Blog

How To Install Oil Into A Lawn Mower Engine

2024-10-22T11:53:00-05:00

Proper oil installation is recommended to extend the life of your engine. Over-filling or under-filling your engine's crankcase with oil can cause permanent damage to important components within the engine. In this video, Pete will instruct you how to properly fill and check your oil level within the engine.

Here's a quick recap of the video:

Installing Engine Oil

Always use your manufacturer's factory recommended motor oil. Most lawn mower engines require 10W-30, however, please consult your service manual or a servicing dealer for the correct oil specifications for your engine.
Don't put the entire quart into the engine. There are many different styles of small engines that require different quantities of oil. For the correct amount of oil, either check your owner's manual or fill slowly while checking the oil level frequently. Remember that it is nearly impossible to drain every drop of oil out of the crankcase when draining the oil so even measuring the correct fill size will not work.
Helpful Tip: Remember that bubbles and air pockets can form as you pour the oil into the oil fill tube. Allow the oil to settle before checking the level. Push the dipstick down into the filler tube a few times, then remove the dipstick and clean it off with a clean rag or paper towel. Then, put the dipstick down into the tube, hold it for a few seconds, then remove and check the oil level.
Because we're adding new oil, the dipstick can sometimes be hard to read. On many dipsticks, there is a patterned side and a smooth side -- you may need to turn the dipstick to the smooth side and angle it into the light to see where the oil is on the dipstick.
As stated before, over-filling or under-filling an engine crankcase can cause serious damage to an engine. Over-filling can cause the engine to blow out seals which can be a costly repair. Under-filling can cause a lack of lubrication which could result in seizing the engine or having a rod blow out of the side of the engine. We don't want to hear about either of those things, so let's make sure we check always check our oil before using a piece of equipment!

Here's a quick recap of the video:

Installing Engine Oil

Always use your manufacturer's factory recommended motor oil. Most lawn mower engines require 10W-30, however, please consult your service manual or a servicing dealer for the correct oil specifications for your engine.
Don't put the entire quart into the engine. There are many different styles of small engines that require different quantities of oil. For the correct amount of oil, either check your owner's manual or fill slowly while checking the oil level frequently. Remember that it is nearly impossible to drain every drop of oil out of the crankcase when draining the oil so even measuring the correct fill size will not work.
Helpful Tip: Remember that bubbles and air pockets can form as you pour the oil into the oil fill tube. Allow the oil to settle before checking the level. Push the dipstick down into the filler tube a few times, then remove the dipstick and clean it off with a clean rag or paper towel. Then, put the dipstick down into the tube, hold it for a few seconds, then remove and check the oil level.
Because we're adding new oil, the dipstick can sometimes be hard to read. On many dipsticks, there is a patterned side and a smooth side -- you may need to turn the dipstick to the smooth side and angle it into the light to see where the oil is on the dipstick.
As stated before, over-filling or under-filling an engine crankcase can cause serious damage to an engine. Over-filling can cause the engine to blow out seals which can be a costly repair. Under-filling can cause a lack of lubrication which could result in seizing the engine or having a rod blow out of the side of the engine. We don't want to hear about either of those things, so let's make sure we check always check our oil before using a piece of equipment!

How To Replace A Spark Plug & Air Filter On A Honda Mower

2024-10-22T11:53:00-05:00

To obtain the best life out of your engine, make sure you check the air filter for built-up dirt or debris. A dirty air filter can allow the filter to let sediment and debris pass through and into the engine. Dirt ingestion can damage an engine fairly quickly, so make sure you always have an air filter equipped and check to make sure it's clean.

