John Deere 850 electrical mystery

[careyo63]

Good!! Glad your up and going. If your going to JD. I would get all of the maint. filters Oil,Air and Fuel while your there and go ahead and catch up on everything.

Carey

 

[Soundguy]

glad you found it.

looks like posters 2, 5, 7 front the first page wear all good guessers.

soundguy

 

[wsg850deere]

Not sure if anyone is still out there but my 1982 850 ran like a charm till last fall. Then a symptom appeared as if the PTO safety switch would go to safe mode. It'd run, I'd use the brush hog thus engaging the PTO switch, then I'd turn it off, and it wouldn't start again, a day or so later, it'd start right up like the switch had clicked back.

QUESTION 1
How do bypass this switch to see if it's part of the problem? Put the wires together is how I'd do it I guess.

QUESTION 2
At the moment, my tractor needs to be jumped to start. The jumping takes an unusually long time to accomplish +-5 mins before it'll turn over and start although it "clicks" right away. I assumed a new battery was needed ($175???). But I just had a "house call" and the tractor mechanic thinks it's the voltage regulator ($350 plus labor???) Does that make sense?

To summarize the steps suggested in other posts and what I'll do before spending the money:
1. clean all terminals
2. check all cables
3. measure voltages at different tractor engine speeds

I'm pretty handy and can replace the regulator itself and I see solid state ones online for about $50.

Any other thoughts?

Thanks in advance,

WSG

 

[Soundguy]

see if your battery will charge up on a slow charger. if it will charge up. do it. then try the tractor to see if it starts normal. if so.. check voltage while running.. should be 13.8-14.4 when running and revved up. before starting. charged bat should be 12.6

While it COULD be you have a bad charge system.. it does not use the charge system to start.. so lets troubleshoot that.

other things like dirty ground conenctions and bad battery terminal end / cable end connections take a toll on starting capability.

 

[wsg850deere]

Thanks Sound guy, the battery was shot and I needed a new voltage regulator which I'm putting in this weekend!

 

[Soundguy]

glad you found it.