How to change the oil in a ride-on mower

In order to keep the engine of a ride-on mower running smoothly, it needs to be properly lubricated. This is achieved by sending oil around all the mechanical components of the mower via an oil pump driven by the engine. Engine oil is a golden amber colour when new but becomes black and tacky after several hours of use.

Depending on the manufacturer's recommendations, it is generally necessary to replace this oil every 25-50 hours of operation after which point the oil loses its ability to coat and lubricate components correctly. The technique and process can vary between models, but let's take a look at the basic steps you need to follow to change mower oil the right way.

Quick tip: if you have to change the oil from above, invest in a manual or battery-powered oil transfer pump. A handy, low-cost accessory, a transfer pump is inserted into the filler hole to make the process of changing oil much easier. This type of tool is also ideal for preventing oil spills in the surroundng area.

Steps

1. Drain the mower oil and replace the oil filter

2. Replace the drain plug and top up the engine oil

3. Check and adjust the oil level

4. Grease the mower for winter storage

• First of all, if you are changing the oil on a cold engine, it is best to run the engine for a few minutes to heat up and liquify the oil which will help it to flow better.

• Next, take the ride-on mower to a clear area that is easy to clean up. You do not need to raise the mower; it must be sitting flat. If you have a bit of sand or sawdust lying around, spread a bit where you expect the oil to spill to make cleaning up much easier.

• Identify the drain plug under the mower and place a container below the cap. Unscrew the cap using a suitable spanner.

• Take the time to let the old oil drain out into the container.

• Identify the oil filter and using an oil filter wrench to loosen it. Finish unscrewing the oil filter by hand. There may be a bit of old oil left in the filter. Use a small container to collect the remaining oil.

• Fit a new oil filter taking care to oil the washer to prevent it from sticking to the surrounding surface.

• Replace the drain plug. If the copper washer is worn or flattened, replace it.

• Unscrew the fill cap and pour some new oil in according to the manufacturer's recommendations (SAE 30 4 stroke oil, for example).

• Extract the dipstick and clean it with a cloth, then use it to check the oil level. A dipstick has two lines: the minimum level and the maximum level. You should aim for the maximum level.

• Turn on the engine for a few minutes.

• Check the oil level again.

• Adjust if nececesary since the oil filter will absorb a small amount of oil.

• If you have put in too much oil, drain excess using a transfer pump. Putting too much oil in an engine will cause it to overheat while not putting enough will mean the moving parts won't be correctly lubricated and may break.

• Replace the fill cap once you are done.

In addition to changing the oil regularly, it is recommended to grease any parts of the mower that are required to move a lot. This is especially important before winter storage. Generally speaking, the product manual should identify the locations of the parts that need to be greased.

• Take a grease gun or pump filled with suitable grease cartridges.

• Place the end of the gun onto the parts you want to grease and press the trigger until the part is greased.

• Repeat the process for all parts that require greasing. Some machines do not require greasing since the joints have been coated with a long-lasting grease by the manufacturer.

• Check that all stationary parts are clean. If you run into any issues, spray some penetrating oil to loosen any components that are stuck or causing friction.

All waste (old oil, clothes, dirty sand, containers) must be brought to the appropriate recycling facility.

Required skills

No particular skills required beyond following the manufacturer's recommendations. The location of the parts required to change mower oil can differ depending on the ride-on mower. Most mowers feature a drain plug, fill cap and an oil filter.

Time required

Approx. 30 mins - 1 hour

Number of people required

1 person

Tools and equipment

• Oil transfer pump (manual or powered)

• Plastic funnel

• Oil can

• Set of spanners

• Oil filter wrench

• Oil filter with rubber washer

• Container (with a spout to pour old oil into a suitable container for recycling)

• Suitable container to hold oil for recycling

• Copper drain plug washer

• Grease gun

• Grease cartridge

• Mower oil as recommended by the mower manufacturer

• Penetrating oil

• Cloths

Safety and workwear

• Protective gloves

• Safety goggles

• Safety shoes

• Boiler suits

Please note: this is a non-exhaustive list; be sure to match your personal protective equipment to the job at hand.

More information on lawnmowers

• Lawnmower buying guide

• Electric lawnmower buying guide

• Petrol lawnmower buying guide

• How to clean your lawnmower

• How to change your lawnmower oil

• How to set up your robot lawnmower