the oil presure and other dial gauges are optinal, fuel pump has a electric, fuel shut off..like all moden ish disels........igntion swithc..works as thus...power to it from battery,,,,,wen switched to 1 ..elect allowed to field wire on altnatoer small wire..ok .......elec also goes to solinoid fuel shut valve on pump...which is energised and openes to allow fuel to enter the fuel injecton pump.......the 3rd postion on the igntion is the start only postion...when moved to here ......eec is allowed to run to the startr ....the start solinoid on the strater closes ...which throws in the main switch to let the elec turn the starter...
you havnt said if its a startter alternator?
thee are soe out there that do two jobs..during stater its a starter wen running it converts to a alternator
bob
May 2015