Fixing 14 Common Issues with Simplicity Lawnmowers

You keep your Simplicity mower in good working order by using clean gasoline, regularly replacing the engine oil and hydraulic oil, and changing the filters.

Despite your best efforts, your lawn tractor, riding mower, or zero-turn will eventually break down owing to the inevitable effects of normal use.

I have compiled tables with the root causes and recommended remedies for a wide variety of ailments. In case you run into further issues, you can follow the provided links to additional in-depth publications.

simplicity mower

Before diagnosing, repairing, or operating, be sure you’ve read and understood all of the safety recommendations in the equipment’s operator’s manual. If you don’t feel confident in your ability to conduct the repair safely due to a lack of experience, training, or health, it’s best to call in an expert.

Issue 1: It Won’t Start on the Simplicity Mower

If your Simplicity mower won’t start, check for obstructions to the gas, air, and spark that the engine requires to start.

Also, check that you are using the correct procedure to turn on your mower. Before trying to start the mower, make sure the parking brake is engaged and the PTO switch is in the off position.

ReasonsCause of IssueOption
There’s no gas in the tankThere’s no more fuel in the tankPut in fresh gas
Bad or stale gasOver time, fuel deteriorates, reducing its effectiveness and increasing the risk of blocking the fuel system.Empty the tank and replace the fuel with fresh fuel. To prevent the fuel from deteriorating and to aid in the cleaning of the fuel system, use a fuel additive such as Sea Foam. Fuel up properly.
Gasoline cap is broken or pluggedA vacuum in your tank might hinder gasoline flow if the vent in the cap is clogged.To try and unclog the vent, use a fine wire. If the top has been knocked off, substitute it.
Faulty spark pluga spark plug that is either too dirty or damaged, has a poor connection, or is improperly gapped.Put in a new spark plug, tighten the connections, and check the gap according to the manual.
Air filter obstructionThe air filter might become clogged with dirt and grass, blocking airflow.To clean the filter, take it apart. If the filter is damaged, you should get a new one.
Stuck fuel filterReduced fuel flow due to a dirty fuel filter.Swap out the fuel filter.
Faulty gas pumpIf the fuel pump has failed or is leaking, there will be insufficient pressure to pump the fuel.Change out the gas pump
Clogged gasoline linesInadequate fuel delivery to the engine might result from the accumulation of sediment and dirt in the fuel lines.Clear the fuel line obstruction using carburetor cleaner and compressed air. If the line is broken, substitute it.
Unclean carburetorBad fuel and ethanol deposits can cause the carburetor to get dirty and clogged, cutting off the fuel supply.Carburetor parts should be cleaned thoroughly. If it needs to be fixed or replaced, do so.
Weak battery or dirty/loose terminalsProblems with starting might be caused by a dead battery, slack cables, or rusted terminals.Get your battery charged, and if it won’t hold a charge, get a new one. Remove any rust from the terminals and check that the cables are snug.
Defective safety switchTo avoid accidental ignition of your lawnmower, safety switches are installed. Your lawnmower might not kick on if a switch stops working.If the safety switch is broken, you should check it out and possibly replace it.
Ignition switch failureIf the ignition switch on your mower is broken, you will be unable to start it.A faulty switch should be checked out and perhaps replaced.
Cracked recoilIt’s possible that the rebound on your pull-start lawnmower is broken or damaged, rendering it useless.Inspect the recoil to see if it can be restrung, and replace any worn or broken components, such as the pulley. If the recoil mechanism fails, you should replace it.

Issue 2: It Died of Power Loss on the Simplicity Mower

Most of the same things that could keep your Simplicity from starting could also cause it to stop working mid-mowing.

If the engine dies soon after starting, check the choke setting. This is because the choke is engaged while the engine is cold and disengaged when it is warm.

If it isn’t set up properly, the engine will sputter and eventually stop working due to a lack of oxygen.

