Craftsman M220 Lawn Mower Wont Start

Craftsman M220 Lawn Mower Won’t Start: Complete Troubleshooting Guide

When your Craftsman M220 lawn mower won’t start, it can quickly turn a routine lawn maintenance day into a frustrating experience. This popular 150cc push mower is known for its reliability, but like any mechanical equipment, it can encounter starting problems.

In this comprehensive guide, we’ll walk through the most common reasons why your Craftsman M220 lawn mower won’t start and provide step-by-step solutions to get your mower running again.

Whether you’re dealing with fuel issues, spark plug problems, or carburetor troubles, this troubleshooting guide will help you identify and fix the problem without necessarily requiring professional help.

Key Takeaways

Check fuel quality and level before attempting other fixes
Inspect and clean the spark plug or replace if necessary
Ensure the air filter is clean and unobstructed
Examine the carburetor for clogs or damage
Verify that the primer bulb is functioning correctly
Maintain proper oil levels for optimal engine performance
Follow regular maintenance schedule to prevent starting issues

Quick Answer: Why Won’t My Craftsman M220 Lawn Mower Start?

Your Craftsman M220 lawn mower may not start due to stale fuel, a dirty carburetor, faulty spark plug, clogged air filter, or primer bulb issues. In most cases, these problems can be resolved through simple maintenance procedures like draining old fuel, cleaning components, or replacing worn parts.

Common Reasons Why a Craftsman M220 Won’t Start

One of the most common reasons your Craftsman M220 lawn mower won’t start is related to fuel issues. If you’re having trouble getting your mower going, the first thing to check is your fuel situation.

Old or stale fuel is a primary culprit for starting problems. Gasoline begins to deteriorate after about 30 days, especially if it contains ethanol, which attracts moisture and can lead to separation and gumming in the fuel system. This stale fuel can clog the carburetor and prevent proper combustion.

Here’s what to check regarding fuel issues:

Fuel level: Ensure there’s adequate gas in the tank. It might sound obvious, but many starting issues are simply due to an empty tank.
Fuel quality: If the gas has been sitting in the mower for more than a month, especially over winter, it may have degraded. Drain the old fuel and replace it with fresh gasoline.
Fuel cap ventilation: Check if the fuel cap vent is clogged. A properly venting fuel cap allows air to enter the tank as fuel is consumed. If the vent is blocked, it can create a vacuum that prevents fuel flow.
Fuel lines: Inspect the fuel lines for cracks, kinks, or blockages that might restrict fuel flow to the carburetor.

For persistent fuel-related issues with your Craftsman M220, consider using a fuel stabilizer when filling the tank, especially if you don’t use the mower frequently or before storing it for extended periods. This can prevent fuel degradation and related starting problems.

Spark Plug Issues

The spark plug is crucial for your Craftsman M220’s ignition system, and problems with this component can prevent your mower from starting. A faulty, fouled, or incorrectly gapped spark plug won’t be able to create the spark necessary to ignite the fuel-air mixture in the combustion chamber.

To address spark plug issues:

Locate the spark plug: It’s typically found on the front or side of the engine, connected to a rubber boot with a wire inside.
Remove the spark plug: Use a spark plug socket to carefully remove it.
Inspect the condition: Check for carbon buildup, oil fouling, or damage to the electrode. A healthy spark plug should have a tan or light gray insulator.
Check the gap: Use a gap tool to ensure the electrode gap matches the specifications in your Craftsman M220 manual (typically around 0.030 inches).
Clean or replace: If the spark plug is fouled but not damaged, you can clean it with a wire brush. If it’s damaged or heavily worn, replacement is the better option.

When replacing the spark plug for your Craftsman M220, make sure to use the manufacturer-recommended type, as specified in your owner’s manual. Installing the correct spark plug and properly torquing it (avoid overtightening) will help ensure reliable starting.

Carburetor Problems

The carburetor mixes air and fuel in the proper ratio for combustion, and problems with this component are common reasons why your Craftsman M220 lawn mower won’t start. Over time, especially when using ethanol-blended fuels or after periods of storage, the carburetor can become clogged with varnish and debris.

