The Best Guide To Levelling Your Lawn Mower Deck

If you have been noticing an uneven cut to your lawn recently and your mower blades are still new and sharp, then you might have an uneven mower deck which is causing the problem. 

Using your lawnmower with an unlevel mower deck means the right-hand blade tip will end up being either lower or higher than the left-hand blade tip, resulting in an uneven cut on your grass or even potential ruts in your lawn.

Luckily, a lawn mower deck level adjustment can solve this issue and be achieved with a simple socket and wrench so your mower can be working at the correct even deck height.

To explain how to do this further, we have put together a short step by step guide below that will take you through how to adjust an unlevel deck. 

Step By Step Guide To Leveling a Lawnmower Deck

Levelling your lawn mower deck is straightforward and easy to do, even as a beginner you can follow your manual instructions to do this, and proper deck adjustment can solve many issues such as dead grass patches, blunt blades and an uneven cut. 

We have broken down how to level your mower deck on a riding mower into simple steps for you to follow below. 

• Step One - Park your riding mower on to a level surface and put the parking brake on to stabilise it while you investigate the mowing deck. Put the level in a disengaged position too, turn it off and remove the key completely from the ignition key slot. 
• Step Two - Disconnect the spark plug wire for further safety reasons then check the tyre pressure with a gauge to make sure each tyre is at its maximum PSI, this will make sure you have a proper deck adjustment that is accurate.
• Step Three - Rotate the blades to the sides of the lawnmower and measure from the edge of each blade side to the level ground, take both measurements then subtract one from the other to get the difference. More than a 1/8 " will mean you need to make a manual adjustment. 
• Step Four - Turn the adjustment nuts or link lock nut on each rear wheel to make a proper deck adjustment, most lift link lock nuts will operate by turning clockwise to raise and anti to lower. 
• Step Five - Now swap the front and rear blade around and use the blade tip measurements closest to you to measure. If the front blade to rear blade angle is over half an inch lower then the rear blade tips will need to be adjusted. 
• Step Six - Loosen the jam nut with your wrench and adjust the manual deck lift lever nut until the rear and front blade angles are at an acceptable height. 
• Step Seven - Secure everything back on to your mower and ensure everything is tightened on your machine how it should be, replace the spark plug and test out the mower to ensure everything is working properly. 

Frequently Asked Questions About Leveling a Mower Deck 

Why does my right-hand blade tip keep going lower than my left-hand blade tip? 

This uneven cutting deck might be caused by loose adjustment nuts which are getting knocked and moved when you use your mower on bumps or rough terrain around your garden.

Check the mower's manual for specifics on how to adjust your deck properly. 

What is the best cutting height deck height for tall grass? 

For very tall grass, your mowing deck height should be anywhere between 3-4 inches high to tackle the tough grass with ease and cut evenly.

How do you adjust a push mower cutting deck height? 

You can adjust the mowing deck height of your push mower by following the instructions above, except you will have to raise your mower level to gain access to the cutting deck. 

Last Words 

Overall, adjusting the mowing deck height should be done whenever you notice an uneven cut coming from your mower, just simply follow the step by step guide above to measure your blades accurately and make adjustments where needed by changing the knobs. 

Always follow safety instructions from your mower while working around the deck area and remove the spark plug at all times.