ReasonsCause of IssueOption
Poor fuelFuel degrades over time, resulting in less efficient gasoline that might block the fuel system and cause engine harm.Empty the tank and replace the fuel with fresh fuel. To keep the gasoline stable and the fuel system clean, you can use an additive like Sea Foam.
Air filter obstructionThe air filter might become clogged with dirt and grass, blocking airflow.To clean the filter, take it apart. If the filter is damaged, you should get a new one.
Unclean or damaged cooling finsThe engine block is not cooled properly because the cooling fins are clogged with debris.Clean the cooling fins and replace any that are broken.
Fuel line blockageThe engine may not get the fuel it needs if dirt and sediment build up in the fuel lines.To remove the obstruction from the gasoline line, you can use carb cleaning and compressed air.
Faulty Gasoline PumpWhen the carburetor is mounted in a location that is higher than the fuel tank, the fuel pump is employed to transfer gas to the carburetor.If your gasoline pump is malfunctioning, you need to substitute it.
Unclean carburetorBad fuel and ethanol deposits can cause the carburetor to get dirty and clogged, cutting off the fuel supply.The carburetor’s individual parts should be cleaned. Substitute if broken.
Damaged Gas CapWhen the gas cap isn’t vented properly, a vacuum accumulates inside the tank, preventing fuel from flowing freely.If your gas cap is leaking, you need to get a new one.
Low Oil Pressure in EngineWhen engine oil levels drop too low, excessive friction and heat are produced in the crankcase. The crankcase will pressurize if too much oil is used.Adjust the oil level in the engine. If the issue persists after trying this, you should call an engine mechanic for help. There may be damage to the engine.
Clogged Lawnmower DeckThe engine may fail if the deck is cluttered with grass clippings and other garbage.Maintain a clean mower deck by scraping it frequently. Wet grass is more likely to stick to the deck, so wait until it dries before cutting it.
Ignition Coil ProblemsWhen heated, the coil might come apart and cause a short, cutting off power to the spark plug.If there is a break in continuity in the ignition coil, it must be replaced.
Clogged Spark PlugAn intermittent spark could be the result of a dirty spark plug.When a spark plug becomes severely dusty or worn, it should be cleaned or replaced.

Issue 3: Lawn Mower Smokes on the Simplicity Mower

When your Simplicity starts puffing out smoke, either the engine is overheating, there is damage to the internal components, or oil is burning off a hot surface.

ReasonsCause of IssueOption
Blocked air filterWhen the air filter gets clogged with dirt and grass, the engine can’t breathe.Take apart the filter so it may be cleaned. If the filter is worn out, replace it.
Crankcase oil overfilledAn oversupply of oil can raise engine pressure and force oil into the cylinders via the valve mechanism.Get the oil level down to where it should be, as specified by the manufacturer.
Oil Level Too LowIf your engine doesn’t have enough oil, friction will increase and heat will build up.Take it in for an inspection at a small engine repair shop. Adding oil may help, but by that point it may be too late to save your engine.
Internal issuesUnresolved issues with the mower’s internal engine can have a negative impact on its performance.If you’re having issues with your Simplicity, take it to a shop that specializes in small engines.

Issue 4: Inadequate Hydrostatic Transmission on the Simplicity Mower

Hydrostatic transmissions are standard on zero-turns and lawn tractors from Simplicity. When the hydraulic is old or underpowered, the transmission may be sluggish.

Weakness can also occur if the drive belt or tensioner pulley is damaged.

ReasonsCause of IssueOption
Broken drive beltIf your pump’s drive belt is worn, it won’t be able to pull its weight.Belts that are worn out or frayed should be replaced.
Ineffective tensioner pulleyWhen a tensioner pulley breaks, the drive belt loses its tension.Switch out the belt and lube the tension arm.
Inadequate or stale hydraulic oilIf your hydraulic oil is low or old, it won’t lubricate the system properly, and your hydraulics will feel feeble.Hydraulic oil should be changed at the intervals suggested by Simplicity.
Make sure your hydraulic fluid is always full by doing regular oil checks.