Signs of carburetor issues include:

Engine won’t start despite having fresh fuel and a good spark plug
Engine starts briefly then dies
Rough running or surging when the engine does start
Excessive fuel consumption or the smell of gas

To address basic carburetor problems:

Clean the exterior: Remove debris and dirt from around the carburetor.
Check for loose connections: Ensure all linkages and connections to the carburetor are secure.
Clean the carburetor: For a basic cleaning, use carburetor cleaner spray on the accessible parts. For more thorough cleaning:
- Carefully remove the carburetor (refer to your manual)
- Disassemble it, noting the arrangement of parts
- Clean all jets, passages, and the float bowl
- Reassemble in the correct order

For severely clogged or damaged carburetors, replacement might be necessary. When dealing with carburetor issues, having the correct Craftsman M220 manual on hand is invaluable for guidance on disassembly and reassembly procedures.

Air Filter Maintenance

A clogged or dirty air filter can significantly impact your Craftsman M220’s ability to start. The air filter prevents dust, grass clippings, and debris from entering the engine, but when it becomes clogged, it restricts airflow and disrupts the air-fuel mixture needed for combustion.

To check and maintain your air filter:

Locate the air filter: It’s typically housed in a plastic or metal cover on the side of the engine.
Remove the cover: Usually secured by clips or screws.
Inspect the filter: A paper filter should be replaced if it’s discolored, torn, or heavily soiled. A foam filter can often be cleaned and reused.
Clean or replace: For foam filters, wash with warm water and mild detergent, then allow to dry completely before applying a small amount of engine oil. Paper filters should be replaced if dirty.
Reinstall properly: Ensure the filter is seated correctly with no gaps around the edges.

Regular air filter maintenance is essential for preventing starting issues. As a general rule, check your air filter every 25 hours of operation or at least once per mowing season. In dusty conditions, more frequent checks may be necessary.

If your Craftsman M220 lawn mower won’t start even after air filter maintenance, the issue might be related to other components. However, a clean air filter is a prerequisite for addressing more complex starting problems.

Primer Bulb Functionality

The primer bulb on your Craftsman M220 lawn mower plays a crucial role in starting, especially when the engine is cold. It injects a small amount of fuel directly into the carburetor, creating a richer fuel mixture that’s easier to ignite during startup. If your Craftsman lawn mower won’t start with no primer response, this component might be the culprit.

Common primer bulb issues include:

Cracked or damaged bulb: Over time, the rubber can degrade, crack, or become brittle from exposure to UV rays and fuel.
Internal blockage: Dirt or debris can clog the small passages in the primer system.
Improper priming technique: Not pressing the bulb enough times (typically 3-5 presses) or pressing too aggressively.

To check and address primer bulb problems:

Visual inspection: Look for visible cracks, hardening, or distortion in the primer bulb.
Functionality test: When pressed and released, the bulb should resist slightly, then return to its original shape. If it doesn’t provide resistance or doesn’t return to shape, there may be an issue.
Replacement: If damaged, the primer bulb will need replacement. This is typically an inexpensive part but may require some disassembly of the air filter housing or carburetor cover.

When using the primer bulb correctly, press it slowly and fully, allowing it to return completely between presses. In colder weather, more primes might be necessary, but be careful not to over-prime, as this can flood the engine and make starting more difficult.

For persistent primer issues, consulting the Craftsman M220 manual can provide model-specific troubleshooting advice. If your lawn mower starts then dies shortly after, this could indicate a primer system that’s not functioning optimally.

Ignition System Troubleshooting

Beyond the spark plug, other components of the ignition system can cause starting problems in your Craftsman M220 lawn mower. The ignition system generates the electrical spark that ignites the fuel-air mixture, and failures in this system will prevent starting.

Key ignition system components to check include:

Ignition coil: This transforms low voltage into the high voltage needed for the spark plug. A faulty coil can cause intermittent starting issues or complete failure.
Flywheel key: This small metal piece synchronizes the flywheel with the crankshaft. If it’s sheared (often from hitting an object), the timing will be off, making starting difficult or impossible.
Stop switch/wire: Ensures the ignition circuit is complete when you want to start the mower. A damaged wire or switch can prevent the engine from getting spark.
Ignition module: Controls the timing of the spark. When it fails, the engine won’t start.

Testing the ignition system:

Spark test: Remove the spark plug, reconnect it to the spark plug wire, and ground the threaded portion against the engine. Pull the starter cord and look for a blue spark between the electrodes. No spark indicates an ignition system problem.
Continuity testing: Using a multimeter, check for continuity in the stop switch and associated wiring. This requires some electrical knowledge.
Inspect the flywheel key: Remove the flywheel to check if the key is sheared or damaged. This is a more advanced repair that might require special tools.

If you’re comfortable with moderate mechanical work, you can attempt these tests yourself. Otherwise, ignition system problems might be best addressed by a small engine repair professional who can accurately diagnose and repair these more complex issues.

