Category: Riding Lawn Mower Repair

Riding Lawn Mower Repair

Riding Lawn Mower Makes a Thumping Noise When Running

Are you hearing a thumping or vibration type of noise coming from under the lawn mower chassis? Is it a steady noise or does it get worse when you are driving the mower?

Let’s think about this for a minute. When the riding lawn mower is running, the drive belt is turning. The drive belt increases in RPM when you move the throttle up and down. When the throttle is set to lower RPM, the noise might be louder because the engine noise is less and may be less apparent when the RPM is higher.

What most likely is going on is that you have lost a piece out of the drive belt and when it rolls over a pulley, it creates this thumping sound. If you hear multiple thumping sounds, then you know that there are several pieces missing out of the drive pulley.

There could also be a problem such as a bearing is going out on a drive pulley or the pulley itself could have a flat spot in it or a piece broken out of it. Carefully check all the pulleys and bearings and if they are suspect, replace them.

I hope this helps you find out what is causing the thumping noise in your riding lawn mower and that you resolve it. If you need a lawn mower repair shop, visit our Locations page for help today.

Push and Self-Propelled Lawn Mower Repair, Riding Lawn Mower Repair, Zero Turn Lawn Mower Repair

Gas is Leaking From Air Filter on My Mower

Are you seeing gas pouring out of the air filter area on your lawn mowers engine? When you remove the air filter is it soaking wet with gas?

This is a common problem when a lawn mower sits for a long time such as over the winter. Some lawn mowers have a shutoff valve that allows you to turn off the gas and not let the weight of the gas overcome the needle and seat in the carburetor. A needle is the size of a pencil lead and it has to force itself down on the seat to seal off the gas from coming through the carburetor and flooding the engine.

If the needle and seat becomes dirty or gummed up with fuel residue, gasoline will begin to seep past it and come out the throat of the carburetor and thus into the air filter. It will continue until the gas tank is empty and could cause a fire in your garage or shed.

This problem is a safety concern and should be inspected and repaired by a small engine repair shop. You can find one near you by visiting our Locations page.

Riding Lawn Mower Repair

Riding Lawn Mower Cuts Out When it Hits a Bump

You are just cruising along on your riding lawn mower and hit a dip or bump in your yard and the mower just cuts off for a split second. Why? Is there something wrong with the lawn mower or could it be something I am doing?

Well…there is probably nothing wrong with the lawn mower as it is doing what it is supposed to do. When you hit a bump, it causes you to momentarily come off of your seat. When you come off your seat, the seat switch activates and cuts off power to the ignition system to kill the engine.

Why does the seat switch kill the engine? Because it is thinking that you just rolled the lawn mower and it wants to shut down the engine which in turn will stop the lawn mower blades from dicing you up if it rolls over onto you.

The seat switch is a vital part of the safety switch system and unplugging it is a very bad idea safety wise. If the lawn mower rolls over and lands on its wheels and doesn’t die, the mower could continue moving and hit something or someone. I know it is an annoyance when you hear the engine popping, but that switch is there for a reason and make sure that it works as it should.

 

Lawn Mower Repair Tips, Push and Self-Propelled Lawn Mower Repair, Riding Lawn Mower Repair, Zero Turn Lawn Mower Repair

My Lawn Mower Oil Smells Like Gas

It is not uncommon for your lawn mower engine oil to smell like gas. If you have a leaky carburetor needle and seat, the gasoline will seep past it and overflow the carburetor and end up in the cylinder. Once inside the cylinder, it will seep past the piston rings and end up in the crankcase.

What causes this is a buildup of deposits on the needle and seat inside the carburetor. These deposits cause the seal to not work properly and the weight of the fuel pushing on the needle will overcome it and then allow fuel to go past it.

Two things will need to be done to resolve this problem.

The first thing is to completely clean the carburetor. It must be disassembled and cleaned entirely.

The next thing is that the oil must be changed. Warm the engine up for a brief time and then remove the oil and replace it with the proper oil. Synthetic oil is fine to use in your lawn mower engine.

