z425 will not start

ACF

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have a john deere z425 that owner has replaced the key switch starter, voltage regulator and coils and did some wire cutting. the engine will not turn over using by jumping solenoid but there is no spark from coil. do not if the owner used the correct replacement parts. , my gut tells to replace the coils and see what happens. looking for any help to fix thanks
 

Auto Doc's

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Hello ACF,

What is the PIN on the white sticker on the machine? What are the numbers the engine label or stamped into the top of one of the valve covers.? JD made several versions of the Z425, they are not all the same.

I hate when owners dabble with stuff before asking for help. What wires have been cut?

"will not turn over jumping the solenoid but there is no spark" Did you proofread what you wrote?
 

sgkent

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multiple problems may be here. Chase each one individually. Get the starter working, then get the ignition working. If it has an electronic module that could be the culprit. ASK the owner WHY he was monkeying with the wires. Sounds like something failed then he made things worse. Keep track of your hours and bill accordingly.
 

Auto Doc's

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Hello sgkent,

Never had both coils fail (if it is a V-twin). They will still run, but underpowered on one coil. This one is getting interesting.

I've got several owners like this that just start swapping (Amazon) parts out of desperation and it is a real pain to undo all the experimental carnage in most cases.
 

StarTech

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Hello sgkent,

Never had both coils fail (if it is a V-twin). They will still run, but underpowered on one coil. This one is getting interesting.

I've got several owners like this that just start swapping (Amazon) parts out of desperation and it is a real pain to undo all the experimental carnage in most cases.
Always not fun and causes a lot of extra that customer must pay for. And I had to ignore a customer that wanted me to sharpen a set blades on Sunday. My lord it is my only day off to rest besides I think 60 hrs a week is enough aggravation. And a computer failure doesn't help.
have a john deere z425 that owner has replaced the key switch starter, voltage regulator and coils and did some wire cutting. the engine will not turn over using by jumping solenoid but there is no spark from coil. do not if the owner used the correct replacement parts. , my gut tells to replace the coils and see what happens. looking for any help to fix thanks

I thinking there is terminology terms problem in the OP post. He may be saying the engine cranks but will not start up running.

Disconnect the interlock relay and test. Sounds like safety circuit problem keeping the ignition coils grounded. And cut wires must be re-spliced before proper troubleshooting can occur.

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Boy what a learning curve this Win 10 has and not looking forward to Win 11. Everything is different. Learning on the fly is always a challenge I am not looking for.
 

ACF

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Hello ACF,

What is the PIN on the white sticker on the machine? What are the numbers the engine label or stamped into the top of one of the valve covers.? JD made several versions of the Z425, they are not all the same.

I hate when owners dabble with stuff before asking for help. What wires have been cut?

"will not turn over jumping the solenoid but there is no spark" Did you proofread what you wrote?
do not have the white sticker but engine model is 40h777-0182-g5
 

Auto Doc's

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Hello ACF,

All JD mower equipment comes with a durable product identification number (PIN). Some are fairly well hidden on the frame behind one of the rear tires on Z-Tracks.

This may help with parts sourcing. There are lots of parts variations even for this engine depending on what machine it was installed on.

 

StarTech

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Since no one is willing or able to post these, here is the schematics for the Z425 with Briggs engine.

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