Oil Level and Quality Impact on Starting

Although not as commonly discussed as fuel or spark issues, improper oil levels or poor oil quality can prevent your Craftsman M220 lawn mower from starting. Most modern lawn mowers, including the Craftsman M220, have oil level sensors or switches that prevent the engine from starting if the oil level is too low, protecting it from damage.

Here’s how oil can affect starting:

Low oil level: Triggers safety shutoff switches that prevent starting
Overfilled oil: Can cause hydraulic lock, fouled spark plugs, and excessive smoking
Contaminated oil: Reduces lubrication effectiveness and can cause internal damage over time
Incorrect oil type: Using oil with the wrong viscosity can affect engine performance, especially in extreme temperatures

To check and maintain proper oil:

Ensure the mower is level: Place your Craftsman M220 on a flat surface before checking oil.
Locate the oil fill cap/dipstick: Usually yellow or orange on most lawn mowers.
Check the level: Remove the dipstick, wipe it clean, reinsert fully, then remove again to check the level. It should be between the “Add” and “Full” marks.
Inspect oil quality: Fresh oil should be amber and translucent. Dark, opaque, or gritty oil needs changing.
Use the correct type: Most Craftsman mowers use SAE 30 or 10W-30 oil, but check your specific model’s manual for recommendations.

Regular oil changes (typically every 25-50 hours of operation or at least once per season) help maintain your mower’s starting reliability and overall performance. If your Craftsman M220 won’t start after winter, an oil change should be part of your spring maintenance routine.

Seasonal Maintenance Tips to Prevent Starting Issues

Preventive maintenance is the best way to avoid starting problems with your Craftsman M220 lawn mower. Seasonal care, especially before and after storage periods, can significantly reduce the likelihood of encountering issues when you need your mower the most.

Pre-Season Preparation (Spring)

Before the mowing season begins:

Change the oil: Start fresh with clean oil appropriate for your model.
Replace the spark plug: Even if it’s not completely worn, an annual spark plug replacement is inexpensive insurance against starting problems.
Clean or replace the air filter: Ensure unrestricted airflow from the beginning.
Drain old fuel and add fresh gasoline: If you didn’t drain the tank before winter storage, do it now. Add fresh fuel with a stabilizer.
Clean the underside of the mower deck: Remove any compacted grass or debris.
Check the blade: Ensure it’s sharp and properly balanced.
Test all safety systems: Make sure blade engagement, safety bails, and other safety features work correctly.

During-Season Maintenance (Summer)

Throughout the active mowing season:

Keep the air filter clean: Check it every 10-25 hours of operation.
Maintain fuel quality: Use fuel within 30 days, or add stabilizer for longer periods.
Check oil level before each use: Top up as needed.
Clean the mower after each use: Remove grass clippings to prevent moisture buildup.
Tighten loose fasteners: Vibration can loosen bolts and screws over time.

End-of-Season Care (Fall/Winter)

Before storing your mower for extended periods:

Run the engine until it’s out of fuel or add fuel stabilizer to a full tank.
Change the oil: Don’t leave dirty oil sitting in the engine during storage.
Remove the spark plug: Add a small amount of oil to the cylinder, pull the starter cord a few times to distribute it, then reinstall the plug.
Clean thoroughly: Remove all debris, especially from cooling fins and under the deck.
Store in a dry, protected area: Ideally indoors, away from moisture and extreme temperatures.

Following these seasonal maintenance tips will greatly reduce the chances of encountering starting problems with your Craftsman M220 lawn mower and extend its overall lifespan. Remember, most starting issues are preventable with proper routine care.

Advanced Troubleshooting for Persistent Starting Problems

If you’ve gone through the basic troubleshooting steps and your Craftsman M220 lawn mower still won’t start, it’s time to consider some more advanced potential causes. These issues might require more technical knowledge or tools, but understanding them can help you decide whether to tackle the repair yourself or seek professional help.

Compression Testing

Proper compression is essential for engine starting and operation. Low compression can be caused by worn piston rings, damaged valves, or a blown head gasket.

To check compression:

Remove the spark plug
Insert a compression tester into the spark plug hole
Pull the starter cord several times
Check the reading against specifications (typically 60-80 PSI for most lawn mower engines)

Low compression usually indicates significant internal engine wear that might require professional repair or engine replacement.

Valve Adjustment

Improper valve clearance can prevent your Craftsman M220 from starting. Over time, valves can become too tight or too loose, affecting compression and the engine’s ability to draw in fuel and air.