Here's a quick recap of the video:

Replacing The Air Filter

On this particular Honda lawn mower, you'll need to carefully push down on the two retaining clips on the outside of the air filter cover. There are two hinges on the bottom of the air filter cover, carefully clear the hinges from the clips and remove the air filter and air filter "box" (or cover).
It's a good idea to clean the air filter cover and the box before re-installing your replacement air filter.
Place the new air filter back onto the mower in the same direction as the old filter. On this Honda lawn mower, we're going to replace the filter with the fins pointed outward.
Place the hinges back into the pins and snap the air filter cover back into the retaining clips

Replacing Your Spark Plug

Disclaimer (because we have to): Always make sure your engine is off before performing engine maintenance. We want you to start and finish this job with the same appendages God gave you.
The spark plug is traditionally located on the front of the lawn mower. On this Honda lawn mower, it is located in the upper front hand portion of the mower, directly beneath the red engine shroud/cover.
Carefully put your index finger in between the engine and the cap. To remove the cap, grasp the cap firmly, pulling and twisting at the same time to remove the rubber cap. It will eventually slide off. Sometimes the cap can be stubborn, but be patient and it will eventually come off.
We recommend using a spark plug socket. This is a special socket with a rubber seal that grips the spark plug while removing it. The Honda mower we're working on today uses a 13/16" socket.
Carefully remove the spark plug using a socket wrench. We also recommend using a socket wrench extension to make your job easier -- turning a socket in close proximity to the engine shroud can be difficult.
Before installing the new spark plug, check the spark plug gap/clearance for the electrode air gap. This can be obtained from your local servicing dealer or from your machine's owner's manual or service manual.
It's a good idea to lightly oil the threads of the spark plug before installation. This will help you remove the spark plug on your next tune-up.
Always start by hand tightening your spark plug into the cylinder. You do not want to use your wrench to start your spark plug as this may damage the threads on the cylinder head -- this is a costly repair!
When re-installing the spark plug cap, you'll want to take the cap and firmly push the cap over the plug. You should hear it snap into place.

Here's a quick recap of the video:

Replacing The Air Filter

On this particular Honda lawn mower, you'll need to carefully push down on the two retaining clips on the outside of the air filter cover. There are two hinges on the bottom of the air filter cover, carefully clear the hinges from the clips and remove the air filter and air filter "box" (or cover).
It's a good idea to clean the air filter cover and the box before re-installing your replacement air filter.
Place the new air filter back onto the mower in the same direction as the old filter. On this Honda lawn mower, we're going to replace the filter with the fins pointed outward.
Place the hinges back into the pins and snap the air filter cover back into the retaining clips

Replacing Your Spark Plug

Disclaimer (because we have to): Always make sure your engine is off before performing engine maintenance. We want you to start and finish this job with the same appendages God gave you.
The spark plug is traditionally located on the front of the lawn mower. On this Honda lawn mower, it is located in the upper front hand portion of the mower, directly beneath the red engine shroud/cover.
Carefully put your index finger in between the engine and the cap. To remove the cap, grasp the cap firmly, pulling and twisting at the same time to remove the rubber cap. It will eventually slide off. Sometimes the cap can be stubborn, but be patient and it will eventually come off.
We recommend using a spark plug socket. This is a special socket with a rubber seal that grips the spark plug while removing it. The Honda mower we're working on today uses a 13/16" socket.
Carefully remove the spark plug using a socket wrench. We also recommend using a socket wrench extension to make your job easier -- turning a socket in close proximity to the engine shroud can be difficult.
Before installing the new spark plug, check the spark plug gap/clearance for the electrode air gap. This can be obtained from your local servicing dealer or from your machine's owner's manual or service manual.
It's a good idea to lightly oil the threads of the spark plug before installation. This will help you remove the spark plug on your next tune-up.
Always start by hand tightening your spark plug into the cylinder. You do not want to use your wrench to start your spark plug as this may damage the threads on the cylinder head -- this is a costly repair!
When re-installing the spark plug cap, you'll want to take the cap and firmly push the cap over the plug. You should hear it snap into place.

