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MTD Lawnmower Drive & Cutting Problems: Troubleshooting with Fixes

Most users value MTD lawnmowers for their ease of operation and affordability. However, the lawnmower may encounter problems when it’s not maintained correctly. Most typical problems are the ones that occur with the driving mechanism or the cutting blades. Let’s learn how to resolve them in this article.

MTD Lawnmower Drive & Cutting Problems:

If the cutting performance of your MTD Lawnmowers has declined, always check the blades first. Typical issues include blunt edges, blade wear, loosely placed blades, and an uneven mowing deck. Your lawnmower may vibrate or stop moving forward if the drive belt is worn out, loose, or fractured, thus affecting power distribution.

Whether you are a rookie or a seasoned user, follow the step-by-step approach in this article to keep your MTD lawnmower running smoothly.

MTD Lawnmowers: Troubleshooting Cutting Problem

Lack of timely maintenance of the mowing deck and blades may cause cutting problems in riding and pushing lawnmowers. Let’s discuss these problems:

1. MTD Lawnmower Does Not Cut Straight

Here are some of the reasons why your lawnmower doesn’t cut straight patterns of grass:

a. Unequal Tire Pressure: 

It is essential to inspect tire pressure before examining any other component. A low tire pressure is one of the many potential reasons for an uneven cut. When pressure is low in any one tire, the deck will not be level and will sit lower on that side.

Use a tire pressure gauge to check your tires’ pressure according to the sidewall instructions.

If the problem remains, follow the next step.

b. Dull or Worn Mower Blades: 

Your blade tips may become so worn that a strip of grass is left between them when they rotate beneath the mower deck. The sail of your blade may also begin to appear worn. When this happens, your blade cannot generate the airflow and suction required for a successful cut.

Prolonged exposure to dirt causes wear and tear on the blades. Hence, your blade’s edges may become dull and rounded because of excessive wear. In this situation, you should remove the blades and sharpen them. A bench grinder is often used to sharpen lawnmower blades.

If sharpening doesn’t solve the problem, proceed to the next step.

c. Unbalanced Blades: 

An unbalanced blade has one side heavier than the other. This may happen due to uneven wear or when sharpening removes more metal from one side of the blade than the other. If your blade is rough, it may wobble as it rotates.

Due to its high speed, the blade vibrations could damage the spindle bearings. To check this, use a blade balancer to check the balance of your lawnmower blade before installation. If you don’t have one of these tools, you can hang your blade from a nail in the wall to check whether it is balanced.

If the blade balance is off, replacing this blade with a new one is best.

d. Defective Spindle Bearing: 

If you have a damaged spindle or a bad bearing, your blade may wobble while rotating under the deck, producing a squeaking sound and an uneven cut.

To confirm if the blades are unbalanced, check for a knocking sound by pressing one end and rocking it back and forth. When you notice some play or hear a sound, it usually indicates that the spindle bearing is likely to be faulty.

You may need to remove your mower’s blade and spindle housing to check for bearing or spindle damage. Replace any damaged parts. If you’re new to this, ask a professional for help.

2. MTD Lawnmower Cuts Uneven Grass Patterns?

Uneven grass growth makes your lawn look unkept and shows that your mower is not cutting correctly. This issue could be caused by the following:

  • Dull blades: If the blades seem dull or blunt at the edges, you should sharpen or replace them.
  • Incorrect Cutting Height: Adjust the height of the deck to make it uniform on all sides. Ensure this by using adjustment screws and a level gauge. According to the manufacturer’s instructions, correctly set the cutting height and ensure uniformity throughout the deck.
  • Deck Belt Wear: The cutting may be uneven if the deck belts are worn out. This can cause the mower to vibrate while moving. You should inspect the belts underneath the deck and replace them if worn out.
  • Uneven Grass Patterns: Fluctuating mower speeds can lead to uneven grass patterns. Try to maintain a constant and even pace while you operate the lawn mower. Try to avoid rushing or suddenly slowing down when mowing.

3. MTD Lawnmower Doesn’t Cut at All?

Here are the steps needed to be taken if your lawnmower doesn’t cut any grass at all.

a. Check the Blade Lever

The first thing to confirm is whether the blade engagement lever is pressed. The blade engagement lever pulls the blade clutch cable to spin the blades. The blades won’t turn and thus won’t cut the grass if the lever is not engaged.

In some cases, it can also get jammed due to debris or grass clipping jamming the clutch cable. To fix this, disassemble the lever and clean the underside of the mower deck thoroughly to remove any grass.

b. Worn-Out Blade Belt 

A worn-out belt may not grip the pulley that drives the spindle, which will prevent the blades from cutting any grass. This could also generate vibrations or jerks that could produce uneven cuts. To prevent this, always check the blade belt periodically, and replace it when it wears out.

c. Locked Up Mandrel Assembly

The mandrel assembly attached to the deck spins the blade to cut the grass. The blade won’t move if the mandrel locks up. Moreover, a broken mandrel could also lead to uneven cutting and vibrations of the mower deck.

After performing a routine inspection of the mandrels, check if they need any replacements. Except if you know what to do, I recommend hiring a professional to disassemble and replace the mandrel assembly.

MTD Riding Lawnmowers: Troubleshooting Drive Problems

In riding lawnmowers, issues in the drive belt or the gearbox transmission most commonly produce drive-related problems. The most common problems are listed for riding lawnmowers.

