Reasons Why Your Riding Mower’s Blades Won’t Start or Engage

When you turn on the PTO, nothing occurs. Even if it does start up, the mower blades won’t move.

A worn deck belt, worn tensioner spring, defective pulley, faulty PTO switch, faulty clutch, weak battery, broken safety switch, blown fuse, or worn clutch cable can prevent the riding mower blades from engaging or turning on.

If you need to make repairs on your mower, make sure you first read and follow the safety instructions in the owner’s handbook. The ignition key and spark plug wires must be disconnected. It’s best to wait until the engine has cooled down and everything has stopped moving.

Riding Mower Blades
Riding Mower Blades

Before diagnosing, repairing, or operating, be sure you’ve read and understood all of the safety recommendations in the equipment’s operator’s handbook. If you are unsure of how to proceed, if you lack the necessary knowledge, or if your health prevents you from completing the repair safely, you should seek the advice of a professional.

Riding Mower Blades Won’t Engage or Turn On

Deck Belt of a Riding Mower in Use

To turn the mower blades, the deck belt is meant to fit snugly around the pulleys. Blades that have seen too much use may lose their bite on the pulleys.

Check for fraying in the deck belt. Indicators of this condition include a belt that has been stretched, fractures forming in the belt, or fraying at the edges. A belt that has seen better days may also seem glazed and sit low in the pulley grooves.

Belts on riding mower decks can wear out and need to be replaced when they exhibit indicators of needing to be replaced. A worn belt that slips on the pulleys may reduce blade speed, even if you don’t identify the belt to be the cause of the problem.

A poor cut may arise from a sluggish blade speed.

Riding Lawn Mower Tensioner Spring

A tensioner spring is used to keep the idler pulleys in place. Either the spring or the hole in the bracket or deck through which it passes might become worn over time.

This might lead to the belt becoming loose and vibrating off the pulleys.

If the tensioner spring is broken or missing, it has to be replaced. If the hole in a bracket is getting bigger over time, you should replace the bracket.

The Pulley on Your Riding Lawnmower Has a Worn Bearing

A damaged bearing in a deck pulley might result in the deck belt slipping off the pulleys and rendering the blades inoperable.

When the pulley’s bearing fails, it will no longer be able to stay level and fastened to the deck. In extreme cases, the pulley may start to shake, causing the belt to slip off.

Please check the deck pulleys. Slowly rotate each pulley by hand to make sure they can rotate freely. You should check for a bearing noise and the pulley should jiggle. When any of these occur, it’s time to replace the pulley since the bear is worn.

Your Belt Keeps Falling Off Your Riding Mower will provide other explanations for why your deck belt keeps coming unfastened or breaking.

Riding Lawnmower with a Bad PTO Switch

Most lawnmowers include a knob on the handlebars that may be turned to activate the PTO switch and hence the clutch, which permits battery electricity to be used. A broken switch means no fan will spin.

Examine the switch for a lack of continuity. Change the function of a switch with a pause in action.

Ineffective Clutch on a Ride-On Mower

Power is transferred from the engine to the blades through the drive belt via the PTO (Power Take Off) clutch. If a worn or broken clutch is the cause of the blades not turning, it has to be replaced.

A Study of Lawnmower Clutches will provide you the information you need about these mechanisms.

Manual Clutch Riding Mower with a Worn Clutch Cable

If your riding mower has a clutch that has to be engaged manually, you’ll locate a clutch lever and cable. It is possible for the lever, cable, and linkages to get worn to the point where they are no longer effective.

Be sure the clutch is being engaged by inspecting the clutch lever, cable, spring, bushings, and linkages. Fix any broken or worn items immediately.

Weak Riding Lawn Mower Battery

For an electric clutch, the battery is the source of power. Lack of electricity from a low battery prevents the riding mower’s blades from spinning.

Use a multimeter to measure the battery’s voltage. The voltage of a fully charged 12-volt battery should be around 12.7 volts.

When the battery level drops below this, it has to be charged. There are likely a number of factors contributing to the premature demise of your battery, many of which are discussed in 5 Things That Are Draining the Life of Your Lawn Mower Battery.

Charge a Riding Mower Battery: Charge a battery using a battery charger. Put on safety glasses and gloves to guard against electrical shock before proceeding.

If you have a riding mower that needs charging, here are the steps you should take:

  • Obtain entry to the connections and batteries. A screwdriver may be required to access the battery. The battery is either underneath the seat or in the engine compartment. Keep the battery within its case at all times.
  • It is recommended that the positive cable be connected first while charging a battery. We’re talking about the plus-sign cable, which is either red. Hook up the wire to the battery’s positive terminal.
  • Join the negative end of the cable to the battery’s negative post. The negative-sign cable, often known as the black cable.
  • Do not risk electrocution by touching anything that has not been rubber-coated.
  • Adjust the charger’s voltage and current to suit your needs. Lawnmower batteries typically have a voltage level of 12 volts. The battery may be charged more quickly with an increase in amperage. It’s recommended to begin with 2 amps and gradually increase up to 10 amps. It’s best to charge slowly.

A new battery should be used if you notice the old one doesn’t retain a charge. Batteries for 12-volt lawn mowers are available at most home improvement and auto parts stores. Batteries can also be purchased at a store that sells lawnmowers.

Don’t forget to bring the dead batteries. If you don’t return your old battery, most shops will charge you a core fee. The typical basic charge is $20.

A Riding Lawnmower with a Defective Safety Switch

Safety switches play an important role in the operator presence system, which aims to ensure the user’s wellbeing. When you sit in the seat, a safety switch under the seat will tell the safety system that someone is there.

With no one in the driver’s seat, the safety system will not enable the blades to spin. The mower blades won’t spin if the seat switch breaks.

If you suspect a faulty seat switch, you may either test it with a multimeter or temporarily disable the safety switch. Do not start mowing without first installing the safety switch.

Safety switches should be present and operational on all machinery at all times.

Riding Lawnmower Blown Fuse

A blown fuse might be to blame when you find that the clutch is not receiving electricity from the battery. A fuse is installed to safeguard the mower’s electrical components.

A short, faulty wiring, or defective component are all potential causes of a blown fuse.

Put in a new fuse with the same amperage rating as the old one. If you keep having electrical problems with your mower, I suggest taking it to a lawn mower repair shop or your local mower dealership.

Is Your Ride-On Mower Still Giving You Trouble?

When you’ve had a lawn mower for a while, it’s certain to develop some sort of issue. This might include issues such as smoke, uneven cutting, loss of power, refusal to start, fuel leakage, and more with your riding mower.

Have your riding mower looked at by a professional if you are unable to fix it yourself or if you do not feel comfortable attempting a more involved repair.

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