Cub Cadet Lawn mower won’t start

Cub Cadet Lawn mower won’t start. You need to mow your lawn again, but your Cub Cadet lawn mower won’t start. Once again, it’s that time of the week again when you need to mow your lawn.

As a lawnmower dealer, I have troubleshot a lot of starting problems with homeowners and commercial customers.

Cub Cadet lawn mowers are prone to not starting for many reasons such as a loose spark plug connection, clogged air filter, bad fuel pump, bad battery, corrosion on electrical components, or dirt in the carburetor.

Cub Cadet Lawn mower won’t startcub cadet lawn mower won't start

Why a Cub Cadet lawn mower won’t start. In order to diagnose the problem, first inspect the spark plug for signs of wear or damage, such as lack of a visible gap.

If it looks good then you’ll need to remove the air filter box off of your Cub Cadet’s carburetor and check for two things: firstly make sure there are no loose parts inside, and that secondly it isn’t clogged with a foreign material such as dirt.

The best way to prevent this from taking place is to periodically drain fuel into a suitable container so as to avoid thickening buildup.

Defective Carburetor

Over time, the filters inside a lawnmower can get clogged with dirt, dust, and other non-combustible materials from the air. Eventually, this may prevent your engine from starting properly.

The float of the carburetor controls how much gasoline flows into the combustion chamber when the piston is on its upward stroke. Sometimes these floats get clogged, which prevents your engine from getting an accurate amount of gasoline so that it can start properly.

The carburetor cleaner will help you to clean out all those little crevices inside the carburetor so that you will be able to get your engine running perfectly again.

Faulty Spark Plugfaulty spark plug

Examine the porcelain insulator for cracks, if the electrodes are damaged or burned away, and if there is a buildup of material at the electrodes.

If you want to make sure that your spark plug is working as it should, you should use a spark plug tester. You should always check for a strong spark between the terminals when cranking the engine.

There may not be a spark present, which indicates that your spark plug needs to be replaced.

Plugged Cub Cadet air filter

Make sure you keep your Cub Cadet’s air filter clean to prevent excessive wear and tear on the engine. If you neglect to change it for weeks at a time, the engine won’t be able to get enough air into it, therefore overheating.

The parts responsible for channeling air can then break down quicker than normal because they will develop cracks from stress and strain.

The best way to avoid this is by ensuring that your Cub Cadet stays in optimal condition via necessary maintenance work at least every 2 months.

Fuel line blocked

Old fuel and dirt can clog up your fuel line. After you’ve drained the gas tank, you can leave the gas tank empty for just a few hours to give it a good chance to air out.

Otherwise, mix some solvents (such as carburetor cleaner) with water in your gas tank to get rid of any stubborn grime that may be clinging onto the walls of your fuel lines.

Use canned air to blast bubbles through the tube until it’s absorbent again. If this doesn’t help, or if it happens frequently, then you might need to just replace your lawn mower’s whole fuel line in order for it not to happen in the future.

Bad Ignition Coilbad ignition coil

An ignition coil is like an extension cord for a lighter. It provides the power that’s needed for the spark plug to fire off so your car engine can start.

The engine won’t ignite if the spark plug can’t fire, and this will cause your car not to run.  After you check to make sure the spark plug is in good condition, try testing out the ignition coil’s continuity with an ohmmeter.

Replace it with a new one if you spot a break in its continuity this could mean that it’s faulty and probably dangerous because your car likely won’t function properly until you replace using a brand new ignition coil.

Starter solenoid failed

An electromagnetic starter switch that is actuated by an on/off button, like the kind in your car, is what allows the Cub Cadet lawn mower engine to turn over.

A clicking or buzzing noise when turning over the ignition key is a good indication that there may be a problem with your starter solenoid. Another good indicator of an issue with your starter solenoid is if you notice wires connected to it are beginning to melt or smoke.

When this happens, you should definitely call for repairs as there could be a serious problem developing inside the Cub Cadet mower engine.

Faulty Charging system

Sometimes, your Cub Cadet doesn’t start because the charging system drains the battery. The problem can be caused by a bad stator or alternator, as well as several other electrical parts.

However, if you think the problem is in your charging system, I suggest you have a small engine mechanic diagnose the charging system for you.

It is possible to spend a lot of money throwing parts at it and making guesses that might not even resolve the problem.

Recoil Spring issue

A starter rope is a key to getting any engine to start. Making sure the recoil spring is in working order is just as important as making sure the starter teeth are aligned.

In the event that the recoil spring breaks, a great method for managing this malfunction and preventing an engine from starting up early is by using a wrench to keep the nut engaged with the teeth.

If this does not prevent it from firing up, another option is to replace both of these parts at once.

Rewind Pulley and Spring problem

There may be a problem with the rewind spring. Reel springs recoil the starter rope onto a pulley/sheave when the starter rope is pulled and released.

Damaged or worn-out springs won’t recoil the starter rope properly. Consequently, the engine may not start. The broken part can be replaced with a new rewind assembly if needed.

Safety Switch and start switch issue

Test for continuity with a multimeter before determining whether either of the safety switches or the start switch is malfunctioning.

Cub Cadet Lawn mower won’t start

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