Janine

The oil gage is simplest - you can test with compressed air. Use regulator and start at zero and crank regulator up. Have separate gage to compare to they should agree +/- 5psi or so.

Power for testing can be supplied with small batteries.

Have switch so you can turn on and off quick. Close sitch and see if goes right way - if not open switch. One or two second wrong should not hurt.

Temperature would be best done with sensor in cup of hot water with thermometer. Watch out for polarity.

Ammeter check meter to determine if it is to be connected in the line or if it is a 50 mV unit requiring shunt. You will need a load. Go to Radio shack and get a 5 and one ohm resistor. Connect resistor in series with meter - if line type. If shunt connect shunt inseries and connect the Output leads to meter.

Dan Bentler