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How to drain oil from a Briggs and Stratton lawnmower, step by step

When storing your Briggs mower at the end of the season, it is good to empty the mower gas tank. It inhibits oil residues from clogging up in the container over a long period. Moreover, the fuel is also present inside the carburetor and the fuel lines, which may deteriorate over time. If your Briggs and Stratton lawnmower refuses to start or is hesitating, there is a high chance that bad gasoline or a bad spark plug may be the cause. You should also change the mower’s oil at least once per season for a prolonged mower life. Hence, draining oil from your lawnmower is a necessary skill for those who take lawnmower maintenance seriously.  

Motor oil is essential for a lawnmower to function correctly. Lubrication is necessary for most moving parts of the engine. Over time the oil will contain more and more small particles from the engine internals. If you use old oil, it can increase the wear and tear of the engine. And if not changed at all, it can even ruin your lawnmower engine. This article explains how to drain and replace the oil in your Briggs and Stratton Lawnmower.

How to drain oil from a Briggs and Stratton lawnmower, step by step:

  • Step 1: Get all the needed tools
  • Step 2: Park your lawnmower on a plane surface
  • Step 3: Disconnect the spark plug cables
  • Step 4: If your mower has a drain valve and dipstick, use a drain tube
  • Step 5: If your Briggs and Stratton lawnmower has an oil drain plug, unscrew it
  • Step 6: Use an air pump to remove the last oil
  • Step 7: Replace the oil and the oil filter

Drain the oil from your Briggs and Stratton Lawnmower

Draining oil is not a difficult job. It should take you around 30min. It is advisable to change your lawnmower’s oil once per season.

● Step 1: Get all the needed tools

One of the tools you need for draining oil is a drain tank that you have to place beneath the lawnmower. Locate the position of the oil filter and nut that you have to open. A drain pan is a small metal pan with raised edges to facilitate the old oil without making a mess. Next, you will need a drain tube. This is a simple plastic tube and can be found at many stores that sell lawnmower supplies. To loosen the oil filter, you need a strap wrench. Of course, you also need a new oil and a replacement oil filter. Check your Briggs and Stratton manual for better insight and visual displays.

● Step 2: Park your lawnmower on the plane surface

Place the mower on an even hard surface to permit easy access to the underside. Please do not tip the lawnmower on its side, as oil can run from the reservoir to other parts of the engine. Use the parking brakes of the lawnmower to keep it from moving.

Tip: Let your mower run in a well-ventilated area for a few minutes before all this procedure. This will warm up the engine and oil, which will lessen the viscosity of the oil. Removing the oil, therefore, becomes easy. But be careful not to let it run too long, as the oil can be really hot.

● Step 3: Disconnect the spark plug cables

As a safety step, it is good to disconnect the spark plug cables. That will ensure that the engine can not unintentionally start.

● Step 4: If your Briggs and Stratton lawnmower has a drain valve and dipstick

If your Briggs mower has an oil dipstick, it will most likely be present under the hood. Mostly, modern machines have them. They mostly have a drain valve on the side of the mower. Remove the dash cover by loosening the fastener. Remove the drain valve cap. Push the drain tube onto the valve, turn it clockwise, and clicks. Place the drain container beneath. Pull the valve to start draining the oil.

Doing this, take out the oil dipstick to develop a channel of air from top to bottom. While oil is being drained, make sure that no debris falls into the oil tank. So please work in a clean environment.

After the oil is removed, fasten the dash cover on this site. On the opposite side of the tank base, you will find the oil valve. You might have to remove the side cover to see it. With the help of a strap wrench, turn it anti-clockwise to loosen it. You always have to replace the oil filter whenever you change the oil. This is because of the impurities that reside there.

● Step 5: If your Briggs and Stratton lawnmower has an oil drain plug

If your lawnmower is a smaller or an older Briggs and Stratton type, you should use this step. Raise the mower to a suitable level and place the drain bed right beneath the oil tank, more precisely, the nut. You can unscrew the nut with anti-clockwise twists. The oil filter will be present next to it. Use a strap wrench to remove it. Often you have to use some force to open the oil drain plug, so your hands are likely to get messy by the leaking oil. In that case, it is a good idea to wear some gloves.

● Step 6: Use an air pump to remove the last oil

You can use an air pump to ensure you remove all the oil. The air pressure will push the last oil droplets out. If the air is free from moisture, this does not have any adverse side effects, and it is useful for aerating the channels. Using an air pump is an additional step. If you do not own one, you can also let the oil drip out for some time to ensure you remove as much oil as possible.

● Step 7: Replace the oil and the oil filter

Finally, it is always preferable to lubricate the new oil filter by some new oil moisturizing its seal. Tighten it tightly by rotating it clockwise. Drop the dipstick and add fresh oil. Engage the spark plug, turn the ignition on and let the engine warm up the new oil. Let the oil flow in the channels while you check other connections.

Some safety measures:

Maintaining your lawnmower is important to keep it working for many years. But always give attention to safety. Some precautionary measures are:

1. Work in a Ventilated area: In a constrained or enclosed space, do not try to start a lawnmower. The carbon monoxide gas, which exists in exhaust fumes, is odorless, colorless but very poisonous, toxic, and is really bad for your health. Ideally, you should only test your lawnmower’s engine outdoor. If you run the lawnmower in a garage or workshop, it should only be done for a short time. And ensure that the location is well ventilated, or keep the doors and windows open.

2. Remove the battery and spark plug cables: Before working on your lawnmower engine or the blades, disconnect the battery connections and spark plug cables. This way, you know that it is impossible that the engine unintentionally can start. Or that a short circuit can ruin your battery and electrical system.

Frequently asked questions:

1. What kind of oil do you put in a lawnmower?

The type of oil that you have to use depends mostly on the engine type and mower brand. Generally, the specifications are listed in the mower manual. If you can not find it, you can typically use an SAE 10W-30 oil to keep your lawnmower engine in prime condition. The digits indicate the viscosity of the oil at a suitable temperature. As your mower gets older, you might have to use a thicker oil

2. My two-stroke lawnmower engine does not have an oil reservoir or oil filter

Two-stroke engines do not have a separate oil reservoir. Oil is added to the gas. In a two-stroke engine, the crankcase is exposed to the air/fuel mixture, and the oil in the gas makes sure that the parts are lubricated. This is not the case in a four-stroke engine, and a separate oil supply is needed.

3. Can I use another container to gather the oil if I don’t have a drain pan?

You can use any container to drain your mower oil. Make sure that it fits under the lawnmower. A drain pan is designed to help collect the oil without creating a mess and is such that it fits perfectly under the lawnmower. It is also made from a rigid material, so it has a long life span and can deal with hotter oil. But you can use something like a simple jug or pot to collect the oil.

Final remarks:

Draining oil from your lawnmower is not a difficult or time-consuming job. Changing your mower oil is an important maintenance step to keep your mower working for many years. The oil will get dirtier over time, and small parts from the engine will get into it. The exact steps to drain oil will depend on the Briggs and Stratton lawnmower type you have. After draining the oil, you can replace it with new oil, but do not forget to fit a new oil filter.