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MTD Lawnmower Starting Problems: Troubleshooting with Fixes

Having an MTD-built lawnmower can ease your garden maintenance routine. However, a lawnmower demands regular upkeep, which can make the machine malfunction if not done after reasonable intervals. Typical problems may include the lawnmower not starting at all or losing power after starting.

MTD lawnmower starting problems:

Riding and self-propelled MTD lawnmowers will struggle to start if they run on inadequate or stale fuel, the carburetor is gummed up with fuel deposits, or the air and fuel filters are in poor condition. Sometimes, the spark plug may have damaged electrodes that can affect ignition. Other factors, such as a tripped circuit breaker or a faulty starter switch, may also prevent the lawn mower from starting up. (in the case of electric lawnmowers).

Let’s dig deeply into these problems and look at how MTD lawnmowers, both electric and gasoline, can be fixed.

Contents

Troubleshooting an MTD Lawnmower: Where to Begin From?

Gas-powered lawnmowers are highly likely to experience starting problems due to the added complexity resulting from the presence of the engine, the fuel, and the ignition system. If you encounter such problems, here’s a short checklist that needs to be a part of your troubleshooting procedure.

1. Check for Fuel-Related Problems

An empty fuel tank is one of the most obvious reasons why your MTD lawnmower isn’t starting. If the tank contains old fuel contaminated with moisture and dirt, that can clog your carburetor and fuel lines, preventing the mower from powering up.

Another reason is a clogged fuel filter. A clogged fuel filter starves the engine from adequate fuel, thus affecting the power output. Although, not all mowers have a fuel filter so this may not be an issue for every mower.

– What to Do?

  • Drain the stale fuel: Use an oil siphon to drain the stale fuel out.
  • Replenish the tank: Refill the tank with fresh fuel as the manufacturer recommends.
  • Use stabilizers: Add a fuel stabilizer to extend the fuel’s life.
  • Replace the fuel filter: Clean or replace the filter based on the clogging situation.

2. Clogged Air filter 

If your engine doesn’t start after adding fresh fuel and cleaning the fuel filter, the next step should be to check and clean the air filter that may be blocked with dirt.

The carburetor is responsible for mixing the fuel and air in a suitable ratio to start the engine. The air must first pass through an air filter before reaching the carburetor.

However, if the air filter is clogged with dirt and debris, the carburetor will be starved with air, which will upset the air/fuel ratio, thus preventing the mower from starting.

– What to Do?

  • Clean the filter: Thoroughly clean the air filter by washing it with a soap and water solution. You should perform this cleaning at least twice every season.
  • Replace the filter: Replace the filter if it’s in bad condition and when cleaning alone isn’t enough.

3. Gummed Up Carburetor 

After checking the air and fuel filters, the next step involved inspecting the carburetor for fuel deposits.

A dirty or clogged carburetor is often another reason the lawnmower won’t start. A blocked-up carburetor fails to maintain the flow of fuel and air reaching the engine, leading to a reduced power output and hence, starting problems. In this case, you should service your carburetor.

– What to Do?

  • Remove the carburetor: Remove the carburetor from the lawnmower. To do that, you must first remove the air filter. Then, remove the fuel lines from the fuel tank while ensuring no fuel spills occur. Afterward, unscrew the mounting bolts to detach the carburetor.
  • Perform the cleanup: You need to clean the carburetor jets using a carb thoroughly. You can use a cleaner spray for this. Make sure all the fuel and air jets are cleaned from deposits. A thin metal wire to remove oil fuel debris can also be helpful. After cleaning, reassemble the carburetor and attach it back to the lawnmower.
  • Assess the carb condition: Check for signs of corrosion within the carburetor. If its condition is worse, it’s best to replace the carburetor to maximize your lawnmower’s performance.

4. Fuel Cap Blockage 

Sometimes, lawnmower startup problems occur due to a vapor lock in the fuel tank. A blockage in the fuel cap vents produces a buildup of fuel vapors within the tank. The high vapor pressure can affect the fuel flow rate to the carburetor.

Remove the fuel cap for a minute to alleviate the pressure buildup and then put it back on. If the lawnmower starts again, the issue was probably due to a vapor lock in the tank. To prevent this in the future, clean the fuel cap vents from dirt using a thin metal wire.

5. Damaged Recoil Assembly

This problem occurs in self-propelled lawnmowers with a rope start mechanism. The recoil assembly is coupled with the engine’s crankshaft via a clutch assembly. When the rope is pulled rapidly, the recoil spring rotates the crankshaft, which starts the engine.

