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How to Change Oil in a Lawnmower

One fine day you plan to give your grass a nice trim. It’s been a while now after you’ve purchased your Lawn Mower, and you realize it is the right time to perform some routine maintenance. The first thing that comes into your mind after hearing the word maintenance is an oil change. You haven’t changed your oil before, and you aren’t sure if you should do it yourself or take your mower to a mechanic who might charge extra bucks. If you’re a DIY kind of a guy who is looking online for how to change the oil in a lawnmower, then you’ve come to the right place.

Lubricant oil is often used for reducing wear and tear between engine parts. This process enhances the engine service life. During constant operation, the oil quality reduces. Therefore, it is mandatory to change your oil after 50 hours of operation (or once every season). You might need to change the oil after 25 hours of operation (twice every season) in case of frequent use. For changing the lawnmower oil, you should follow these steps:

How to Change Oil in a Lawnmower:

  1. Warm up your engine and get the things you need for the job
  2. Drain the used oil by choosing the appropriate drainage method and following the safety precautions
  3. Fill the oil tank with the right kind of lubricant for your lawnmower to the desired level
  4. Allow the oil to settle and clean your worksite

Suppose you’re looking for an in-depth guide to the above steps. In that case, you should stay tuned to this article as we provide you with the information you are searching for in a user-friendly and straightforward language.

Steps to Change Lawnmower Oil:

You should follow the steps below that provide you with a detailed procedure and the precautionary measures to be taken care of while making an oil change.

1) Preparation for an oil change:

Before carrying out the oil change, you should ensure that you take the necessary precautionary measures:

● Step 1: Run your engine for a while:

Start your engine and keep it running for a while (preferably for 15 minutes). This warming up of your engine will, in turn, warm up the oil. Resultantly, the oil moves more freely, and the draining process becomes easier.

● Step 2: Clean the oil fill area:

The oil cap often gets a lot of debris from the outside. Also, the area around it, being oily, often attracts dirt from the atmosphere. It would be best if you used a towel to clean that area gently along with the fuel cap to remove the debris.

● Step 3: Keep your kit ready:

Depending on the process of your oil drainage, you should keep your equipment ready. If you want to remove the oil using the Siphon method, you should keep the siphon pump ready. In most cases, the oil is drained using the tilt method, so for that, you should keep a pan for pouring the drained oil. You should also purchase the requisite oil grade for your machine by thoroughly undergoing your user’s manual. Most lawnmowers use SAE 30 detergent oils. However, you should only use the one that is recommended by your manufacturer.

You can watch this video to get a better understanding of the above steps:

2) Drainage of the used oil:

The oil drainage can be carried out either by using the siphon method or the tilt method. However, before you drain the oil, you should first follow the safety precautions as given below:

● Step 1: Remove your spark plug:

The spark plug needs to be disengaged during this process. This step ensures that your safety isn’t compromised since spark plug connected might result in the engine accidentally starting up (most probably when the blades are rotated). Hence, disconnecting the spark plug provides you with an additional safety layer.

● Step 2: Secure the fuel cap:

It is preferred that you thoroughly drain your gasoline before doing the oil change, especially during the tilt method. If that is not possible, it is also good to use a sandwich bag underneath your cap and then tighten it so that there isn’t any chance of the oil leaking from the cap.

● Step 3: Perform oil drainage:

– Tilt method:

In this method, you tilt tour lawnmower towards the side so that your air filter points upward (this prevents the fuel from entering into the air filter). Afterward, you open the oil cap and allow all the oil to be drained into the pan. Make sure you do not make contact with the hot oil that can be damaging for your skin.

– Using the oil drain plug:

Not all lawn mowers are equipped with an oil drain plug. You should consult your user’s manual to identify the oil drain plug’s location in your machine. Generally, it is located below the deck of the lawnmowers. Again, it would help if you tilted the mower to its side to see the plug and remove any debris present around. Then, use a hand tool to open the cap (with your mower placed upright) and allow the oil to be drained into a pan.

