570LXT Loader Landscaper Tach trouble shooting and service manual ???

[bingles]

hello since I probably wont find a service book for the 570LXT Loader Landscaper, does anyone know the correct voltages sent to the tach? With the wires unpluged and tractor running I was get something like .5 volts @idle and then it went up when I pressed the gas peddle.
That seems about right however I don't have a manual to know, does anyone know if this is correct? Also can I ohm out the gauge its self to see if that's the problem? Also does anyone have the Tach troubleshooting page of the service manual?
570LXT Loader Landscaper Construction king

Or does anyone know how to get a service manual, The case website wants like $240 for a pdf ver... thats seems really crazy for this old junker. All my John Deere tractor service manuals where really cheap and most were free.
Any help would be great I just want to trouble shoot his tach and check out few other things and also a parts manual for replacement parts. pictures would be nice, the case website doesnt show picture for parts just the part name. kinda lame if you ask me.

Thanks and feel free to PM me if you like
Thanks again For your time
Brian

 

[bingles]

Does anyone know if the listed voltage above is correct with the Tach unpluged and reading off the wire?
Also where does that voltage come from is it pulled off the ALternator or a sensor on the Motor?

Thanks
Brian

 

[bingles]

Can someone at least point me in the right direction?