I have a john deere lx277 that I have had for 15 years. It has always started hot or cold and never let me down. I have now developed a problem with it starting. When cold it cranked right up and ran fine. When It got hot it wouldn't start no cranking no nothing.I would use the leaf blower on engine and after 2 or 3 minutes it would crank right up. now it wont start at all hot or cold. However I went out this am and tried it and it cranked right up ran it for 2 minutes shut it off and it again wouldn't start no cranking no nothing. Just tuned, new filters, battery full charged, new synthetic oil,
I tried to out box the soloniod and it made a whirring sound but did not engage to the engine. what do I check next. Seems odd that it starts when it feels like it.
I'm assuming when you say the engine won't crank, you mean the starter does nothing.
Sorry for the confusion, but some folks use the word 'crank' to say the engine turns over but won't fire.
But, in your situation, since you have tried bypassing the starter solenoid, I will assume you mean the starter won't crank.
1. The first thing I usually do here at the shop is pull the purple wire off the solenoid spade terminal.
2. Make sure the PTO switch is off, and lock the parking brake.
(The brake switch overrides the seat switch in the starting circuit, so you can be off the seat while doing this test.)
3. Turn your key to the start position and see if you have 12 volts DC (battery voltage) at the purple wire.
*If you do, the problem is the solenoid and/or starter.
*If you don't, the issue is in the wiring or one of the switches.
This simple test gives you a direction in which to start finding the problem.
Let me know if you need a wiring schematic to trace the current through the switches.
I work at a dealership and can attach a copy here.
I can also give you more detailed info if you need to start tracing current, but we'll go down that road once we see what results we get with the above test.