generator fan wont run

[davidbrady]

Al,

If the genny doesn't stay running it can be either of 4 things three of which are safety switches.

The safety switches are the:
1) oil pressure switch which closes when pressure builds,
2) water temperature switch which closes if temperature gets too high, and
3) water level switch which closes if radiator level gets too low.

The fourth item which can prevent the engine from running is a faulty run solenoid.

You can take (2) and (3) out of the loop by disconnecting each. Pull the terminal off the water temp switch and disconnect the water level switch. If it doesn't stay running then the problem is either the oil pressure switch or the run solenoid.

To test the run solenoid disconnect the blue and gray wires going to the solenoid. Apply 12V to each simultaneously. The run solenoid should retract, now remove power from the blue and leave it remaining on the gray. If the solenoid stays retracted then the run solenoid is good.

If all this checks out then the problem is the oil pressure switch.