Repairs Electrical problem

My church has a Grasshopper 721D that we are continuing to have trouble with. Here is what it is doing right now. The only way we can get it to start is to heat the glow plugs then turn the key to the run position and then use a screwdriver to jump the starter over. When you try to turn the key all the way to start nothing happens. Once we have jumped the starter over with the screwdriver the mower will run perfectly. We have replaced the starter twice, all fuses are good, new brake switch. Also at this point we have bypassed the seat switch because as soon as you open the arms to get off of the mower it will stall. This happens even if the brake is on. I am just beginning to learn about these grasshopper mowers so let me know what other info you need to help me get this resolved.

Thanks so much for you help.

Have you tested the key start switch? It sounds like its bad.

BlazNT said:

Have you tested the key start switch? It sounds like its bad.

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Sorry i forgot to say we just replaced the key switch.

Sometimes a bad PTO switch will make the mower hard to start.

bobbysr said:

Sometimes a bad PTO switch will make the mower hard to start.

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We are completely confused as to what is happening. I guess the PTO switch is a possibility. Is there any way to test the PTO switch to see if it is functioning correctly. Once we jump the starter over with the screwdriver it runs perfectly except that sometimes when you leave the engine running, put the brake on and turn off the PTO as soon as you open the control arms to get off to pick up something in your way it will stall. We have disconnected the seat switch. Could the switches in the control arms cause the ignition to not send voltage to the starter? I also noticed that someone years ago has "updated" the starting system with 2 relays. I don't know the background here but there must have been a good reason for adding the two relays instead of keeping it original. They also added a 30 amp inline fuse. I was also thinking that maybe one of these relays are bad?

Thanks for any suggestions and help. We already took it to a grasshopper dealer for repair and paid the big bucks. They had it for two months did a couple things and it worked for about two weeks and started doing exactly the same thing it was doing before we took it in.

I bought a spare PTO on ebay for less than $20. Last year my mower wouldn't start. I couldn't figure it out. I installed the new PTO and it started right up. I'm not sure how to test one.