D 170 is shorting the 20 amp fuse

[blarneyman]

I was mowing and when I stopped. It would not start again. Replaced the 20 amp fuse and it started. Then quit after I engaged the PTO. Replaced the fuse again and it ran for 10 minutes with the PTO engaged then quit. I've looked for visible shorts but nothing I can see. Any ideas? Thanks

 

[Auto Doc's]

Disconnect the PTO and run it around to see if it still happens. A seat switch is also suspect, so check all of that wiring. It only takes one tiny rub through or pinched area to pop the fuse.

 

[StarTech]

Hmmm I trying how a normal ground [- dc] seat circuit will short out the positive [+ dc] circuit.

I me it sounds like a partially shorted PTO clutch field winding.

 

[Auto Doc's]

Hi StarTech,

I do not have the variety wiring diagram available to study (online is a crap shoot). I recently dealt with a JD 757 that had [+ dc] run through the seat switch and that came to mind. I know JD has done some strange things on many of their mowers.

Like you said the PTO could be the issue. Maybe the air gap is too wide, and the windings have been repeatedly overheated to the point of failing.

 

[StarTech]

Hi StarTech,

I do not have the variety wiring diagram available to study (online is a crap shoot).

You mean a diagram like this?