How To Clean the Air Vanes of Your Mower Engine

2024-10-22T11:53:00-05:00

Cleaning the air vanes and flywheel fan are one of the most overlooked items when performing service -- but we'll show you how to do it! Because the majority of small engines on outdoor power equipment are air-cooled, it's important to make sure that these engines have clean air vanes for the air intake. In this video, we'll ensure that our engine is going to cool properly by removing the recoil starter and then the engine shroud. We'll then clean underneath the shroud and then put everything back together.

Here's a quick recap of the video:

Cleaning The Flywheel & Fan Housing

We'll have to remove the recoil assembly to access the air vanes on this mower. To remove the recoil assembly, we'll need to remove the three nuts. Always remember to put your hardware in a safe place, such as on a bench, rag or a tin.
Once we've taken the nuts off, we can lift up on the recoil and set it aside. It will still be attached to the mower by the rope, so do not let this fall or break.
Pull up on the engine shroud to reveal the flywheel and air vans. You'll want to pick up and remove any dirt or debris (such as grass or leaves) from the top of the fan.
It's also a good idea to blow out the air vanes of the cylinder to ensure that there are no foreign objects that could hinder air flow. We recommend obtaining a compressed air "gun" like ours. You'll want to take special care to get air into those pockets and make sure they're clean.
Remember: The cleaner your engine is, the cooler it will run. Keeping it cool will extend the life of your engine.
Put the shroud assembly back on top of the engine and push firmly so that it does not wobble. Then, place the recoil assembly back over the shroud exactly the same way that it was removed. Take your hardware and hand tighten the nuts over the bolts. Use your ratchet to tighten them until they are snug -- do not over-tighten!

Here's a quick recap of the video:

Cleaning The Flywheel & Fan Housing

We'll have to remove the recoil assembly to access the air vanes on this mower. To remove the recoil assembly, we'll need to remove the three nuts. Always remember to put your hardware in a safe place, such as on a bench, rag or a tin.
Once we've taken the nuts off, we can lift up on the recoil and set it aside. It will still be attached to the mower by the rope, so do not let this fall or break.
Pull up on the engine shroud to reveal the flywheel and air vans. You'll want to pick up and remove any dirt or debris (such as grass or leaves) from the top of the fan.
It's also a good idea to blow out the air vanes of the cylinder to ensure that there are no foreign objects that could hinder air flow. We recommend obtaining a compressed air "gun" like ours. You'll want to take special care to get air into those pockets and make sure they're clean.
Remember: The cleaner your engine is, the cooler it will run. Keeping it cool will extend the life of your engine.
Put the shroud assembly back on top of the engine and push firmly so that it does not wobble. Then, place the recoil assembly back over the shroud exactly the same way that it was removed. Take your hardware and hand tighten the nuts over the bolts. Use your ratchet to tighten them until they are snug -- do not over-tighten!

How To Drain the Fuel Tank and Carburetor of a Honda Mower Engine

2024-10-22T11:53:00-05:00

When a mower sits for a while (even a few weeks), it might be a good idea to drain the fuel out of the gas tank and add fresh fuel before mowing. Because of the higher ethanol content in gasoline as compared to previous years, the gas will begin to go bad even after about a week. Most of the time, this decrease isn't noticed right away, but over an extended period of time the gas will start to change internally and will also begin to produce an odor that is not pleasant (well, not that we suggest you sit there and sniff fresh gasoline all of the time either).

Here's a quick recap of the video:

Draining the Fuel Tank

One method of removing fuel would be to siphon the fuel out of the tank. Another option (probably the easiest) is by removing the fuel line from either the carburetor, fuel pump or fuel shutoff valve and draining the fuel into a pan. Make sure you take that fuel to your local recycling center.

How to Drain a Honda Carburetor

As seen in the video, there is a blue painted screw on the bottom of the carburetor. This allows the fuel to be drained out of the bowl of the carburetor so that fresh fuel can make its way in when you go to start the mower. Carefully loosen this screw and drain the carburetor and then carefully tighten the screw until it is snug. Remember not to over tighten!