If the pull cord becomes stuck or doesn’t gain tension when pulled, it indicates a fault within the recoil assembly. The spring could be damaged, or the rope could have been stuck.

– What to Do?

  • Remove the plug: Turn off the mower and disconnect the spark plug before inspecting the coil so the engine doesn’t start up accidentally.
  • Remove the blower housing: To access the recoil assembly, unscrew the fasteners mounted on the blower housing and take the recoil assembly out. The recoil assembly is a pulley wound by a spiral spring and a rope.
  • Inspect the damage: Check the recoil assembly for signs of wear and tear. See if the spring winds up correctly. Also, check for broken or missing parts.
  • Replace the parts: Replace the damaged components in the recoil assembly, i.e., worn-out springs, broken pulleys, and ropes. I recommend consulting a professional if you are doing it for the first time.

MTD Riding Lawnmowers: Starting Problems

Here are some common starting problems in MTD riding lawnmowers and their fixes.

1. Riding Lawnmower Does Not Start?

In this case, you should check for the following problems:

– Dead battery:

Check the battery connections. Make sure they aren’t corroded and are still conducting current. If your engine has been sitting for more than three weeks, chances are the battery is dead, and the engine needs to be jumpstarted.  

– Safety switches:

Certain lawnmowers have safety switches that, if not properly engaged, will prevent the engine from starting. So, check to see if all the safety switches and levers are in the right position.

– Carburetor problems:

A carburetor gummed up with fuel debris can cause starting problems. Remove the carburetor and clean it using a cleaner spray or WD-40. Make sure all the jets and passages are clean.

– Spark plug issues:

Check the spark plug for signs of damage, carbon build-up, or worn-out electrodes. Replace the spark plug with a new one.

Typically, the problem is resolved by performing the steps mentioned. If the issue remains, I advise consulting a mechanic.

2. Riding Lawnmower Starts but Then Dies?

If the MTD lawn mower dies immediately after starting, here are potential problems and fixes:

– Fuel problems:

Check that the fuel tank has adequate fuel and that the fuel filter is not blocked. Clean out the fuel filter or replace it if it’s damaged or clogged beyond repair.

– Ignition issues:

Check the ignition coil, the spark plug wires, and any other ignition components for damages and wear. Replace them if they are faulty.

– Air filter problems:

Check if the air filter isn’t clogged with dirt or debris. Wash it with soap and water to ensure continuous airflow to the carburetor and engine.

3. Riding Lawnmower Is Smoking?

If a riding lawnmower smokes, here are the main reasons:

– Oil leakage problems:

Excessive oil consumption may cause white smoke from the mower’s exhaust. This occurs when the oil tank is overfilled, or the lawnmower is tilted in the wrong direction. This causes oil to leak into the cylinder head and burn along with fuel, thus producing smoke.

– Overheating problems:

If the engine is running hot, it can cause the mower to smoke. Make sure the radiator (if any) is filled with coolant and is functional. Avoid overrevving your engine at low gears since this puts excess load, which in turn causes it to overheat.

– Clogged air filter:

A clogged air filter restricts airflow, disrupting the engine’s fuel-air ratio. A fuel-rich mixture can cause black smoke to come out of the exhaust, thus indicating incomplete combustion. In this case, make sure your air filter is clean.

4. Riding Lawnmower Runs Rough/Misfires?

The following issues are probably causing misfires in your lawn mower.

– Spark plug problems:

A faulty spark plug can cause rough runs or misfires in the lawn mower. Remove the spark plug and clean it. If that doesn’t solve the issue, replace it. 

– Fuel quality problems:

Drain out the stale fuel and refill the tank with fresh and clean fuel. Use a fuel stabilizer to increase the duration of fuel freshness.

– Mechanical problems:

Mechanical problems like compression loss, damaged components, or valve issues can cause misfires and rough running. Seek a professional’s help to identify these issues and replace the damaged parts.

5. Does the Riding Lawnmower Has a Dead Battery?

Are you noticing that the mower is frequently and quickly losing battery power? Here’s what you should do.

– Check battery connections:

Check that the battery connections are tight, secure, and clean. Connections that are loose or corroded can cause the battery to die frequently.

– Recharge the battery:

To recharge the battery, you need a 12V DC adaptor. Alternatively, your lawnmower also recharges the battery with an onboard alternator. After running the engine for some time, check the battery voltage with a multimeter.

