How to Test the Low Oil Pressure Switch on a Generator

Gasoline generators create an A/C current to create power that can be connected with a plug to a variety of different household items and power tools. Once the engine has started, the crankshaft turns a large stator inside of an armature creating electricity; which is then sent to the receptacles. The engine has an oil sensor switch that will not allow the engine to start if the oil drops below a certain level, causing the internal pressure to drop.

Step 1

Place the generator on a hard, level surface. Remove the oil dipstick near the bottom of the engine and check the oil level; add oil if needed.

Step 2

Disconnect the wire coming off the engine oil switch. The oil switch wire will exit from the engine, near the starter; follow the wire to the wire harness.

Step 3

Turn on the ohmmeter and set the ohmmeter to the lowest ohms setting. Place the positive lead from the ohmmeter into the connector on the engine oil switch; place the negative lead from the ohmmeter to a suitable ground on the engine. There should be no continuity.

Step 4

Drain out all the engine oil and check the continuity once again; there should be no more than 2 ohms of resistance. If either reading differs, replace the switch.

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