You are trying with all your might, but the mower deck is stuck in place and won’t move. It doesn’t matter if the deck is in the up or down position or somewhere in between; it just won’t budge. But, with some troubleshooting and persuasion, you’ll have the deck free and be back to cutting in no time. I’ve put together some of the techniques I’ve had to use over the years and created my step-by-step guide to freeing your stuck mower deck. Let’s have a look.
Reasons Why Your Deck Could Be Stuck (The Short Answer)
There are a number of reasons why your mower deck could be stuck. The most common are the release pedal being rusted or it being jammed into the frame after a collision.
Why Your Mower Deck is Stuck (5 Possibilities)
If you have left your lawn mower for an extended period, it may have fallen victim to rust, and now the mower deck is stuck. Or you may have hit something hard, and it’s jammed. But first, I’ll assume you have removed the deck safety pins that stop the deck adjustment. The issue is likely one of the following:
Deck Jammed Up on the Inside
If you hit a stump or some other object while cutting, you may find that the deck has become stuck in position. If this happens, it’s best to stop on level ground and take a look. First, switch off the lawn mower and apply the brake. If you can, ensure the deck lift lever is secure so the deck can’t suddenly drop.
Look under the mower and above the deck to see if anything seems out of place or bent. If all is looking normal, then it’s probably just jammed.
Lift Pedal Rusted Tight
You are more likely to come across a rusty deck lift pedal at the start of the season after the mower has been sitting for some time. First, try lifting the footplate if your mower has one or peer between the mower body and deck. You should be able to see the mechanism.
Next, apply pressure to the pedal as if trying to adjust the deck and see what happens. You will want to get some assistance if you can’t do both simultaneously. If the pedal is stuck to the adjoining bracket or lifting section, it’s probably rusted together.
Bent Lift Pedal or Lift Lever
It’s surprisingly easy to bend a lift pedal and lever. It can happen while the lawn mower is in use or if something heavy is placed on it during storage. Have a look at both and see if they appear to be damaged. If you discover that either is bent, it could be why the deck isn’t moving, and you’ll need to straighten it out.
Lift Lever Rusted
The lift lever is susceptible to corrosion, just like the deck pedal. Depending on your lawn mower, you may have a release button on the lever itself. Check both the lever and button to see how they function.
Then, following the same approach as the deck pedal, look for connections that should be moving. You have found the problem if these are stuck or not working correctly.
Lifting Pistons Seized
Many mowers with heavy decks have pistons to assist in lifting the deck’s weight. These pistons commonly work under their own pressure and are not hydraulic pump-driven. Locate your pistons and check for movement.
To do this, you may need to remove the piston to check what it does. You’ll have diagnosed your issue if it fails to do anything.
How to Fix a Stuck Mower Deck (Step By Step)
Now that you have diagnosed the cause of your stuck mower deck, you can use my step-by-step guide on fixing the individual problems. I’ll also explain what tools you’ll require.
Releasing a Jammed Deck
This fix requires very few tools other than your weight. First, apply weight with one foot to the deck and see if it drops. Repeat this a few times, going from one side of the deck to the other.
The repeated downwards force could be enough to drop the deck. I’m not telling you to jump on it, but you can be a little forceful. If this fails and you’re sure where the jam is located, use a pry tool and separate the pinch. Just watch out as the deck will more than likely drop an inch or two.
Tools Required to Release a Jammed Deck:
- Pry Tool.
Releasing a Lift Pedal That’s Rusted Tight
First, ensure that the deck is locked so it cannot fall. Then, locate the rusted joint and spray a rust penetrant. Allow the spray to work its way into the joint for 5 to 10 minutes, and try adjusting the deck.
If this fails, then respray the affected area with the same penetrant. Finally, give the pedal another try and see if it’s worked. This should be enough to free the joint, but if this method fails, then you can try to pry the joint apart.
Take a screwdriver and hammer and lightly tap between the joints using the rust penetrant as needed. With a few taps, the joint should release.
Straightening Out a Bent Lift Pedal or Height Lever
I find it best to use an adjustable wrench to clamp the metalwork instead of a hammer to avoid causing any additional damage. Simply place the wrench where you can get a good grip and apply pressure until you get it straight. I find the longer the wrench’s handle, the easier the fix.
Tools Required to Straighten Out a Bent Lift Pedal or Lift Lever:
- Adjustable Wrench.
Lift Lever with a Bad Button
If the lever has a bad button, you’ll probably find the spring has gone, or the lever mechanism is rusted. If the spring is still in place, take a rust penetrant, spray the whole area, and leave it to sit for 5 to 10 minutes. Then, try to work the button free. If you’re struggling, take a screwdriver to pry it loose.
You’ll need to operate the mechanism manually if the spring is missing. A missing spring will cause the button to stay in the ON position. Some buttons can remain in this position and operate, but it’s usually a safety feature to lock the lever and needs to be reset each time by releasing the button.
First, take a set of pliers, grip the button, and pull it out. Doing this should reset the lever. Finally, you’ll need to replace the spring. Simply attach the new spring to the button and the lever.
Tools Required to Release a Bad Button:
- Rust Penetrant.
- Screwdriver Pry Tool.
Lifting Pistons Seized
Pistons can quickly seize when left with either rust or caked-on dirt for an extended period. It‘s uncommon for them to seize internally; it’s usually just externally.
Locate the piston and free one end from the deck. They are usually locked in place with a bolt or pin. Use either a socket for a bolt or pliers for a pin, and release one end of the piston.
A good piston will extend or contract when released from its mount. If it doesn’t do this, then you know you’ve got a bad piston. With the piston removed, you should be able to move the deck. Just be careful, as it will be much heavier without the piston.
Place the piston in a vice, and give the moving parts a good clean. Spray a lubricant where the pin goes into the piston. Alternatively, use a rust penetrant if you find rust. If you get the piston to operate under its own effort, you can reinstall it back on the mower. If it’s stubborn, then it’s best to replace it.
Tools Required to Remove and Fix a Seized Lift Piston:
- Socket Set.
- Cleaning Rag.
- Spray Lubricant.
- Rust Penetrant.
Tips for Not Getting a Stuck Mower Deck in the First Place
- Store the lawn mower where it’s not going to get damaged.
- Avoid running over obstacles.
- Regularly clean the lawn mower.
- Spray lubricant on all moving parts between uses.
- Avoid using the lawn mower in wet conditions to prevent rust.