Here's a quick recap of the video:

Draining the Fuel Tank

One method of removing fuel would be to siphon the fuel out of the tank. Another option (probably the easiest) is by removing the fuel line from either the carburetor, fuel pump or fuel shutoff valve and draining the fuel into a pan. Make sure you take that fuel to your local recycling center.

How to Drain a Honda Carburetor

As seen in the video, there is a blue painted screw on the bottom of the carburetor. This allows the fuel to be drained out of the bowl of the carburetor so that fresh fuel can make its way in when you go to start the mower. Carefully loosen this screw and drain the carburetor and then carefully tighten the screw until it is snug. Remember not to over tighten!

Troubleshooting a Surging Engine

2024-10-22T11:53:00-05:00

If your engine is surging or running unevenly, chances are that something is wrong. Some engines will seem to surge when there's no load because when the drive, auger (if a snow blower) or blade (if a mower) are disengaged, the governor will keep it from reaching full throttle. If the engine still surges while there's a load on it (or it dies out completely), here are some quick tips to troubleshooting an engine surge:

Carefully inspect your fuel line as your fuel line may be clogged, dry-rotted or broken
Drain your carburetor and fuel tank as you may have water in the fuel
If the machine is equipped with a fuel pump, check to make sure it is working properly.
Inspect your governor as it may be set improperly or sticking in place.
Clean, rebuild or adjust your carburetor. Always start with an adjustment and then move on to larger projects such as cleaning or rebuilding the carburetor.

Carefully inspect your fuel line as your fuel line may be clogged, dry-rotted or broken
Drain your carburetor and fuel tank as you may have water in the fuel
If the machine is equipped with a fuel pump, check to make sure it is working properly.
Inspect your governor as it may be set improperly or sticking in place.
Clean, rebuild or adjust your carburetor. Always start with an adjustment and then move on to larger projects such as cleaning or rebuilding the carburetor.

How to Look Up Small Engine Parts

2024-10-22T11:53:00-05:00

Here's the information you need to look up small engines. Please refer to our Model Identification Guide for more information on where to find these numbers.

Briggs & Stratton: model, type and code
Honda: model and serial
Kawasaki, Kohler or Tecumseh: model and spec

Here's the information you need to look up small engines. Please refer to our Model Identification Guide for more information on where to find these numbers.

Briggs & Stratton: model, type and code
Honda: model and serial
Kawasaki, Kohler or Tecumseh: model and spec

Troubleshooting A Crankcase Breather That Is Blowing Oil

2024-10-22T11:53:00-05:00

If your crankcase breather is passing oil, chances are that something's wrong (Okay, we know something's wrong, but don't be too alarmed). Here are some things to look for while you're searching for the source of the issue:

Too much oil in the crankcase (overfilled!)
Engine speed is too high
Oil filler cap or oil fill gasket is damaged or missing
Breather mechanism is dirty, damaged or defective
Piston ring gaps are aligned
Piston rings are worn
Blown head and pressure is being blown out of the breather

Too much oil in the crankcase (overfilled!)
Engine speed is too high
Oil filler cap or oil fill gasket is damaged or missing
Breather mechanism is dirty, damaged or defective
Piston ring gaps are aligned
Piston rings are worn
Blown head and pressure is being blown out of the breather

Troubleshooting Why Your Engine Lacks or Has No Power Even After It's Warm

2024-10-22T11:53:00-05:00

Here's a list of things to think about (and check) when your engine is lacking the power that it once had. There are a few possible causes to missing power from an engine and here are a few things to ponder:

