Are Lawn Mower Blades Reverse Thread? (Solved!)

Both yes and no. Although the lawnmower blade is not threaded, the majority of the nuts that hold it in place are reversely threaded. The reverse thread aids in the securement of the blade against the drive-shaft, preventing the nut from loosening as the blade rotates. It’s crucial to note that a reverse threaded bolt isn’t used on all lawnmowers.

Lawnmowers assist in the maintenance of lawns and the cutting of grass. Lawnmowers, like all equipment, require routine care and maintenance.  To remove your blade for sharpening or replacement, unbolt its lock nut, which is often reverse-threaded, with a socket wrench.

What Direction Should I Turn to Change the Mower Blade?

When you mow with a walk-behind mower, the blades spin clockwise, or right. The blade’s secured bolt must be turned counterclockwise or left, to be removed. Tip the lawnmower on the side including the air cleaner turned up and obstruct the blades with a bit of timber to make sure it can’t just turn before undoing the blade.

Checking the Fit of the Lawnmower Blade

Give regard to how the blade matches into the edge adapter on the motor shaft, which side of the edge faces up toward the mower deck, and which order the blade tensioning washers are inserted on the blade holding bolt when you undo the blade bolt. 

Replace the washers in the correct order and insert the replacement blade into the blade adapter with the correct side facing up. Tighten up the blade holding bolt to a torque of 30 foot-pounds or the energy amount provided in your mower handbook by rotating it clockwise or right.

How does a Lawnmower Blade work?

The blades that cut the grass are arguably the most fascinating element of lawnmowers. They’re also the ones that grab our attention the most when we look at a working lawnmower.

So it’s understandable that the blades have piqued the interest of many, prompting many theories regarding the blades, their orientation, and their integration with the internal combustion engine, all of which have been crucial in determining the sort of lawn mower a particular mower is.

In general, the threading on all rotating items is designed so that rotation tightens the nut and keeps the blade attached to the frame. By rotating the blade center in the opposite direction of the blade’s regular cutting rotation. Tightening refers to a left-handed thread that is loosening in a clockwise manner. Loosening refers to a right-handed thread that is loosening in a clockwise direction.

What are Blade Nuts? 

To attach the blade to the engine’s driveshaft, most lawnmower blade nuts are reverse-threaded. This prevents the nut from loosening while the blade rotates. However, some blades aren’t secured to the engine’s driveshaft using a reverse-threaded nut.

The Safety Behind The Blade Threading

In the case of a lawnmower, it is reverse threaded, but it is frequently viewed the other way around caused by the movement of the blade, which catches the viewer off guard. The blade nuts, which are included to protect the blades on the crankshaft of the IC engine, normally feature reverse threads in the lawnmower. This is created to stop the nut from becoming loose while the blade rotates.

The Removal and Installation of Lawn Mower Blades

It’s critical to keep a blade level while removing it for maintenance, sharpening, or replacement. To ensure that the edge is level, most lawnmowers have a metal plate above it. The blade will not cut your grass if it is reinstalled inverted. 

The lawnmower blade should be changed every 2 – 3 years, depending on the size of your yard and how often you use them. Sharpen the edge with a handheld rotary tool with a grinding stone attachment.

Safety When Changing Lawn Mower Blades

Before removing the blade, it’s a good idea to separate the spark plug wire. Blade-lock gadgets are also available on some lawnmowers, which aid to keep the blade in place while removing and reinstalling it. By the blade locking not only prevents the blade from moving while you spin the lock nut, but it also prevents the engine from starting while you’re working on it.

How to get a Lawnmower Blade Unstuck

Over-tightening can cause a lawnmower blade to become stuck for a variety of reasons, one of which is over-tightening. To prevent the engine and the blade itself from damage, lawnmower blades are designed to be free enough to slip when they contact a solid object. 

If the bolt is threaded in the wrong direction, the lawnmower blades may potentially become stuck. Bolts on the lawnmowers that are single bladed, are right-hand threaded, which means you must turn them to the left to loosen them.

Right and left-handed threaded blades are seen on several twin-blade walk-behind mowers and lawn tractor mowers. Note the direction the blade cuts grass to determine which blade you have. Left-handed blades have a right-hand thread, while right-handed blades have a left-handed thread. 

Rounded bolts could also be to blame – this could happen if the bolt is old and corroded, or if the tool is old or broken, or if the improper size or tool is used to remove a stuck bolt.

How to Remove a Stuck Bolt

Make sure it’s safe to take off the bolt before you go ahead and do it. Disconnect the plug line and place it in a safe place. If your mower has a gas tap, make sure it’s turned off before continuing. To prevent gas from escaping, turn the mower on its side so the carburetor is facing up.

Examine the condition of the bolt. If the bolt is rusted, use a wire brush to remove as much rust as possible. Spray the bolt with WD40 making sure to cover the blade above and below the blade and give it time to absorb into the threads. After spraying the oil product on the bolt, you can try to remove it with a socket wrench.