Deere 425 Electrics issues Quits when brake released or PTO engaged

[Trevj]

Got lucky (maybe ) and bought a JD425 with a 54 inch deck and a snow blade.
Was a bit of a crapshoot, but I think it paid off. The description said it had engine problems, which after an hour or two digging about, it seems the engine problems were some broken or missing wires.

I found that the fuel pump disconnect wire was clipped off at the loom and at the connector beside the engine. Replaced that, and reattached another partly cut wire. It looked like it had been chewed by rats.

Anyhoo, got the fuel pump working, drained the skanky gas out, and the engine fired right up, and purred. Nice!

Problem is, the engine cuts out when the PTO(front only on this one) is engaged, or when the brake is released.

Anyone had similar problems? Where was the fix?

I figure I can bypass all the interconnects and run it like any other implement, or I can dig through it and figure it out, and run it as it was supposed to be. I'd rather have it the way it is supposed to be.

While I was mucking about, managed to short the key switch to the frame, there was a puff of smoke from a trace on the electronics board. I ran a bead across that, and all seems well there. I'm not at all adverse to soldering in some new components, if I have to, as there does not seem to be any IC's on the board, just a couple relays and some other basic discreet components.

But if it comes down to it....Not afraid of buying factory parts, either.


Anyone run into this type of problem in the past? I'm wondering if someone rewired something in backwards, or if there is a stuck switch in the system.

Am printing off the troubleshooting guide from the shop manual I found online. <sigh> Things to do...

Any inputs appreciated, thanks!

FWIW, I got the tractor and attachments for just over $1K. Shows a bit over 2K hours on the meter, but was a government owned machine, so seems to have seen real and regular maintenance, at least for most of it's life.

Have not yet checked for the cam gear. Will soon.

Trev

 

[aczlan]

Bad seat switch or wiring problems leading up to the seat switch.
The behavior you describe is what happens when you try to move or engage the PTO with no one in the seat.

Aaron Z

 

[Trevj]

Bad seat switch or wiring problems leading up to the seat switch.
The behavior you describe is what happens when you try to move or engage the PTO with no one in the seat.

Aaron Z

Seat switch is not present. There is a chunk of wire in the connector for the seat switch right now. I'll check that it is actually connected, though. IIRC the seat switch has to be made to get the engine to crank, too.

Going to go run through the meter checks per the PTO Troubleshooting checklist. The manual says to do that series of checks for these two symptoms.

Thanks!

Trev

 

[aczlan]

Not sure on yours, but the Deeres and the Cub Cadets I have worked on do not require operator presence to crank, just PTO off and brakes on.

Aaron Z

 

[Trevj]

Well, unless I can get it to quit reliably again, I'm chalking this up to some long term storage issues, strongly suspect the brake switch or the PTO relay.

Was playing around with the brake pedal with the key turned on, but the motor not started, and when I bumped the pedal up and down a couple times, the red LED on the controller card started flicking on and off in time with, and I could hear the relay starting to click. Went through a couple cycles of it reacting, then not reacting, to the brake pedal being released, then...it worked!

<shrug> Dunno. Would rather have been able to pin it down, but I'll take this!

The mower deck works pretty well, but I need a set of the caster wheels for it. Soon.

Cheers
Trev

 

[Gittyup]

If the brake is set, the PTO will not start. PTO should simply not come on if the brake is set; should cause a stall. So, not sure how you were able to separate these two. If it stalled when you released the brake, how'd you get the PTO to stall it? Does sound like might be seat switch as the brake has to be set to run the tractor without being in the seat. Brake switch could be out of wack too. Sounds like the wiring harness is hosed up a bit. However you got a bargain. That's pretty low hours and one of the newer 425's.

 

[aczlan]

If the brake is set, the PTO will not start. PTO should simply not come on if the brake is set; should cause a stall.

Ummmm, this has NOT been the case on any machine I have worked on or used. That includes many Cub Cadets, Deeres, Kubota, Exmarks, Huskvarnas, etc.

Aaron Z

 

[Trevj]

If the brake is set, the PTO will not start. PTO should simply not come on if the brake is set; should cause a stall. So, not sure how you were able to separate these two. If it stalled when you released the brake, how'd you get the PTO to stall it? Does sound like might be seat switch as the brake has to be set to run the tractor without being in the seat. Brake switch could be out of wack too. Sounds like the wiring harness is hosed up a bit. However you got a bargain. That's pretty low hours and one of the newer 425's.

Dunno for sure that there was any difference in the way the tractor reacted to having the switches operated. Suspect that both were the result of the same interlock circuit.
At first glance, it looked to me like the PTO switch being pulled on, and the brake being released, both of which killed the engine in their own turn, were separate items to troubleshoot, but it seems after digging in to it that they were both part of the same circuit. Can't have one without the other, from appearances.

Probably says that somewhere in the operators manual, but I missed it...

Operating

Yeah. Looks right.

I'm still of the theory that the brake switch may be a bit funky, or that there was some stickiness to the PTO circuit relay from sitting too long unused.
Working again, for now though.

Yep, I figger I dun good!


Cheers
Trev

 

[Gittyup]

Ummmm, this has NOT been the case on any machine I have worked on or used. That includes many Cub Cadets, Deeres, Kubota, Exmarks, Huskvarnas, etc.

Aaron Z

Typo: I meant that the tractor should NOT stall: This tractor won't start if PTO switch is engaged or if brake is not set. While running, if brake is depressed, PTO will shut off, requiring cycling of the PTO switch after releasing the brake but it won't stall as a result of pressing the brake pedal. Brake has to be set to get off the seat with the engine running. Don't know how other makes and models work; but this is how this tractor works.

 

[Gittyup]

Interesting that the operating instructions posted in this thread say that the the PTO shuts off when traveling in reverse. My mower keeps running in reverse (thankfully). Maybe this is a change for newer models (mine is a '95) or maybe they mean the rear PTO? But that doesn't make sense either. ???Confused by that information???