Your engine may have old gas in the tank. Fuel in the last couple of years now has up to 10% ethanol. This ethanol attracts moisture (water) and debris which reduces fuel quality and may cause the engine to run rough (or not at all). Draining your fuel tank and carburetor is a good place to start.
The spark plug in your engine might be fouled, corroded or damaged. Please visit our website to order spark plugs online.
Check the oil using your engine's dipstick. If your oil is old, dirty or thick, this may cause the engine to run slowly and not be properly lubricated. Not only is this not ideal for your engine run quality, but this may also damage internal engine components.
Adjust the carburetor's choke lever -- it may be closed or partially closed. The choke should only be used when cold-starting an engine and will hinder engine performance if left closed or partially closed.
The engine's carburetor may need to be cleaned, rebuilt or replaced. Depending on the cost of the carburetor, it may be cheaper to purchase a new carburetor than to purchase a rebuild kit and take the time to rebuild it.
The engine's ignition timing may be off. Please see your service manual or local small engine repair shop for troubleshooting.
Check your engine air filter -- it may be dirty enough to clog proper air intake for the engine. Always remember to clean your air filter at regular intervals and replace your air filter when it becomes too dirty.
Many types of outdoor power equipment have suggested lubrication locations on the engine and the unit itself. Please consult your equipment's service manual for grease locations.
Improper sealing of the valves of the engine.
The engine's piston rings may not be sealing correctly.
The cylinder head may be loose or the head gasket might be blown or damaged. Usually this happens when the engine overheats or is run low on oil.
On a two-cycle (2-cycle or 2-stroke) engine, check to make sure that the exhaust ports are not blocked.

Your engine may have old gas in the tank. Fuel in the last couple of years now has up to 10% ethanol. This ethanol attracts moisture (water) and debris which reduces fuel quality and may cause the engine to run rough (or not at all). Draining your fuel tank and carburetor is a good place to start.
The spark plug in your engine might be fouled, corroded or damaged. Please visit our website to order spark plugs online.
Check the oil using your engine's dipstick. If your oil is old, dirty or thick, this may cause the engine to run slowly and not be properly lubricated. Not only is this not ideal for your engine run quality, but this may also damage internal engine components.
Adjust the carburetor's choke lever -- it may be closed or partially closed. The choke should only be used when cold-starting an engine and will hinder engine performance if left closed or partially closed.
The engine's carburetor may need to be cleaned, rebuilt or replaced. Depending on the cost of the carburetor, it may be cheaper to purchase a new carburetor than to purchase a rebuild kit and take the time to rebuild it.
The engine's ignition timing may be off. Please see your service manual or local small engine repair shop for troubleshooting.
Check your engine air filter -- it may be dirty enough to clog proper air intake for the engine. Always remember to clean your air filter at regular intervals and replace your air filter when it becomes too dirty.
Many types of outdoor power equipment have suggested lubrication locations on the engine and the unit itself. Please consult your equipment's service manual for grease locations.
Improper sealing of the valves of the engine.
The engine's piston rings may not be sealing correctly.
The cylinder head may be loose or the head gasket might be blown or damaged. Usually this happens when the engine overheats or is run low on oil.
On a two-cycle (2-cycle or 2-stroke) engine, check to make sure that the exhaust ports are not blocked.

Troubleshooting a Small Engine Knock

2024-10-22T11:53:00-05:00

An engine knock can be a serious problem and can lead to serious internal engine damage if not addressed quickly and accurately. Here are some possible causes to help you troubleshoot an engine knock yourself. Unfortunately, the chances are that the engine knock IS something serious and could result in some serious labor to fix (or it might be better just to replace the engine).

The magneto may not be timed correctly.
The carburetor is set too lean.
The engine has overheated
There is carbon build-up in the combustion chamber of the engine.
The flywheel may be loose.
The connecting rod is either loose or worn (or both).
The cylinder is worn and needs service.

RCPW Hour Meter for Preventative Maintenance

2024-10-22T11:53:00-05:00

How would you feel about getting into a car when you were unsure how much gas was in the tank? Would you drive around with complete confidence or would you constantly be worrying about when you would run out of gas in a most inconvenient way? Or how would you feel about taking a long trip in your vehicle without having a map or GPS to set you on the correct path for your destination. Individuals take the time to plan and map out trips, as well as, they take the time to regularly put gas and oil into their vehicles based on the knowledge gained through the instruments within those vehicles. It is equally important to take the same approach with your lawn mowers.

