What is the resistance (ohms) of the probe?
Ohms vary by temperature. Please see the "Specifications" tab on this web page for the Ohms breakdown by temperature.
Does the Rochester 3080-37 oil temp probe come with the washer, nut and gasket?
The Rochester 3080-37 oil temp probe does come with the washer, nut and gasket.
Does this probe operate on 12 and 24 volt systems?
Power is not connected to the Rochester oil temperature probe (3080-37) and therefore the voltage of your system is not a factor.
Is this Rochester 3080-37 oil temp probe FAA/PMA approved and does it replace P/N S2335-1?
This unit does not come with FAA/PMA approval, but is the same make and model, and used for the same engine applications in experimental aircraft.