WanaBFarmer
New member
My Workmaster 55 became difficult to start about 3 weeks ago and I am trying to troubleshoot it.
I need a copy of the wiring diagram to troubleshoot it further to figure out the specific component that is the problem.
I've narrowed it down to the fuel shut off solenoid does not reliably open when cranking to start.
So far:
I've had the fuel shut off solenoid off and it operates fine on 12 v.
I jumpered the solenoid straight to the battery and the tractor will start every time.
Given the tractor operates normally once started and with jumper removed I can't see any of the safety switches being the problem.
The battery voltage drops to 10.7 V when cranking but I would consider this normal and it is a new battery.
But
My original guess was the key switch was faulty and the power to the "fuel control unit" would drop out when turned to the cranking position but it doesnt drop out completely.
I think the fuel control unit is just a fancy name for the "relay logic" that looks at all the safety switches and then powers the fuel shut off solenoid.
The supply wire voltage at the key switch is only 9.6 V approx and going out is only 8.8 V approx when cranking.
My guess is that is too low for the "fuel control unit" or the fuel shut off solenoid to operate properly.
Once the tractor is running the key switch in and out see 13 to 14 V.
I need the wiring diagram to trace all the connections and relays/devices to go further with the troubleshooting.
Thanks
I need a copy of the wiring diagram to troubleshoot it further to figure out the specific component that is the problem.
I've narrowed it down to the fuel shut off solenoid does not reliably open when cranking to start.
So far:
I've had the fuel shut off solenoid off and it operates fine on 12 v.
I jumpered the solenoid straight to the battery and the tractor will start every time.
Given the tractor operates normally once started and with jumper removed I can't see any of the safety switches being the problem.
The battery voltage drops to 10.7 V when cranking but I would consider this normal and it is a new battery.
But
My original guess was the key switch was faulty and the power to the "fuel control unit" would drop out when turned to the cranking position but it doesnt drop out completely.
I think the fuel control unit is just a fancy name for the "relay logic" that looks at all the safety switches and then powers the fuel shut off solenoid.
The supply wire voltage at the key switch is only 9.6 V approx and going out is only 8.8 V approx when cranking.
My guess is that is too low for the "fuel control unit" or the fuel shut off solenoid to operate properly.
Once the tractor is running the key switch in and out see 13 to 14 V.
I need the wiring diagram to trace all the connections and relays/devices to go further with the troubleshooting.
Thanks
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