Preventative maintenance is a proactive way to ensure that your lawn equipment runs at peak capacity for years. It is essential to set up regular preventative steps in order to lead to the trouble-free operation of your mower. Knowing when to service and maintain your lawn equipment is an essential key in this process. Preventative maintenance can be as simple as looking over your lawn mower before and after usage, making sure that gas and oil levels are at appropriate levels, as well as, using simple instruments that give key information regarding usage.

RCPW is happy to introduce an affordable instrument to set you on that road to success. We are now manufacturing and selling the RCPW Hour Meter which keeps track of how long the lawn mower engine has been running. This maintenance tool is essential so owners can see how many hours their equipment has run in order to see when service is needed. With the utilization of the RCPW Hour Meter many benefits can follow including: your lawn mower will be in top working condition, extended life of your mower, and maximization of your investment throughout the life of your mower.

When one takes the time to look at the map and to set up the road marks leading to their destination, success is accomplished. Set yourself up for ultimate success today with this RCPW Hour Meter!

Interested? Click here for more information about the RCPW Maintenance Hour Meter

When one takes the time to look at the map and to set up the road marks leading to their destination, success is accomplished. Set yourself up for ultimate success today with this RCPW Hour Meter!

Interested? Click here for more information about the RCPW Maintenance Hour Meter

What to do when your engine starts knocking

2024-10-22T11:53:00-05:00

Knock Knock, who's there? Oh no! It's your small engine. An engine knock is a sign that some form of engine maintenance is needed before a serious problem arises if it hasn't already. Luckily there are some simple things you can do to troubleshoot your small engine and determine whether or not more serious repairs are going to be needed.

You'll need a few things from around the garage to start your diagnostics, but before you gather those, let's start here: if your engine has been running, power it down and let it cool off. You don't want to possibly burn yourself on a hot engine. Once your mower is turned off, use this time to gather your tools. You'll need an old (but clean!) rag, a drip pan, and a socket set.

Checking the oil level

The first thing you want to check is the oil level. Low engine oil is one of the main causes of engine knocking so you'll want to check this before assuming you need extensive repairs. Once your mower has sat long enough for the engine to cool, you'll want to remove the oil fill cap and dipstick. You're going to take the rag and wipe the dipstick clean, re-insert it and remove it again to get a reading of your oil level. If it reads low, get some motor oil (based on the requirements from your engine owner's manual) and add it until you're at an adequate fill level. Make sure to continually check the oil level as you're adding it, as you do not want to overfill the engine. Keep checking it with the rag and dipstick after adding small amounts of oil. If the knocking sound persists after adding oil or if the oil level was adequate, then you'll want to check a couple other things.

Changing the gas

Another common cause of engine knocking is old gas. Once again, you'll want to make sure your mower engine is cool. While you're waiting for it to cool is a good time to get your drip pan handy. After the engine is cool to the touch, you'll want to place the drip pan near the fuel shut off switch on your engine. One way to drain the old fuel from your engine is to disconnect the fuel line from the fuel cut-off switch and position the fuel line so it drains into your drip pan. After the old gas has been drained from the engine reconnect the fuel line to the fuel shut off switch. If you're not comfortable doing this and would prefer a more straight-forward approach, you'll want to place the drip pan in an area where tilting the machine on its side can drain the old fuel into the pan. Make sure you always tilt your mower with the air filter on the top/high side. Now that your pan is in place we can remove the gas cap, lean our mower on its side, and empty the old gas into our drip pan. When the old gas has been fully removed you can stand your mower back on all four wheels, fill the tank with fresh gas and re-secure the gas cap. If the knocking sound still persists after changing your gas, there are still a few things you can check.

Disconnecting the fuel line from the fuel shut-off switch to drain old gas.

