JD 160 Intermittent start, low voltage at solenoid

[bigredscowboy]

I acquired a JD 160 (c. 1987) locally for a great price, with extra belts and original operators manual. Owner said there was an electrical problem. He lived on a hill so I eventually jumped the starter solenoid to drive it on the trailer rather than have to push it up hill and up the trailer ramp.

When I got it home, I tried starting it with the key to get it off the trailer. I could hear the starter gear throwing out but not spinning. After a couple of tries it spun and fired right up. Tried to back it up and no go. Trans in neutral and very hard to shift; won't quite make it into reverse. That's for another day.

So I turned it off and on several times. Maybe once out of every 5 times it will spin the starter rather than just throw out the gear. Jumped the solenoid and it spins every time. So I put a meter on the solenoid blade and turned the key several times. When it only throws out the gear, the purple/white wire gives 6-7 volts. When it spins the starter, its getting 9-10 volts. Is this indicative of a safety switch failing or a short or something else?

Thanks for your help.

Edit: Battery voltage good at rest and crank. Motor spins fast and starts up when starter finally spins.

 

[ILENGINE]

Failing safety switch or corroded terminals at the safety switches or even the key switch. Also make sure the solenoid has a good ground also.