G1900S with intermittent won't crank issue

[Stampeder]

I recently got a G1900S with only 190 hours on it. It sat in a garage for almost 20 years.....
It has a weird intermittent issue in that it won't crank. All the lights come on as well as the glow plug timer and other lights work.
Then after a while of leaving it sit is will start.
When it is behaving like this, if I put it in park and get up off the seat it kills the engine.
Under normal operation (when it starts right up the first time) I can put it in park and get off the seat and it will continue to run.
Any thoughts?
Thanks.
Glenn...

 

[Roadworthy]

I'd probably start by going through all the operator presence sensors, especially the seat switch.

 

[lmichael]

In the end you will drive yourself crazy. A helper relay is the way to go. It's simple, effective and keeps all your safety equipment intact. It simply allows enough current to the solenoid to start the engine.

 

[GreenDuramax04]

From your description I would think that the safety switch on the PTO is the culprit. (Its probably sticking) The engine will not start with the PTO engaged and if the PTO is engaged the seat sensor is active.

The switch is under the dash below the PTO handle. You need to take off the screen under the dash for access.