If the terminal voltage is below 12V, the battery is dead and must be replaced. To prolong your battery life, ensure the electrolyte level is maintained if your battery allows this. Moreover, detaching the battery terminals is recommended before storing it for the winter.

MTD Self-Propelled Lawnmowers: Starting Problems

As with riding lawnmowers, MTD self-propelled lawnmowers may also face trouble starting. Here are the typical starting problems and their fixing procedure:

1. Lawnmower Engine Doesn’t Start

Inadequate fuel in the fuel tank, damage to the spark plug, blocked air filters, and clogged carburetor are some problems that could be preventing the engine from starting.

So, ensure all the filters (air and fuel) are clean. Check for damaged parts and missing components and secure or replace them. Refill the tank with fresh fuel and add a fuel stabilizer to prevent it from decomposing.

2. Lawnmower Pull Cord Doesn’t Work:

The recoil assembly must be examined if the pull cord gets stuck or appears loose. In this case, you must disassemble the recoil housing and check the spiral spring and the pulley.

If the pulley and the spring are fine, the rope is probably stuck, and replacing it would fix the issue. However, if the pulley and the spiral spring are stuck and do not recoil when with the rope, you should replace these components.

Visit a local parts dealer to find replacements. Alternatively, you can also consult a mechanic for these repairs.

MTD Battery Powered Lawnmowers: Starting Problems

Some prefer battery-powered lawnmowers by MTD due to quiet operations and less maintenance needs. However, here are some problems you may face and should be aware of.

1. Battery Powered Lawnmower Doesn’t Start?

Here is what you should do if your battery-powered lawn mower doesn’t power up.

  • Examine the battery: Make sure the battery is fully charged. Also, check if the connections and wires aren’t loose or corroded. Clean or fix them, or replace them when needed.
  • Power Switch: Ensure the power switch is not stuck in the ‘off’ position. Also, examine for a faulty power switch using the continuity test option in a multimeter. If the terminals indicate continuity, the switch is working fine.
  • Safety key: Certain battery-powered mowers have a safety key that must be inserted to start the mower. Make sure that the key is in position when you’re starting.

Typical starting issues in MTD battery-powered lawnmowers are mainly due to low batteries or damaged switches. If the problem isn’t solved by following the mentioned steps, you should get the electric motor checked by the MTD service center.

2. Battery Powered Lawnmower Shuts Down?

If your battery-powered lawn mower suddenly shuts down, here are some common causes:

  • Overheating: If the mower is overheated, it can trigger a safety feature that turns off the mower. Wait for the machine to cool down.
  • Low battery voltage: A low battery percentage will shut down the motor to protect the battery. Make sure the battery is in good condition. If it is old or in bad condition, replace it.

MTD Electric Lawnmowers: Starting Problems

Electric lawnmowers are corded devices that can operate for as long as they are plugged in. Here are some of their common issues:

1. Electric Lawnmower Doesn’t Start?

If your electric lawn mower fails to start, examine the following parts.

  • Start Push Key: Electric lawnmowers have a start push key that powers up the motor. Check to see if it is fully inserted in the keyhole otherwise, the mower will not start.
  • Tripped Circuit Breaker: Check for a tripped circuit breaker in the fuse box if the lawnmower doesn’t start. Remove the plug of your device before switching on the tripped breaker. Reattach the plug and check if the motor starts this time.
  • Faulty Switch/Cord: By plugging it into another socket, check if the switch you’re using isn’t faulty. If you’re using an extension cord, try it without the cord to see if it starts.

2. Electric Lawnmower Keeps Shutting Down?

If your electric lawnmower keeps dying, you must examine the on/off switch and the power cord.

  • Loose Plug: The most typical reason is a loosely inserted socket plug. If your power plug show is loose by default, insert a light plug shoe into the socket.
  • Faulty On/Off Switch: Prolonged usage may have damaged the on/off switch of the mower. Test the switch using a multimeter and replace it if it’s damaged.
  • Broken Power Cord: A damaged cord can affect the current flow to the motor, thus causing it repeatedly shut down. You should contact MTD customer support to get the cord replaced if it’s under warranty.

