Hydraulic oil is the lifeblood of your log splitter. It supplies the power needed to drive the splitting ram through tough logs. If the oil level’s too low or it’s dirty, you’ll notice reduced splitting force and a lot more strain on the pump. Keeping your hydraulic oil clean and topped up prevents breakdowns and extends the machine’s life.
Signs You Need an Oil Check
If the splitter suddenly loses power, starts making odd noises, or the ram moves more slowly than usual, it could be an oil issue. You might also spot small leaks around hoses or fittings. Even if you don’t see immediate problems, it’s wise to check the oil routinely—most manufacturers recommend doing this every time you use the splitter or at least once a month.
Getting Ready to Inspect the Oil
Turn off the log splitter and let it cool. For gas models, remove the spark plug wire to ensure it can’t start accidentally. Wipe down the area around the reservoir cap or dipstick to keep dirt out. If your splitter has a dipstick, it’s usually a part of the fill cap. Pull it out and wipe it clean before dipping it back in for a reading.
Checking the Oil Level and Condition
Look for the recommended fluid level on the dipstick or the tank’s sight gauge. If it’s below the mark, you’ll need to add hydraulic oil specified by the splitter’s manual. Take a closer look at the fluid’s color, too. Fresh oil should be clear or slightly amber. If it looks milky or smells burnt, it’s time for a change.
How to Drain and Replace
Find the drain plug at the bottom of the hydraulic reservoir—check your manual if you’re unsure. Position a container that can hold all the old fluid and carefully remove the plug. Let the oil drain completely. Watch out for any metal shavings or sludge that may indicate internal wear. Reinstall the drain plug once it’s empty.
Refilling the System
Add fresh hydraulic oil slowly, checking the level every so often. Remember, it expands when heated, so don’t overfill. If your splitter has filters, now’s a good time to replace them. Start the engine or power source briefly to circulate the new oil, then shut it off. Recheck the level and top up if needed.
Final Check and Cleanup
Run the ram a few times with no load. Listen for unusual noises and make sure the movement is smooth. Keep an eye on hoses, fittings, and the reservoir area for leaks. Wipe away any spills and secure the oil cap. Proper disposal of used hydraulic oil is a must—don’t just dump it. Take it to a recycling center or an auto parts store that accepts old fluids.
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