This seems to be the place for Groundsmasters on the forum, so I will join in.
I picked up a very old Groundsmaster 72 a few weeks ago. I wanted one to mow around my orchard and several acres of lawn.
Model 30782 Serial 10127. I am thinking early 80's but am not exactly sure of the year.
It's in really decent shape for the age. About 3k hours on it. Deck is in excellent shape and overall seems like it has been fairly well maintained.
I have several things I am going to do immediately. Replace all the fluids, get everything adjusted properly. Replace the extremely old hard tires. I have lots of hills, so I am going with a slightly more aggressive Carlisle tire to minimize slipping.
The electric fuel pump is not working. So, I am going to ditch the ancient Stanadyne water separator and inline fuel filters and go with a spin on water/filter combo and replace the fuel pump to simplify the fuel system.
So far it seems to be an extremely straightforward and easily worked on machine.
My immediate repair on it is the fuel solenoid. The solenoid apparently went out, so instead of replacing it, someone cut the wires on it and it was being used as a kill switch via the manual plunger. That does not work for me.
Which leads me a to question.
I bought a new solenoid. And in trying to get it working led me to the electrical system. It has been hacked on a bit over the last 40 years. No surprise there. It's not bad, but I think someone with minimal electrical knowledge tried to troubleshoot the solenoid issue which led to some wire cutting.
Anyway, going through the manual it shows that the Control Module needs replaced as I do not have voltage from "both" of the blue wires leading from it. Flowchart leads to replace module if that condition exists.
My real question here is this. Looking at the wiring diagrams, it seems the Control Module controls the fuel solenoid and somehow connects back to the ammeter and glow plugs. That is the function I do not understand.
Does the control module apply momentary voltage to the solenoid at shut down? Solenoid is a normally open condition, so would engage to kill engine as opposed to a normally closed solenoid which required voltage to remain open during operation.
And, what is it doing with the ammeter and glow plugs?
My immediate solution it seems is to ditch the control module and use a momentary push button on the panel to close the solenoid to shut the machine off. Module is a discontinued part and I honestly can't see searching around and trying to source a used one if it only exists to operate a solenoid. So, unless I am missing something else that the module does, it seems an overly complicated solution to a simple function.
My plan with the machine is to rebuild it over the winter. I really like to take things that are old and make them work like they did when new. I am a sucker for punishment for the most part.
I will take some better pictures later. It's jammed in the shop currently beside my tractor, so isn't super accessible for photo ops.