Lawnmower Starting Problems

1. Gas-Powered Lawnmower Starting Problems

S#
Problem
Causes
Fixes
1
Lawnmower doesn’t start
a. Empty fuel tank
b. Clogged carburetor
c. Air filter blocked with dirt.
d. Spark plug with worn-out electrodes
a. Before adding fresh, drain old fuel residues from the tank.
b. Inspect and clean the air and fuel filters from debris. Replace if necessary.
c. Disassemble and clean the carburetor using a carb. cleaner liquid.
d. Replace the spark plug if electrodes are worn out.
2
Lawnmower starts but then dies
a. Blocked air filter
b. Clogged carburetor jets
c. Vapor lock in the fuel tank
a. Clean the air filter using soap and water. Replace if needed.
b. Clean the carburetor jets from residues using a carb cleaner spray.
c. Clean the fuel tank vents to prevent a vapor lock.
3
Lawnmower is smoking
a. Oil leaking into the combustion chamber
b. Blocked air filter  
a. Avoid overfilling the oil tank.
b. Always tilt the mower with the air filter pointing upwards.
c. Check and replace worn-out gaskets.
d. Clean the air filter.
4
The lawnmower runs rough/misfires
a. Stale fuel deposits in the fuel system.
b. Broken flywheel key
a. Perform a complete tune-up involving cleaning the filters, carburetor, and fuel lines.
b. Replace the flywheel key.

2. Corded Electric Lawnmower Starting Problems

S#
Problem
Causes
Fixes
1
Lawnmower doesn’t start
a. Loose connection
b. Defective extension cord
c. Faulty start switch
d. Tripped circuit breaker
a. Ensure the connections aren’t loose and the socket is working.
b. Try plugging in directly without an extension cord.
c. Test the start switch using a multimeter and replace it if needed.
d. Reset the tripped circuit breaker.
2
The lawnmower shuts down during operation.
a. Loose plug at the socket
b. Tripped circuit breaker
c. Motor winding damage
a. Ensure the connection isn’t loose and the socket works.
b. Reset the circuit breaker or replace the blown switches.
c. Contact customer support to seek a replacement in case of motor damage.

3. Cordless Battery Powered Lawnmower Starting Problems

S#
Problem
Causes
Fixes
1
Lawnmower doesn’t start
a. Low battery
b. Faulty start switch  
a. Ensure the battery is fully charged.
b. Test the start switch for continuity using a multimeter.  
2
The lawnmower shuts down during operation.
a. Low battery
b. Overheating
c. Debris obstructing the blades  
a. Ensure the battery is fully charged.
b. Let the lawnmower cool down for 10-15 minutes and restart.
c. Clean the mower’s underside and remove any debris/grass clippings.

4. Robotic Lawnmower Starting Problems

S#
Problem
Causes
Fixes
1
Lawnmower doesn’t start
a. Disconnected boundary wire
b. Faulty power supply
c. Software update
d. Debris stuck in blades
a. Ensure the boundary wire is connected to the charging station.
b. The battery connections should be correct and the charging should be sufficient.
c. Keep the software up to date.
d. Remove any debris stuck between blades.
2
The lawnmower keeps shutting down mid-operation
a. Ensure the boundary wire is connected to the charging station.
b. The battery connections should be correct, and the charging should be sufficient.
c. Keep the software up to date.
d. Remove any debris stuck between blades.
a. Avoid mowing when the conditions are damp.
b. Resolve error messages on the display.

Leave a comment

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  1. Ricardo Brooks says:

    How often should I clean the air filter of my MTD lawnmower?

    • Allard Vdhooft says:

      To maximize performance, clean the air filter of your MTD lawnmower every season. Make sure to replace if necessary to prevent starting issues and maintain proper airflow for the engine.

  2. Debbie Peck says:

    I appreciate the detailed troubleshooting steps provided for MTD lawnmowers.

    • Allard Vdhooft says:

      Thank you for your feedback, Debbie Peck! I’m glad you found the troubleshooting steps helpful for your MTD lawnmowers. Happy gardening!

  3. Alexa Spencer says:

    What precautions should I take while inspecting the recoil assembly?

    • Allard Vdhooft says:

      To inspect the recoil assembly, check for any damage or wear on the pulley, spring, and rope. Make necessary replacements if needed to ensure proper engine start-up.

  4. Jim Young says:

    I found the video links included in the article very helpful.

    • Allard Vdhooft says:

      Thank you for your feedback, Jim! I’m glad you found the video links helpful. Let me know if there’s anything else you need assistance with.

  5. Carolyn Snyder says:

    Thank you for this informative article! I now have a better understanding of how to troubleshoot starting problems with my MTD lawnmower. Great tips for maintenance!

    • Allard Vdhooft says:

      Thank you, Carolyn! I’m glad you found the article helpful. Remember to regularly maintain your MTD lawnmower to avoid starting problems. Happy mowing!

  6. Brittany Neal says:

    It’s good to know the different starting problems and solutions for MTD lawnmowers.