Issue 5: Lawnmower Won’t Go Straight Or Steer Properly on the Simplicity Mower

Incorrect tire pressures, faulty dampers, and worn steering components are just a few of the things that might negatively impact your Simplicity mower’s maneuverability. A zero-turn mower may pull to the right or left if the tracking is incorrect.

ReasonsCause of IssueOption
Incorrect tire pressureMowers with uneven tire pressure can pull to one side.Maintain the recommended tire pressure by checking it regularly. Your mower’s tires on both sides should be inflated to the same level.
Poor zero-turn dampersMowers with faulty dampers will lurch to one side when being propelled.Get a new damper and put it in
Zero turn requires tracking modificationMowers have a tendency to veer to one side if one tire is going quicker than the other.The tire’s rotation speed can be altered by adjusting the corresponding bolt. Please consult the user guide.
Riding mower’s faulty steering due to worn or loosened partsMowers can become difficult to control due to worn bushings, washers, and gears.The failing components of your steering system need to be inspected and replaced.

Issue 6: The Mower Won’t Start on the Simplicity Mower

A broken or missing drive belt, a worn tensioner pulley, or a missing idler spring can all prevent a Simplicity lawn mower from functioning.

Incorrect placement of the transmission bypass rod or drive release lever might prevent a hydrostatic riding mower or zero-turn mower from moving.

Air in the hydraulic system or transmission damage are two other possibilities.

ReasonsCause of IssueOption
The bypass rod or drive release lever is misalignedMowers with hydrostatic drives can be used freely on a zero-degree rotation by depressing a release lever. On a riding mower, you’ll find something called a bypass rod.On a zero-turn, the drive release lever needs to be in the “operating” position. A disengagement of the bypass rod is required.
Drive pump belt has worn outIf the drive belt comes off, the mower won’t go anywhere. Wearing the belt may also prevent any movement.Belts should be replaced when they show signs of wear. Verify the pulley belt is properly fastened.
Failure of the tensioner pulleyFailure of the tensioner pulley’s bearing is possible.Substitute the tensioner pulley
Broken spring in the idler armThe stress on the drive belt will release if the idler arm spring breaks or disappears.The missing or broken spring must be replaced.
Inadequate or stale hydraulic oilIf your hydraulic oil is low or old, it won’t lubricate the system properly, and your hydraulics will feel feeble.Hydraulic oil should be changed at the intervals suggested by Simplicity.

Make sure your hydraulic fluid is always full by doing regular oil checks.

Warm hydraulic oilDamage to your hydrostatic transmission system can be indicated by hydraulic fluid that is abnormally hot.Cool the hydraulic oil down first. Mowers that perform well while cold but lose power when the hydraulic system heats up should be examined at a local Simplicity dealer.
Air in hydraulicsMower performance will suffer if air is not drained from the hydraulic system after changing hydraulic fluid.Take the necessary steps to purge the system of air.

Issue 7: Vibrations from the Mower on the Simplicity Mower

Loose hardware, worn or imbalanced blades, or debris stuck in the mower can all contribute to a Simplicity’s vibration problem.

ReasonsCause of IssueOption
Missing or loosened engine mounting boltsMower vibration can be dampened by using engine nuts while the engine is operating.Fasten the engine down and re-bolt if necessary.
Inadequate clutchVibration can result from a falling out of the clutch due to a failed bearing. The bushing and linkages of a manual clutch can break.Substitute a new clutch
Unbalanced or broken mower bladesBefore attaching them to the mower, blades need to be adjusted. Uneven or broken blades might also produce vibration.Repair or replace any unbalanced or broken blades.
The blade shaft was covered in foreign substance.Vibrations can be caused by foreign objects tangling with your blade shaft, such as string or long weeds.Clear the area around the blade shaft of any obstructions. Inspect for broken spindles.
Damaged bearings in the spindle housingCheck if the spindle housing bearings are faulty, since they could be the source of the vibration.Either the bearing or the entire spindle housing must be replaced.
Broken pulleys or deck beltBelt and pulley wear and bearing failure should be checked on the deck.Put in new belts and pulleys if they are old or broken.
Mower clogged with debrisSmall objects like stones, acorns, woodchips, and other debris might become caught in the mower’s pulleys or other moving parts. Your mower may vibrate sometimes as a result.Mower deck and machine must be inspected for crevices that could trap small objects. Take out the invaders!