1. MTD Lawnmower Doesn’t Move Forward?

For the following causes, your MTD riding lawnmower might not be moving forward:

a. Check the Drive Belt:

The drive belt differs from the blade belt. It operates the axle pulley, which turns the wheels and makes the lawnmower move. Over time, the drive belt could wear down and become loose. As a result, the power transfer to the wheels is affected. Reinstalling a new belt in its place can resolve the issue.

b. Look for Transmission Issues:

A lack of hydraulic oil in a hydrostatic transmission can result in the transmission’s failure. Therefore, be sure to replenish the oil timely. In manual ones, the gearbox assembly may experience mechanical problems. I suggest you employ a professional to complete this repair since it involves removing and disassembling the gearboxes.

2. Does the MTD Lawnmower Vibrates Excessively?

Excessive vibrations can be caused due to: 

a. Imbalance or Damage:

Inspect the blade visually and check if it’s balanced by supporting it at its center. Unbalanced blades vibrate at higher RPMs, and these vibrations can result in other problems in your machine. The best way forward is to replace the blade.

b. Loose Engine Mount:

If the engine mount is loose, the lawnmower may shake more than usual due to excessive engine vibrations. To reduce vibrations, check if all the mounts are tight and none are missing.

c. Crankshaft Damage:

Prolonged engine mishandling can cause the crankshaft to get damaged, which can produce excessive vibrations throughout the lawnmower. In this case, I recommend having the MTD service center replace or repair the engine.

3. MTD Lawnmower Has Loose Steering

If the steering is loose, your lawnmower will be challenging to maneuver and control. To fix the issue, the following steering components must be inspected:

a. Steering Linkage:

Examine the steering linkage, tire rods, and steering wheel for any wear or damage. Tighten any loose connections if you can. Ensure that each component is well lubricated.

I recommend consulting a professional for these repairs if disassembly is required.

b. Shaft adjustment:

If feasible, tighten the steering shaft to ensure no play between the steering and the shaft.

Note: Consult a technician if this is your first time undertaking these repairs.

4. MTD Lawnmower Has a Flat Tire

A flat tire can put your riding lawnmower to a halt until it’s repaired. Here’s how you tackle this problem:

  • Locate the Puncture Site: Inflate the tire with air and place it in a tub of water. Remove it and check if you notice any air bubbles leaking out. This is the puncture site at your tire.
  • Fix the Puncture: You can buy a puncture repair kit to fix the damaged site. Apply the patch and add some pressure on the tire while keeping it for around 20 minutes.
  • Inflate the Tire: After the patch is applied, inflate the tire again up to the recommended pressure rating marked on the tire.

5. MTD Lawnmower Is Leaking Oil

If a lawnmower leaks oil, it’s probably due to a damaged engine gasket. Sometimes, a faulty drain plug can also cause the oil to spill out.

Gaskets are seals between the engine block and the cylinder head. The engine block is where the piston assembly is present, while the cylinder head houses the valves and the spark plugs. To keep the engine oil away from the cylinder head, gaskets are used.

These gaskets are prone to undergo rapid thermal expansion and contraction, which can contribute to wear and tear over time. When your MTD lawnmower is running hot, it will experience excess wear. Once the gasket becomes faulty, oil leaks can be seen from the engine.

Another cause of an oil leak is a worn-out drain plug often found under the oil tank. When the plug gets damaged, oil leaks out, and this can be confirmed by small oil puddles formed under the oil tank.

Avoid tipping your lawnmower to the side with its air filter pointing downwards. This causes oil to flood the air filter, and it leaks out of it. Furthermore, always keep the oil tank up to 3/4th of the maximum level. Overfilled tanks cause the oil to spill out, and thus it may resemble a leak.

MTD Self-Propelled Lawnmowers: Troubleshooting Drive Problems

Like riding lawnmowers, self-propelled lawnmowers propel themselves forward, with the user only required to provide steering control in the desired direction. The following are the most common drive problems in MTD self-propelled lawnmowers:

1. Self-Propelled Lawnmower Doesn’t Go Forward

Here’s what you can do to fix this problem.

a. Engage the Drive Control:

The lawnmower will not move forward if the drive control lever or button is not engaged or positioned correctly. After engaging the lever, check if the issue is fixed. If not, move to the next step.

b. Driver Belts:

A worn, loosened, or broken drive belt might need to be replaced to improve the lawnmower’s drive performance. Check for any signs of slackness or damage on the belt. Tighten the belt if needed. You should get a new belt if the old one is worn out or damaged. If the problem persists, proceed next.

c. Examine the Wheels: 

If the problem isn’t resolved, examine the wheels and see if there’s any mud dislodged between the wheels and axle. Clean the wheels and the axle from debris and grass clippings. Ensure the wheels aren’t loose at their attachment and can rotate freely.

2. Self-Propelled Lawnmower Throttle Not Working

The throttle lever governs the engine speed by controlling the throttle cable. If the lever doesn’t provide the desired function, follow the steps below:

a. Throttle Cable:

The cable connects the throttle control and carburetor to the engine. It regulates how much fuel and air mixture enters the engine for combustion; a higher flow rate increases the power output.

If the throttle is not working, first begin with the throttle lever. If the lever doesn’t press, it indicates the throttle cable is stuck.

Try adjusting the cable manually and see if it works. Try using a bit of lubricant to check if the cable gets fixed. If nothing works, you should get your throttle cable replaced. This will solve the problem.

b. Carburetor:

In some situations, the throttle cable works just fine. However, the engine speed doesn’t seem to change even when the throttle is pressed. This indicates that the fault lies somewhere in the carburetor.

Check for any old fuel debris in the carburetor jets and clean them thoroughly to see if the problem is resolved. To clear out any accumulation of dirt, use a carburetor cleaner. Clean the float bowl and the bowl nut with a carb cleaning spray after disassembling the carburetor.

After cleaning the carburetor and attaching it back to the lawnmower, check the throttle lever again and see if the engine speed changes this time. Most probably, the problem would be fixed. If it isn’t, consult a professional to perform troubleshooting within the engine.