John Deere r72 won't start

[allz28]

MOWER is fixed FOR REAL this time! Yes!

You nailed it, Lawnranger. Couldn't have done it without you. The problem was that where the coil ground wire connects with safety switch ground wire, it was touching metal and getting an accidental ground.

Thanks again!

 

[Lawnranger]

The safety switches will ground the coil in the event of an unsafe condition such as you fell off the mower while the blades are engaged. The "operator presence" switch is in the seat and if the PTO is engaged and the you lift your weight off the seat, the switch will ground the coil which in turn kills the engine. Now the question is which switch is grounding the coil? I'm a little concerned about the black wires you connected to ground at the solenoid. Usually there is a feed wire coming off the large post of the solenoid that is directly connected to the battery and this wire feeds the wiring harness up to the ignition switch so until you get a schematic and verify what that black wire is for then we may be chasing the proverbial tail.

 

[Lawnranger]

I just saw post #11. Congratulations! Now what about that black wire I mentioned in post #12?

 

[allz28]

I'm assuming that black wire is a ground. I still have it hooked up to the solenoid mounting bolts and everything is working just fine. In fact, i just finished mowing the yard.

 

[Lawnranger]

Hopefully it is indeed a ground but I'd still get a schematic out and look it up.

 

[khunsinger]

I have a r72 John Deere that we are working on in my ag class. I am the one in charge of it and am at a loss. It's not starting. I have power to the solenoid and back to the key switch. Is it the key switch or is it something to do with a safety feature?

 

[BlazNT]

I have a r72 John Deere that we are working on in my ag class. I am the one in charge of it and am at a loss. It's not starting. I have power to the solenoid and back to the key switch. Is it the key switch or is it something to do with a safety feature?

Start your own thread and give us more information and we will be able to help. We are not there so we do not know what you have done. We also can not see or hear what it is doing. You have to let us know all of that.

 

[khunsinger]

I pulled off the PTO lever and all 4 wires disconnected leading my to believe that my ag advisor had someone else try to work on this mower. I do not know in which order they go in. Does anyone have a picture or something like that, that will tell me which wire goes where. There is also one hot wire in there

 

[bertsmobile1]

Well as this IS A LEARNING process we will play teacher.
Q1) what does the PTO switch do ?
A if you don't know go to the JD web site and read the owners manual

Q2)
Now that you know what it is supposed to do which wires go to the clutch and which wires are in the start circuit ?