Issue 8: Heat Stops Mower on the Simplicity Mower

When it becomes hot, there are a number of things that can cause a Simplicity mower to stop working. It’s common for this to happen when there are problems with the fuel, the oil, the amount of oil, the cooling fins, the ignition coil, or the mower deck.

ReasonsCause of IssueOption
Clogged air filterDirt and grass can plug the air filter preventing airflowRemove the filter and clean it. Replace the filter if it is in bad condition.
Bad or Old FuelAs gas degrades, it leaves behind varnish and other sticky deposits.Get rid of stale gas. Add a fuel system cleanser and stabilizer, such as Sea Foam or STA-BIL, to your new gas tank before filling it up.
Dirty carburetorThe residue left by old fuel might accumulate, clogging the fuel jet and rendering internal parts useless.Take out the carburetor so you may clean it with the proper fluid. If it needs to be fixed or replaced, do so.
Incorrect Motor OilThe engine’s temperature can rise if the incorrect oil type or viscosity is used.Kawasaki recommends using air-cooled engine oil in its motorcycles.
Over-Oiling the EngineWhen there is too much oil in the engine, the pressure might force its way through the valves and into the cylinder.Take some oil out of the engine until you reach the level specified by the manufacturer.
The Engine Has Too Little OilIf your engine doesn’t have enough oil, friction will increase and heat will build up.Take it to a shop that specializes in small engines or a Simplicity dealer so the damage may be assessed. It may be too late to fix your engine by the time you try to add oil.
Blockage of Cooling Fins in EngineBlocking airflow is dirt and debris that has accumulated in the cooling fins. The engine block is kept cool by a flow of air pushed by the cooling fins.Remove dust from the cooling fins and repair any that are damaged. Get under the hood and scrub the engine block.
Ignition CoilWhen the coil becomes too hot, the windings can come loose and it won’t work.The ignition coil can be checked with an ohmmeter. When you see a discontinuity, make the necessary corrections.
Blocked Deck on LawnmowerWhen grass clippings accumulate on a deck, it becomes difficult for the blades to rotate under the surface. When the deck is clogged, the engine has to work harder.Maintain a clean mower deck by scraping it on a regular basis. Don’t mow the grass when it’s damp to prevent accumulation.
Engine gasket, piston ring, or valve train issuesUnresolved issues with the mower’s internal engine can have a negative impact on its performance.If you’re having issues with your Simplicity, take it to a shop that specializes in small engines.

Issue 9: Mower is Having Rough or Stuttering Performance

Air, gasoline, or spark deficiencies might cause a Simplicity lawn mower to stall.

Overworking the engine with a fast ground speed, low engine speed, plugged mower deck, or dull lawn mower blades can cause this.