    • Allard Vdhooft says:

      Thank you, Brittany! I’m glad you found the information helpful for your MTD lawnmower starting problems. Let me know if you have any other questions.

  7. Madison Howard says:

    I always struggled with starting issues on my riding lawnmower, but this article clarified a lot.

    • Allard Vdhooft says:

      Glad to hear the article helped you, Madison! Proper upkeep is key to keeping your lawnmower running smoothly. If you have any other questions, feel free to ask.

  8. Bobby Ray says:

    The section on battery-powered lawnmowers was particularly insightful.

    • Allard Vdhooft says:

      Thank you, Bobby Ray! I’m glad you found the section on battery-powered lawnmowers insightful. If you have any questions or need further information on lawnmower maintenance, feel free to reach out.

  9. Debbie Harrison says:

    Should I use regular fuel stabilizer or is there a specific brand recommended?

    • Allard Vdhooft says:

      For starting problems with your MTD lawnmower, using a fuel stabilizer and regular maintenance is key. Try a stabilizer brand recommended by the manufacturer for optimal results.

  10. Roland Cooper says:

    Can I use any spark plug for my MTD lawnmower or is there a specific type recommended?

    • Allard Vdhooft says:

      For your MTD lawnmower, use a spark plug recommended by the manufacturer to ensure optimal performance and longevity. It’s best to follow their specifications for the best results.

  11. Violet Rivera says:

    What are the signs of a faulty power switch in a battery-powered lawnmower?

    • Allard Vdhooft says:

      To diagnose a faulty power switch in a battery-powered lawnmower, use a multimeter to check for continuity in the switch terminals. If there is continuity, the switch is functional; if not, it may need to be replaced.

  12. Marian Castro says:

    Is it possible to overcharge the battery of a battery-powered lawnmower?

    • Allard Vdhooft says:

      It’s not possible to overcharge the battery of your battery-powered lawnmower. Always follow the manufacturer’s recommendations for charging to ensure optimal performance.

  13. Serenity Ford says:

    This article is very informative for lawnmower owners.

    • Allard Vdhooft says:

      Thank you, Serenity! I’m glad you found the article informative for MTD lawnmower owners. If you have any specific questions or need further assistance, feel free to reach out.

  14. Corey Bell says:

    Good suggestions to keep my MTD lawnmower in good shape!

    • Allard Vdhooft says:

      Glad you found the suggestions helpful for keeping your MTD lawnmower in good shape, Corey! Happy mowing!

  15. Hilda Castillo says:

    I never knew about the significance of cleaning the carburetor in lawnmowers.

    • Allard Vdhooft says:

      Thank you for your comment, Hilda! Regular carburetor cleaning is essential for lawnmowers to prevent starting problems. Maintenance is key for a functional machine.

  16. Charlie Fernandez says:

    Great tips on maintaining and fixing common problems with lawnmowers.

    • Allard Vdhooft says:

      Thank you, Charlie! I’m glad you found the tips helpful for maintaining lawnmowers. Feel free to reach out if you have any more questions or need further assistance.

  17. Jennie Sanders says:

    How frequently should I check the spark plug wires in my riding lawnmower?

    • Allard Vdhooft says:

      For optimal performance, check spark plug wires annually for any signs of wear or damage. This can prevent starting issues and ensure your riding lawnmower runs smoothly.

  18. Lucas Griffin says:

    Do all MTD lawnmowers have safety switches to prevent starting issues?

    • Allard Vdhooft says:

      Yes, all MTD lawnmowers are equipped with safety switches to prevent starting issues. Regular maintenance and troubleshooting can help resolve common problems.

  19. Landon Martin says:

    I’ll be more cautious about fuel maintenance in my lawnmower after reading this.

    • Allard Vdhooft says:

      I’m glad you found the information helpful! Regular fuel maintenance is key to keeping your lawnmower running smoothly. Let me know if you have any other questions.

  20. Bradley Carter says:

    What is the best way to clean a carburetor in an MTD lawnmower?

    • Allard Vdhooft says:

      Regularly cleaning the carburetor in your MTD lawnmower is key to preventing starting issues. Use carb cleaner spray and follow manufacturer guidelines for best results.

  21. Cindy Snyder says:

    Is it common for the fuel cap to get blocked in lawnmowers?

    • Allard Vdhooft says:

      Hi Cindy, sometimes a blocked fuel cap can cause starting issues in lawnmowers. Removing it for a minute to alleviate pressure buildup may help. You can also clean the fuel cap vents to prevent future blockages.

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