After you have run the engine and changed the oil. Fill the gas tank up and check the oil the next time before you mow to see if you smell any gas or if the oil level is higher than normal. If everything is OK, you should be fine to use your lawn mower.

Riding Lawn Mower Repair

I Press The Go Pedal and Riding Lawn Mower Does Not Move

On many riding lawn mowers, the pedal on the right side is called the “go pedal”. When you press it the riding lawn mower simply goes. Depending on how hard you press it will determine the speed that the lawn mower should go.

When your right foot presses the pedal, the linkage tightens the belt on the pulleys or moves a valve on the transmission to make the riding lawn mower move. In many cases if the lawn mower does not move, it is a belt that has come off of a pulley or has worn out. The linkage could also be sticking or the transmission itself could be experiencing a problem.

It is best to remove the deck to check out this problem so you can have access to the belts and linkages. Remove the deck and that should give you enough clearance to look under the deck. Visually inspect the belt for wear and ensure that the springs and pulleys are all working as they should.

Depress the go pedal and see if the belt becomes tight and if not, you have most likely found your problem. Replace that belt and test the machine to see if it works as it should.

If you need professional assistance, visit our Locations page for a riding lawn mower shop near you.

Riding Lawn Mower Repair

What Does a Riding Lawn Mower Tune-up Consist Of?

So your lawn mower needs a tune-up and you are wonder what they actually should do during that preventive maintenance.

Here is a checklist that I use to ensure my clients get their riding lawn mower serviced properly.

If you need a riding lawn mower shop in your area, check out our Locations page for a shop near you.

Riding Lawn Mower Tune-Up Checklist

  • Document Model Code and Serial Number – Look For Service Bulletins
  • Clean Mower With Leaf Blower Under Hood, Deck, Chassis & Transmission
  • Start Engine – Warm Up – Check Spark – Check All Functions of Mower & Test Drive
  • Test Safety Switches – Brake Test
  • Test Charging System While Running & Battery After Shutdown
  • Change Oil and Filter
  • Check Compression L______R______
  • Remove Hood & Put Rider on Lift
  • Change Air Filter, Fuel Filter & Spark Plugs
  • Clean and Coat Battery Terminals
  • Remove Blower Cover and Clean & Degrease Engine
  • Clean Carburetor if Necessary
  • Inspect Engine for Damage, Wear or Missing Parts
  • Grease Fittings in Steering, Wheels, Axles, Chassis & Deck Spindles
  • Check Front Wheel Bearings & Steering Support Inserts
  • Inspect Electrical, Mechanical and Control Cable Systems
  • Inspect Fuel and Vapor Lines to Tank & Gas Cap
  • Inspect Deck and Drive Belts – Brake Pad
  • Inspect Drive Spindles for Binding or Bearing Wear
  • Inspect Deck Pulley’s and System Parts
  • Lubricate Mechanical Linkages & Control Cables with Dry Lube
  • Remove Blades and Sharpen – Scrape Deck – Install Blades -Torque to Specs
  • Inspect Transmission Oil Level & Cooling Fan ÿ Transmission Mount Brackets
  • Fill Tires With Air – Normally 18psi Front and 10psi Rear
  • Check Tires for Wear & Damage – Check Scalp Wheels for Wear & Damage
  • Level Deck if Necessary

 

Lawn Mower Repair Tips, Push and Self-Propelled Lawn Mower Repair, Riding Lawn Mower Repair, Zero Turn Lawn Mower Repair

Lawn Mower Leaks Oil From Crankcase

Occasionally we see an oil leak from the crankcase gasket that seals the two halves of the crankcase together. Or a pinhole develops in the actual casting of the crankcase and oil will seep out of it. Other areas that leak are protrusions through the crankcase such as the governor arm shaft. Head gaskets can be another source of an oil leak out of the crankcase. An oil seal at the crankshaft is another oil leak source.

Note: Be extra cautious during the testing as you are working near a lawn mower blade. You can shutdown the engine prior to checking for where the engine is leaking for safety.