ReasonsCause of IssueOption
Air filter cloggedDirt and grass can clog air filters.Clean the filter. Replace damaged filters.
Choke Got Stuck or Was Set WronglyToo much or too little air can cause the mower to sputter if the choke isn’t properly adjusted.Once the engine has warmed up, the choke should be opened. Verify the choke plate, choke cable, and choke lever are all in the correct positions.
Old gasThe breakdown of fuel leaves behind varnish, which can limit fuel flow and eventually lead to component failure.Fuel system cleaning and fuel stabilization can be achieved by draining the fuel tank and refilling it with new gasoline stabilized using a fuel additive such as Sea Foam.
Stuck Fuel LineIf a fuel line becomes clogged, the flow of fuel is reduced.Use carburetor cleaner and compressed air to clear the fuel line of the obstruction. If there are cracks in the line, it’s time to get a new one.
Fuel Filter PlugFuel flow can be restricted if dirt clogs the fuel filter.A clogged fuel filter should be changed.
Dirty carburetorOld fuel’s varnish can build up and make moving parts sticky.Take the carburetor apart and clean it. If it’s broken, fix it or get a new one.
Broken Gas CapIf the gasoline tank cannot vent because the gas cap is not open, a vacuum will create inside the tank and not enough gas will reach the carburetor.Put on a new fuel cap.
Spark Plug ClogThe spark may be erratic if the spark plug is filthy.Spark plug should be changed. Check the space and make sure the spark plug wire is secured tightly.
High Speed on the GroundMowing thick, tall, or wet grass at a high ground speed might put a strain on your Simplicity’s engine.Mow at a pace appropriate to the ground and weather circumstances.
Slow MotoringMower blade engagement is a power-hungry operation. The mower will sputter and stall if the engine rpm is too low.Raise the accelerator pedal to its highest setting.
Deck CloggedGrass clippings and other debris on the deck make the engine work harder to turn the blades.Clean off the mower’s deck.
Dull Lawnmower BladesThe engine is already working harder than necessary to turn dull blades through a clogged mower deck.Take off the mower blades and get them sharpened. Reinstall them after balancing them.

Issue 10: No Cutting Action from Lawnmower

When the clutch won’t engage the mower blades, it’s time to check for potential causes.

Choke cable and linkages for manually engaged clutches, or battery and PTO switch for electric clutch types.

ReasonsCause of IssueOption
Used Harness BeltThe blades can’t be turned by a worn belt since it can’t hold the pulleys.Belts that are broken, shiny, or otherwise damaged should be replaced.
Belt Slipping Off the GearsBelt tension could be lost due to a worn idler arm and spring. It’s possible that the belt is too big and loose. The belt could slip if the pulleys are not perpendicular to the deck.Renew any decking that looks old or damaged. Stretched deck belts should be replaced immediately. Make sure the belt goes around the pulleys in the right way.
PTO Switch FailureThe blades won’t spin if the battery can’t activate the clutch because the PTO switch isn’t on.Fix a malfunctioning PTO switch.
Awful GripWhen the clutch is worn or broken, power cannot be transmitted from the engine to the blades.A worn-out clutch should be changed out.
The Clutch Cable, Lever, Spring, and Linkages Have Worn OutWhen the clutch cable, lever, spring, or links on a manual engagement clutch are worn, the clutch may not engage.Fix broken stuff.
Draining BatteryA feeble battery can’t drive the clutch.If the battery tester shows that your 12-volt battery has less than 12.7 volts, you should charge it.
Faulted safety switchThe blades won’t spin if the seat switch doesn’t detect the operator.Get rid of a dead battery.
Fuse BlownA blown fuse serves as a safety mechanism for electrical equipment. There won’t be enough battery juice for the mower parts.Use another fuse of the same amperage to replace a blown one. If the mower keeps blowing fuses, have it checked out by a mechanic to determine why.

Issue 11: Gas Mower Leaks

Finding a leak in a Simplicity mower can be challenging, especially if you don’t notice it in time for the gas residue to evaporate.

The best course of action is to trace the fuel line from the tank to each component along its route. If you’re still having trouble, a faulty gas cap seal could be the source of the problem.

ReasonsCause of IssueOption
Faulty Gasket in the Carburetor BowlWhen the gasket dries up, the seal breaks and gas begins to leak.Change the gasket in the bowl of the carburetor.
Needle Float for a Blocked CarburetorIf the gas is old, the float or float needle may become stuck, resulting in gasoline spillage.Scrub the carburetor and swap out any worn components.
Broken Gasoline PipesCracks can form in aging fuel lines.Fix the leaky fuel line.
Damaged Gas TankPoly tanks have a tendency to deteriorate and spring leaks at the seams.The gas tank must be changed. Repair the tank if a replacement is not immediately available.
Failure of the Fuel Cutoff ValveA leaking shutoff valve is a major problem.Switch out the stopper.
Defective Fuel FilterThe plastic fuel filter housing or fuel filter itself is susceptible to degradation from the fuel.Get a new fuel filter.
Gasoline Pump Is BrokenDegradation and seam weakness in the gasoline pump are possible.Change out the gas pump.
Cracked Seal on Gas CapThe gas cap’s seal might dry out and become ineffective over time.Change the gas cap.
Broken Priming BulbIt’s possible for the priming bulb to break or for the line behind it to become slack.Get a new priming bulb and install it.

