Essential Generator Oil Change and Maintenance Tips

Most people never take time to study their generator owner’s manual perhaps because they are in a hurry to get the lights back on. However, it is important to read it carefully in order to understand how to properly maintain your generator, especially during emergencies. Storm-induced power outages can last for weeks or even months which may require you to run your generator for many hours. This works up your machine hence the need to consistently maintain the generator to ensure that it is always in good shape. Regular maintenance of your generator involves the following:

  • Checking the oil frequently
  • Using correct weight oil
  • Changing the spark plug
  • Maintaining air and oil filter
  • Filling with the proper fuel
  • Cleaning the engine
  • Checking the Oil

Lack of oil or a low oil level can cause severe damage to the engine especially if your generator lacks the low-oil shutdown feature. If your generator is not performing as well as it should, check the oil first before anything else. Most generator engines unlike those used in cars are air-cooled hence they tend to burn through oil at a faster rate when conditions are extreme.

How to Maintain the Air Filter

Emergency best practices require that you have a clean air filter on hand as this ensures that the generator runs smoothly even in extreme conditions. While it is often important to replace the air filter from time to time, you should clean the current air filter by washing it in soapy water and drying it gently with a clean piece of cloth but do this with caution to avoid tearing your air filter thus rendering it defective. Whether the air filter looks dirty or not, clean it after every 100 hours and ensure that you change it on a monthly basis.

How to Maintain the Spark Plug

It is also important to inspect your spark plug after a long period of use. You may need to do this more often during extreme conditions when chances of spark plug failure are higher. Take out the spark plug for inspection after the unit has cooled off as this also helps to relieve the engine after heavy duty running. A dirty plug should be cleaned lightly using a wire brush while also checking the gap for optimum performance. After inspecting your spark plug, use a torque wrench to replace it. When replacing the spark plug, ensure that you do not overtighten it as this could strip the threads or even worse, destroy the porcelain insulator causing irreparable damage to the engine. After every 100 hours of use, inspect your spark plugs for excessive carbon buildup, oil residue or damage. If the plug has cracked porcelain, replace it immediately.

Fueling Your Generator

Some generators may get severely damaged if they run out of gas since while they are coming to a stop, they will put out power and the coil’s magnetic field may get drained by the electrical load in the house. The generator will later run fine but it will not be generating any power which will eventually cost you time and money to repair. Always keep the generator’s tank filled and ensure that the electrical load is removed before shut down. When running your generator after a long while, drain the old fuel with a hand pump and run the carburetor dry.

Old fuel could be your worst nightmare so make sure that you reload with fresh gas as stale fuel will cause starting problems. Always empty the tank as well as the carburetor after an extended power outage. But before draining your carburetor, allow the engine to cool off. Alternatively, empty the tank before running the generator until it runs out of gas. Avoid refilling in dusty conditions as dirty fuel could also damage your generator. Inspect and clean the fuel strainer found in the fill port of your generator’s fuel tank at least once every month. If it is torn, replace it.

Read The Manual

A lot of accurate information can be found on the owner’s manual regarding the proper oil maintenance procedures for your generator. In most cases, the manufacturer will normally list the type of generator oil required as well as other important procedures to follow. Generally, a generator that is running in extremely cold temperatures needs a lower-viscosity oil so that it can start without much trouble. High-viscosity oil should be used in generators that are running in extremely hot temperatures. Viscosity is basically the oil thickness at a given temperature.

Larger generators are equipped with oil filters that need to be replaced regularly especially during prolonged power outages. Check the owner’s manual for recommendations but it is recommended that you replace the oil filter at least once in course of a long power failure. For new generators, it is advisable to change the oil after 20 hours of use as this helps to remove assembly lube as well as the metallic particles formed during the break-in period. After this, you can change the oil after every 100 hours.

Cleaning the Engine

Cleaning the engine is an important maintenance practice since besides helping to remove potentially harmful dirt, it also allows you to identify service concerns on your generator. Avoid using a pressure washer to clean the engine as this may harm the generator. It is advisable to blow off dust particles using an air supply and then use a clean piece of cloth with degreaser to clean any excess grease or dirt. Once your equipment is thoroughly cleaned and dry, look out for any oil leaks and if you spot one, tighten or replace the parts causing the leak immediately.

A clean engine will also help you to spot loose parts and obvious damage. Any loose parts should be properly tightened as they could cause vibrations that can potentially damage other parts of the generator.


These generator oil change and maintenance tips should help you maintain your generator during a long power outage and extreme conditions to keep it in the best shape possible.