Generator Maintenance

 June 2, 2021      Jeff Rosenblum

Generators require maintenance every year. Having it maintained can ensure a long life and problem free operation. Generators are designed to run in harsh conditions and must start at a moments notice. That’s why having it regularly maintained is so important. The maintenance intervals are to change the oil, filter and adjust the valve lash (excludes units equipped with hydraulic lifters) after the first 25 hours of operation. It is then recommended to change the oil annually or every 200 hours whichever comes first.

The first thing recommended is to run the generator (put in in manual mode) prior to starting the maintenance. This does two things; (1) it proves that the generator is operational so the maintenance can continue and not turn into a diagnostic and (2) it gets the oil up to temperature and allows it to drain faster. Running the generator also stirs up any debris and aids in removal during the oil change. Once the generator is up to temperature (about 20 minutes) shut it off and Remove the drain plug from the drain hose. Drain the oil into a container. It helps to remove the fill cap or dipstick to allow air in as the oil drains out. Once the oil is fully drained, remove the oil filter. A catch pan under the oil filter will keep it from making a mess. With the oil filter removed now reinstall the drain plug and install a new oil filter. A bit of oil on the filter gasket will help it spin on easier and keep the gasket from binding. Now add in the appropriate amount of oil.

Next is to replace the spark plugs. Remove the plug wire and loosen the plug with a spark plug wrench. It is recommended that you “read” the spark plugs. This means visually inspecting them for their condition. They should be a dull grey or tan color. If you notice any heavy soot or oily residue this may indicate a potential issue.

The next step is to replace the air filter. The air filter is in the airbox. This is on top of the generator for larger models and near the battery box on smaller units. Remove, and replace the air filter and close the air box.

Once this is done simulate a power outage by opening the main disconnect to the house and observe operation. The generator should start up and the transfer switch should transfer power automatically. This final step confirms proper operation of the transfer switch and the starting function of the generator. By performing this maintenance as necessary, you can expect proper operation from your generator when you need it the most.

As always if you need any additional help please call the Famous Supply HVAC Tech Department at 800-362-8230.

Jeff Rosenblum 
Technical Support
22 Years Industry Experience
Cell (330) 962-2491
[email protected]