– Siphon method:

During this method, a siphon pump is put into use. These pumps drain the oil into an in-built tank from where it can later be drained off. You should manually suck the oil out by pushing/pulling the piston. It is a much cleaner and efficient way of oil drainage as it results in no oil spills in the work area.

Here’s a quick guide in this video:

3) Addition of fresh oil:

After you have purchased the right kind of oil for your lawnmower, the next step is adding fresh oil into the oil tank. Place your mower into an upright position and keep adding oil in small quantities. It would be best if you kept checking your dipstick every time to visualize the oil level. Keep adding the oil until the desired level is achieved.

4) Cleaning up the work area:

After you’ve added the fresh oil, it is recommended to keep your mower upright for 5 minutes and let the oil settle. Recheck the oil level and replace your oil dipstick. Afterward, reconnect your spark plug and remove the sandwich bag around the fuel cap. Clean the oil spilled on your floor. It is advisable to take your drained oil to a recycling dealer.

You can refer to this video below to watch a practical demonstration of this process:

Related Questions:

1) What happens if you do not change the oil in a lawnmower?

If an oil change is not done for some time, then the engine’s wear rate increases. Also, most lawnmowers do not have an oil filter. As a result, the quality of the oil deteriorates very quickly. Moreover, the oil is responsible for the cooling of the engine apart from the air-cooling. The engine’s life fall’s short of its manufacturer predicted lifespan. Hence, it’s positively not recommended to neglect the oil changes in lawnmowers.

2) Can you use car oil in a lawnmower?

SAE 30 motor oil is commonly used in a lawnmower. Some machines may use 10W-30 or 10W-40 oils as recommended by their user’s manual. These oil types are often used in vehicles. Hence, they can be used in lawnmowers.

3) What is an SAE 30 oil?

SAE 30 is a motor oil that has rated a viscosity value of 30 as rated by the Society of Automotive Engineers (SAE). These ratings are generally from 0 to 50. The viscosity refers to the thickness of the oil or its ability to flow. Thinner oils (with low viscosity) give better performance in cold weather. In contrast, thick oils are used when the temperatures are high. SAE 30 is a single grade oil that is thicker than lower grades. It is typically used in small air-cooled engines such as in lawnmowers, chainsaws. Most motor oils are multi-grade, i.e., they can perform in all seasons.

4) Is SAE 30 the same as 10W-30?

10W-30 indicates that the oil has a viscosity of 10W when the engine is cold and 30 when it is hot. It would help if you considered factors such as temperature while making this choice. SAE-30 is a single grade oil that is suitable in conditions where its high temperature and the variation isn’t significant. Whereas, if your weather keeps on varying, then you may use 10W-30. It also improves cold-starting at lower temperatures as compared to SAE-30. Hence, if you’re living in moderate or milder climates, then using SAE 30 or 10W-30 won’t make much difference regarding engine performance.

5) Is a lawnmower engine 2-stroke or 4-stroke?

Lawnmower engines come with both designs, i.e., 2-stroke as well as 4-stroke. In a 2-stroke design, the entire cycle of combustion and power is completed in the crankshaft revolution. In a 4-stroke, it takes two revolutions of the crankshaft for the whole cycle to complete.

In the case of 2-stroke engines, oil is mixed with the gasoline as there is no separate reservoir. In comparison, 4-stroke engines require an oil reservoir to lubricate the connecting rods and crankshafts thoroughly.

Final Remarks:

Oil changes are significant at the right time as they ensure that your engine components undergo minimum wear and tear. Also, the overuse of low-quality oil for a long time can result in engine servicing that might be costly. Hence, you should always keep a check on the working pattern of your lawnmower. It is better to replace oil at the beginning of every season. In the case of overuse, you might need an oil change in the middle of the season. Ensure that you use the right oil type and always follow the safety precautions while replacing the oil. “Prevention is always better than the cure” is the principle you should go about whether it’s maintaining yourself, your car, or your lawnmower.