Signs of valve issues include:

Difficulty starting
Loss of power
Unusual tapping noises when running

Valve adjustment requires specific tools and some mechanical knowledge. The procedure involves:

Removing the valve cover
Rotating the engine to the correct position
Measuring clearances with feeler gauges
Adjusting as necessary according to specifications

Electrical System Diagnostics

Electrical problems beyond the spark plug can also prevent starting. These might include:

Faulty safety switches: Modern mowers have multiple safety interlocks that must be engaged for starting
Wiring issues: Damaged or disconnected wires can interrupt the ignition circuit
Battery problems: For electric-start models, a weak or dead battery will prevent starting
Starter motor failure: In electric-start models, a faulty starter motor won’t crank the engine

Diagnosing electrical issues often requires a multimeter to test continuity and voltage at various points in the system. If you’re not comfortable with electrical testing, this might be an area where professional help is warranted.

When facing persistent starting issues with your Craftsman M220 not starting, consider whether the mower’s age and condition justify extensive repairs. Sometimes, especially with older mowers that have multiple issues, replacement might be more economical than repair.

FAQ: Common Questions About Craftsman M220 Starting Problems

What would cause a Craftsman lawn mower not to start?

The most common causes include stale fuel, dirty carburetor, faulty spark plug, clogged air filter, defective primer bulb, or low oil level (if equipped with oil sensor). Electrical issues like broken safety switches or ignition problems can also prevent starting. Regular maintenance and proper storage can prevent most of these issues.

What is the first thing to check if a lawn mower won’t start?

Start by checking the fuel—ensure the tank contains fresh gasoline and the fuel valve is open. Next, examine the spark plug for signs of fouling or damage. These two quick checks can identify the most common starting issues and are relatively easy to address without special tools or expertise.

Why is my Craftsman M220 mower turning over but not starting?

If your mower is turning over (the engine is cranking) but not starting, the most likely culprits are fuel delivery or ignition problems. Check that fuel is reaching the carburetor, the spark plug is functioning properly, and the air filter is clean. A clogged carburetor jet or incorrect choke position could also cause this symptom.

How do I fix a flooded Craftsman M220 engine?

To fix a flooded engine, remove the spark plug, turn the mower so the spark plug hole faces downward to drain excess fuel, wait 10-15 minutes, then reinstall a dry spark plug. Alternatively, hold the throttle in the “full” position while cranking the engine several times to clear excess fuel without removing the plug.

Why does my Craftsman M220 start then die immediately?

This typically indicates a fuel delivery problem after initial ignition. Common causes include a partially clogged carburetor that allows enough fuel for starting but not sustained running, improper choke operation, or air leaks around the carburetor gaskets. Check the primer bulb function and ensure the fuel cap is venting properly.

How long should I press the primer bulb on my Craftsman M220?

Generally, press the primer bulb slowly and completely 3-5 times when the engine is cold. Pressing too many times can flood the engine, while insufficient priming may not deliver enough fuel for starting. In cold weather, you might need additional primes, but avoid excessive priming, which can flood the carburetor.

Can old gas prevent my Craftsman M220 from starting?

Yes, gasoline begins to deteriorate after about 30 days, especially fuel containing ethanol. Old gas can leave deposits that clog the carburetor and fuel system. Always drain old fuel before storage and use fresh gas at the beginning of the mowing season, preferably with a fuel stabilizer added if the mower won’t be used frequently.

Final Words: Keeping Your Craftsman M220 Reliably Starting

Maintaining your Craftsman M220 lawn mower for reliable starting doesn’t have to be complicated. Most starting issues can be prevented through regular maintenance and proper care. By understanding the common reasons why your Craftsman M220 lawn mower won’t start, you can quickly diagnose and resolve problems, saving time and potentially expensive repair costs.

Remember to perform routine maintenance tasks like changing the oil, replacing the spark plug annually, keeping the air filter clean, and using fresh fuel with stabilizer. These simple steps go a long way in preventing the frustration of a mower that refuses to start when you need it.

If you’ve tried the troubleshooting steps in this guide and continue to experience starting problems, consider consulting with a small engine repair professional. Sometimes, an expert opinion can identify less obvious issues that might be affecting your mower’s performance.

By following the advice in this guide, you’ll be well-equipped to keep your Craftsman M220 lawn mower starting reliably for many mowing seasons to come.

Craftsman M220 Lawn Mower Wont Start