The 44-inch mower deck of a Cub Cadet lawn tractor contains three cutting blades that are 15.94 inches long. The blades are secured to spindles that protrude through to the underside of the deck. Pulleys atop the spindles are driven by a belt that gets its power from an electric clutch that is mounted to the mower engine.
The blade is held securely to a spindle on the underside of the cutting deck with a threaded nut. The nut takes a 1 1/8 inch wrench or a 1 1/8 inch socket attached to a ratchet wrench. It is not recommended to use an adjustable wrench, as the corners of the nut can be rounded off if the wrench slips, making it difficult to remove or replace the nut.
If you lose one of the blade retaining nuts, use a replacement that has a ¾ inch inside diameter, a count of 16 threads per inch and a grade of 8. Using a nut of the wrong size or grade could cause the blades to come loose from the spindles while the mower is in use.
To keep the blade from rotating while you are trying to loosen the retaining nut, wedge a block of wood between the end of the blade and the closest deck baffle. Once the nut is loosened with the wrench or socket and ratchet wrench, finish removing the nut by hand while holding the bottom of the blade up. Once the nut is removed, the blade can be lowered from the spindle and removed.
Be careful not to lose the spacer, which is mounted in between the blade and the spindle. Replacement blades are installed in the reverse order. Ensure the side of the blade that is marked “bottom” or “grass” is facing downward, or the blade will not clip the grass correctly. Place a torque wrench on the nut and tighten it to the torque indicated in your Cub Cadet owner’s manual.