This is something I frequently see debated online. You need to tip your mower over to do some maintenance. Maybe you want to clean some dried-on clippings from under the deck or maybe you need to change your blade. Whatever the reason, I’ve seen some pretty heated conversations with people having differing opinions on the way you should go about doing this. I can tell you from experience that there definitely is a right way and a wrong way to flip a mower over.
The answer with regard to how to tilt a lawn mower is actually very simple. The absolute best way is to tip it straight back on its back wheels. But as it’s at a 45 degree in this position, access to the underside of the deck can be tricky, which is why I like to tilt it on its side. Just make sure the carburetor and air filter are facing up.
Before You Start
Before you flip your lawn mower over, there are a few things you should always do:
- Wait Until It Cools Down – This only applies if you’ve been using it. If you have, you need to wait a while to let the engine cool down. Handling a hot mower is not the best idea!
- Take the Spark Plug Cable Off – This is the step that you’ll always want to take. Disconnect the spark plug lead from the spark plug. That way, it’s impossible for the mower to start unintentionally.
Now that you’re safe, you can get on with tipping your mower over.
How to Tilt Your Lawn Mower: The Best/Safest Way
This is not actually how I tilt my lawn mower, for reasons I’ll explain in a minute. But if you’re talking about the best way to tip a mower in terms of minimizing what can go wrong, this would be it.
And it’s really very simple. Pull the front end of your mower upward into the air, and allow the mower to rest on its back end.
Why is this the best/safest answer to the “how to tilt a lawn mower” question? Well, when tipping a mower over, the main danger is that fuel and oil can leak, but with this method, there’s virtually no chance of this. The oil will pool on the backside of the engine, nowhere near your carburetor, muffler, breather tube, valves, spark plug or piston.
So why wouldn’t I tilt my lawn mower this way when doing maintenance? That’s what you’re thinking right? (or that I’m completely stupid!).
The problem with this way of flipping the mower is access to the undercarriage. The mower is resting at a 45-degree angle. And if it’s on the ground, that means you’ll have to get on your back like a mechanic to actually work on the mower deck or blade. And for me personally, that’s not a lot of fun.
If you tilt it this way on a workbench or something similar, access is slightly easier, but I still personally find it a little awkward, which is why I don’t normally use this method myself.
How I Tilt My Lawn Mower Most of the Time
How I like to tilt my lawn mower 99% of the time when I’m doing maintenance is on its side. BUT (you knew there was going to be one), you need to be careful about which side you tilt it on.
Bad things can happen when you tilt it the wrong way. The key here is to locate the side of your mower that is home to your air filter and carburetor. Whether it’s on the right or left side will vary from mower to mower, so I can’t tell you exactly where you’ll find them. But they’re normally very obvious and you’ll see them right away.
When you tilt your mower up, this side (the one with the air filter and carb) needs to be facing upward. That’s very, very important. If the carb is facing downward, oil will make its way out of the breather tube that connects the crankcase and the air box, and you’ll end up with oil everywhere.
Why Some People Will Tell You this is a Bad Idea
Some folks will say that if you tip the mower on its side (whichever side), it’ll leak oil everywhere and could hydrolock your mower. It’s a bad idea they say. Which I think is why so many people get so hung up on this subject.
But if someone tells you this, they’ve missed a step. And it’s a step that will completely remove the chance of your mower becoming hydrolocked (hasn’t failed me yet!).
Before I explain what that step is, I think it’s important that you have some idea of what hydrolocking actually is. So here’s a very quick crash course. I’m not a small engine expert, but someone who is once explained it to me this way.
In your engine, the piston moves up and down in the cylinder. If the piston is in the down position when you tip your mower on its side, there’s a lot of space above it and it’s possible for oil to flow past the piston and the piston rings and basically flood the whole top portion of your piston with engine oil.
And then when you try to turn the engine over, the piston tries to squeeze that oil out, but it can’t and becomes locked. That’s hydrolocking in a nutshell.
Prevent Hydrolocking: How to Make Sure Your Piston is at Top Dead Center
The way you can prevent hydrolocking is to ensure your piston is at the top of the cylinder when you tip your mower over. There will still be a tiny gap between the top of the cylinder and the piston, but the oil won’t be able to completely flood the top of the piston now. At worst a little oil could be left on the top of it and on the spark plug. But hydrolocking is not something you’ll need to worry about.
To do this there are a few simple steps:
- With your mower in a normal position, flat on the ground, you’re going to pull on the starter cord, as if you were trying to start your mower. Remember to remove the spark plug lead first though, as you don’t want to actually start your mower.
- If you have a brake handle, pull it down.
- Now, pull softly and slowly on the cord. At some point as you pull, you’ll find a point where it feels tight. Repeat this process a few times so you get a feel for where that tight point is.
- When you’ve found that point, on the next pull only pull as far as that point. As soon as you feel it gets tight, let the cord go.
The piston is now at the top of the cylinder and you aren’t going to hydrolock your mower when you tilt it.
Additional Bonus: Your Valves Are Now Closed
Doing this before you tilt your mower on its side has another additional benefit. It closes the valves!
When you were pulling on the cord and it got tight, it feels that way because the valves are closed and it creates extra pressure.
And the only way the oil can move out of the crankcase and leak all over the place, is through an open valve. Problem solved!
That’s How to Tilt a Lawn Mower and Not End Up with a Mess
If you follow the steps outlined above, and then tilt your lawn mower the air filter side up, you won’t have any oil or gas leak anywhere. Seriously, mower air filters soaked in oil are not fun to deal with! Doing it this way, you can have it tipped over for as long as you need to finish whatever maintenance you’re doing. I have mine flipped over for a couple of hours sometimes, when I’m really giving my mower the full works – thorough undercarriage clean, blade sharpening or change, coating it in Fluid Film to prevent clippings from sticking – and I don’t have a drop of oil or gas on my workbench afterward.