There are some dyes that can be added to the oil to find a hard to find oil leak. You put the dye in the crankcase and run the engine to get it warmed up. Then a black light is used to identify where the oil leak is coming from.

If you don’t have access to this type of testing paraphernalia, thoroughly clean the engine crankcases and then run the engine until it is warm. Look over the areas that you suspect the leak is coming from and look for the slightest weeping of oil. Wipe the area down and continue to monitor it.  Some leaks are difficult to find, but you will eventually find them.

Lawn Mower Repair Tips, Riding Lawn Mower Repair

My Riding Lawn Mower Cuts Unevenly

Uneven can be a vague term when talking about how your riding lawn mower cuts. Does it scalp the lawn when you turn or cut lower on one side than the other?

Those are two of the most common problems and a third is that the front of the deck cuts more than it should.

Put your riding lawn mower on a flat concrete or gravel surface and visually inspect the deck. Does it lean to the left or right? Is it low in the front and high in the back? Once you determine what the problem is, you can now make adjustments. A tape measure works to adjust the deck from side to side and get it as level as possible. There is a special tool designed for this that measures the height at the blade tips that is available on Amazon or other retailers.

The deck must also be adjusted so the height in the front and rear are correct. A general rule is that there only be 3/4″ difference from front to rear in height. So adjust that accordingly to get the height right.

Are your scalp wheels missing or wearing out? This can cause the deck to scalp the lawn when you make turns. Replace them and the bolts and nuts if they are out of specifications.

These small adjustments can make a world of difference in the look of your yard after you mow, so make them and go test the mower to see if it resolved the problem.

 

Lawn Mower Repair Tips, Riding Lawn Mower Repair

My Riding Lawn Mower Pulls To One Side

It is pretty annoying when your riding lawn mower does not track straight. It either pulls to the left or pulls to the right and never seems to go where you want it to without a fight.

The good news is that this is a solvable problem and I will give you some things to check to correct this problem and get your lawn mower back on track.

The easy thing to check is your tire pressures. A low tire on either side will cause the mower to pull in that direction. So a tire that is going flat on the right side will cause the mower to pull to the right side and you need to keep putting left correction into the steering wheel to keep the mower going straight.

So check all the tire pressures. The front tires are normally around 15psi and the rears are at 10.

Raise the front end up and check axles and bearings. They should feel tight and not have a lot of play in them when you move them back and forth. If they are loose, replace them with new bearings and check that the axles are not damaged with grooves worn in them.

There is a tie rod that can be adjusted as well on one or both wheels. Look at the mower from the front and see which wheel is pointed in or out. Sometimes they are both pointed in the wrong direction and an adjustment will cure this problem. If your tie rods are non-adjustable, they will need to be replaced.

Lastly, check the steering gear to be sure that it is not worn out or slipping in the gears. These gears need lubricated during maintenance to prevent them from wearing out.

These are the most common problems that cause steering issues. Check them one at a time to solve your steering problem in your riding lawn mower.

If you need professional help with your riding lawn mower, visit our Locations page for a shop near you.

Riding Lawn Mower Repair

Riding Lawn Mower Loses Power When the PTO is Engaged

You are all set to cut your lawn and you pull the PTO knob to engage it and the engine starts to bog down and barely runs. Well, that is going to be a problem for sure. If your riding lawn mower doesn’t have the power to mow, you are not going to get much done today.

This problem normally occurs in a twin cylinder engine. One cylinder has developed a problem and is not producing the power that it should. It could be something minor or major depending on what actually happened with the cylinder head. It is not uncommon for a push rod to slip off the rocker arm because the engine never received the required maintenance to ensure that it runs like it should.

One cylinder could not be getting the necessary fuel to keep the engine running as well. Dirt or other debris could be clogging up the main jet or the fuel injector might not be working correctly.  Bad fuel can cause low power or water in it as well. Water in the fuel will make a popping sound out of the exhaust as it is running.

Low power on a riding lawn mower is usually a problem that you want a professional lawn mower repair shop to diagnose and repair for you. Visit our Locations page for a shop near you.