How to Change the Oil in a Log Splitter or Pump Engine

Why Regular Oil Changes Matter

Oil keeps your engine running smoothly. Over time, oil breaks down and gets dirty from heat, dust, and debris. Changing the oil on your log splitter or pump engine is one of the most important maintenance tasks you can do. Regular oil changes help your engine last longer and work better.

When oil gets old and thick, it doesn't flow as easily through your engine. This means your engine has to work harder, which causes more wear and tear. Fresh oil protects all the moving parts inside your engine and keeps everything running at its best. By changing your oil on schedule, you're investing in the life of your equipment.

What You'll Need

Before you start, gather these items:

• New oil (check your engine manual for the correct type and amount)
• An oil drain pan or bucket
• A wrench or socket that fits your drain plug
• A new oil filter (if your engine has one)
• An oil filter wrench (if needed)
• Rags or paper towels
• A funnel
• Safety glasses or eye protection
• Work gloves (optional but helpful)

Having everything ready before you start makes the job go faster and smoother. You won't have to stop halfway through to look for a tool. Most of these items are inexpensive and worth keeping on hand for future maintenance tasks.

Step 1: Prepare Your Engine

Let your engine cool down completely before you begin. A warm engine is easier to drain, but a hot engine can burn you. Wait at least 30 minutes after running it. This gives the oil time to cool down so you can handle it safely without risking burns.

Place your engine on a flat, level surface. This helps you drain the oil completely and keeps spills to a minimum. If your engine is tilted, some old oil will stay inside and mix with your new oil, reducing its effectiveness. Make sure the ground beneath your engine is clean and free of debris. Lay down cardboard or newspaper to catch any spills and make cleanup easier.

Step 2: Locate and Remove the Drain Plug

Find the oil drain plug on the bottom or side of your engine. Your engine manual shows you exactly where it is. If you don't have the manual, look for a bolt or plug that sticks out from the lowest part of the engine. Position your drain pan underneath the plug to catch the old oil.

Use your wrench to loosen the drain plug by turning it counterclockwise. Once it's loose enough, you can unscrew it by hand. Be careful—oil may still be warm even after cooling. Let all the old oil drain into the pan. This may take several minutes. Tip the engine slightly if needed to drain it completely. The longer you let it drain, the more old oil you'll remove.

Once the oil stops dripping, wipe the drain plug clean with a rag. Look at the metal washer or rubber gasket on the plug. If it looks cracked, flattened, or damaged, you should replace it with a new one. A worn washer can cause leaks when you reinstall the plug.

Step 3: Replace the Oil Filter (If Your Engine Has One)

Not all small engines have an oil filter, so check your manual first. If your engine does have one, it's usually a cylindrical canister located on the side of the engine. Locate it and position your drain pan underneath to catch any oil that drips out.

Use an oil filter wrench to turn the filter counterclockwise until it comes loose. Unscrew it by hand and let any remaining oil drain into the pan. Wipe the filter housing—the part where the filter screws on—clean with a rag. Remove any dirt or old gasket material.

Take your new filter and apply a thin layer of new oil to the rubber gasket (the ring) on top of the filter. This helps create a good seal. Screw the new filter on by hand until the gasket touches the housing, then turn it another three-quarter turn. Don't use the wrench to tighten it. Hand-tight is correct. Over-tightening can damage the filter and make it hard to remove next time.

Step 4: Clean and Reinstall the Drain Plug

Wipe the drain plug clean with a rag. Check the washer or gasket on the plug—if it looks damaged or worn, replace it with a new one. A fresh washer helps prevent leaks.

Screw the drain plug back in by hand first. This prevents you from cross-threading it, which can damage the engine. Once it's hand-tight, use your wrench to tighten it snugly. You want it tight enough that oil won't leak out, but not so tight that you damage the plug or the engine threads. If you over-tighten, you may crack the plug or strip the threads inside the engine, which is expensive to repair.

Step 5: Add New Oil

Place a funnel in the oil filler cap opening on top of your engine. The filler cap is usually labeled with an oil can symbol. Slowly pour in the new oil. Check your engine manual to see how much oil your engine needs. Pouring slowly prevents splashing and helps you avoid overfilling.

After adding oil, wait a minute or two for the oil to settle. Then check the oil level with the dipstick or sight glass, depending on what your engine has. Add more oil if needed until it reaches the correct level. Don't overfill—too much oil can damage your engine just as much as too little. Once you've reached the right level, replace the oil filler cap securely.

Step 6: Run Your Engine and Check

Start your engine and let it run for a few minutes. This circulates the new oil through the engine and helps the new filter fill with oil. Then turn it off and wait a few minutes for the oil to settle back down into the pan.

Check the oil level again using the dipstick or sight glass. Top it off if necessary. Look under your engine for any leaks around the drain plug or filter. If you see leaks, tighten these connections slightly. A small drip or two is normal right after an oil change, but steady leaking means something isn't tight enough. Let the engine sit for a few minutes and check again.

Key Takeaways

• Regular oil changes keep your engine running smoothly and extend its life
• Always let your engine cool before draining old oil
• Use the correct type and amount of oil for your specific engine
• Replace the drain plug washer if it looks worn or damaged
• If your engine has an oil filter, replace it at the same time you change the oil
• Check the oil level after running the engine to make sure it's correct
• Dispose of old oil responsibly at a recycling center or auto parts store

What to Do With Old Oil

Never pour old oil down a drain or into the ground. Oil is harmful to the environment and can contaminate water supplies. Take your old oil to a recycling center, auto parts store, or service station. Many places take used oil for free or for a small fee.

Some communities have special collection days for hazardous materials, including used oil. Call your local waste management facility to find out where you can drop off your old oil. Proper disposal protects the environment and is often required by law.

How Often to Change Oil

Check your engine manual for the recommended oil change schedule. Most small engines need an oil change every 50 to 100 hours of use, or at least once per season. If you use your engine heavily, you may need to change the oil more often.

Keep track of your engine's running hours if possible. Some people mark their calendar with the date of the last oil change to help them remember when it's due. Changing oil on schedule is much cheaper than repairing or replacing an engine that has been damaged by old, dirty oil.

Frequently Asked Questions

What type of oil should I use in my log splitter or pump engine?

Always check your engine manual for the correct oil type and viscosity. Most small engines use SAE 30 or SAE 10W-30 oil, but some may require different grades depending on the climate and season. Using the wrong oil can damage your engine, so it's important to follow the manufacturer's recommendation. The manual will also tell you whether to use conventional or synthetic oil.

Can I change the oil without an oil filter wrench?

If your engine has an oil filter, an oil filter wrench makes the job easier, but it's not always necessary. If the filter isn't too tight, you may be able to unscrew it by hand. You can also wrap a rubber band or old cloth around the filter to get a better grip. However, a filter wrench is inexpensive and makes the job much simpler, especially if the filter is stuck tight.

How do I know if my engine has an oil filter?

Not all small engines have oil filters. Check your engine manual to see if yours does. If you're not sure, look around the engine for a cylindrical canister about the size of a soda can. Oil filters are usually located on the side of the engine and have a drain hole at the bottom. If you don't see one, your engine probably doesn't have a filter, which is common on many log splitters and pump engines.

What happens if I overfill the oil?

Too much oil can cause your engine to smoke, run poorly, or even seize up. Excess oil can also leak out and make a mess. Always fill to the level shown on the dipstick or sight glass, not above it. If you accidentally overfill, drain some oil out until you reach the correct level.