Issue 12: Mower Makes a Clicking Sound and Won’t Start

The Simplicity engine might make a clicking or humming sound, and it might not turn over. This may occur if the starter on the mower is not receiving power.

While a faulty starter solenoid is likely to blame, you should also examine any components that restrict power from reaching the solenoid.

ReasonsCause of IssueOption
Battery Cables and Wiring DamagedPoor conductivity can be caused by wiring, cables, or terminals that are loose or damaged.Take care of corrosion and replace any broken parts. Check the connections of all wires and cables.
Poor or Weak BatteryThe engine won’t turn over or start with a poor battery.If the battery is dead, you should put it on a trickle charger. Discard a dead battery and get a new one.
Poor GroundStrong, corrosion-free connections are essential between the battery and the starter solenoid’s ground terminals. Self-grounded (a 3-post solenoid).Make that it is securely grounded to the mower and that any corrosion has been removed.
Defective Starter SolenoidIf the starter solenoid fails, the starter motor won’t turn over.If the starter solenoid fails the test, it must be replaced.
Starter Motor ProblemsIf the starter motor is faulty, the vehicle won’t start.Fix it by getting a new beginning.

Issue 13: Mower Produces an Uneven or Poor Cut

Several factors can make a Simplicity deliver an unsatisfactory shave. Tire pressures must be checked first, followed by the mower deck’s individual parts.

The lawnmower might be performing as expected. You merely need to adjust your speed to the current weather and road conditions.

Damaged or dull lawnmower bladeTire pressure variationsThe throttle is set too low
Warped mower bladeUneven surface on mower’s deck.Too rapid ground speed
Incorrectly fitted bladeThe blade’s bent spindle.Damage to the deck
Dirt clogs deckBelt or pulley problems on the mower deckMechanical failure

Issue 14: Overheated Engine

If you notice a hot engine odor, you should turn off the engine immediately to save costly repairs.

Start investigating potential causes of engine overheating, such as insufficient oil, improper oil, or debris blocking airflow to the radiator.

ReasonsCause of IssueOption
Incorrect motor oilIf you’re using an air-cooled engine with the wrong oil for the temperature outside, your engine could overheat.Remove the old oil and replace it with new, air-cooled oil of the appropriate viscosity for use in the open air.
Oil Level Too LowIncreased friction and heat result from a lack of lubrication.It’s time to get some new oil and change the old. A small engine mechanic should inspect the engine for damage caused by low oil.
Blocking engine cooling finsIf the cooling fins on your engine are blocked or broken, the airflow that keeps your cylinder heads and block cool will be compromised.Remove debris from cooling fins. Fix the broken fins.
Lacking or improperly installed engine guardThe engine guard protects the engine while allowing air to flow freely around it.Fasten the engine guard tightly.
Air filter obstructionThe engine will have to work harder to locate air if the air filter is excessively dusty.Take care of the clogged air filter.
Debris on mower deckThe engine has to work harder to turn the blades through the trash on the deck.Remove debris from the mower deck by scraping it.
Faulty mower bladesA blocked deck is made much worse by dull mower blades.The mower blades need to be sharpened and balanced.
Motor overworkedWhen attempting to cut more grass than the mower can handle at once, long, wet, or thick grass might overwork the engine.Adjust your speed to the lawn-mowing environment. Do not attempt to trim wet grass. Cut the grass twice or three times if it has gotten too long.