Checking the air filter

The next stop in your diagnostic testing is to check the air filter. To do this, you'll need to remove the wing nut, screw, or clip-on cover that holds the air filter cover in place. This will allow you to remove the top half of the air filter cover. Once the air filter cover has been removed you'll remove the air filter and inspect it. If the filter looks extremely clogged, dirty, or deteriorated it would probably be a good idea to replace it with a new one. You should also check the air filter cover and housing for debris. Be cautious when cleaning the air filter housing because debris can easily enter the engine without a filter. Gently clean the housing with a clean rag. After your filter has been inspected or replaced, insert it into the air filter housing, reattach the air filter cover, and re-secure it. Now that you've inspected the air filter (and possibly replaced it), you'll want to start the mower. If your engine has quit knocking then you solved the problem! If it's still knocking, you'll want to take a look under the mower deck.

Opening the air filter cover to inspect the air filter

Checking the blade / checking under the deck

After your mower has been turned off and it has cooled down, lay the mower on its side with air filter on the high side. This will keep oil from getting into the air filter. Take a look at the blade under the mower deck. Sometimes the knocking sound you hear could be the result of a loose, bent or wobbling blade. If you've recently removed or replaced the blade and it suddenly started knocking, this is quite possibly the cause of your issue. Begin by checking to see if the blade retaining nut is tight. If this is loose, it could cause the blade to wobble so you'll want to tighten it with your socket set. Please note that we do recommend attaching blade nuts with an impact wrench whenever possible. If the nut is tight but the blade looks out of place or looks like it isn't seated correctly, you're going to want to remove the retaining nut with your socket set or impact, pull the blade off, and then re-seat it properly onto the shaft/blade adapter. Once the blade has been properly re-seated, you can tighten the retaining nut to secure the blade in place. If your blade looked excessively dinged up or bent to the point of making contact with other objects under the deck, you'll want to replace that blade as soon as possible. Having a blade that is making contact with other objects in your mower deck is very dangerous and it should be replaced immediately. If your knocking hasn't stopped after inspecting the blade and replacing it, then there is one last thing we can check.

Carefully removing lawn mower blade from under the deck.

Checking the spark plug

Sometimes engine knocking can be caused by the engine not firing in sync. This could be caused by a bad or misfiring spark plug. To test this you'll need a spark plug wrench to remove the old spark plug. Take it with you to our local lawn mower service/repair shop to get your replacement spark plug. When replacing the spark plug, always remember to hand-thread the plug into the cylinder to make sure you don't strip the threads. After hand-turning, tighten with your spark plug wrench and start up the mower. If the engine stopped knocking, you've solved your problem. If you're still hearing the same engine knocking sound then you need to take your mower to a certified mechanic or lawn mower service center and have them look it over. It could be a much more serious issue and the more often your mower is ran with this issue, the more damage you could be doing to it.

Removing spark plug with spark plug wrench.

Hopefully one of these steps has solved your engine troubles. Engine knocking can be the sign of a serious issue with your small engine and if these steps didn't solve your problem, your mower needs to be looked at by a certified mechanic. The mechanic will be able to provide you with an estimate of repair costs and can inform you about the extent of the damage as well as if it may be easier (more cost efficient) to simply replace the entire engine on your mower.

Checking the oil level

Changing the gas

Disconnecting the fuel line from the fuel shut-off switch to drain old gas.

Checking the air filter

Opening the air filter cover to inspect the air filter

Checking the blade / checking under the deck

Carefully removing lawn mower blade from under the deck.

Checking the spark plug

Removing spark plug with spark plug wrench.

How To Troubleshoot Your Small Engine

2024-10-22T11:53:00-05:00

Every repair project should begin with a troubleshooting phase. This is the phase of your repair project where you'll identify the source of a problem, starting with the most obvious solutions and working towards complex solutions for less obvious problems.

The best way to thoroughly troubleshoot your engine is to systematically work through the various parts and systems in the engine to rule out possible causes of your issue. Being thorough is very important when troubleshooting your engine. Trying to identify what's wrong with your engine can be likened to trying to find a lost remote control. Many times it's located in a very obvious spot that didn't seem logical enough or too simple to check. The answer to this is to be very thorough and not overlook things that may seem too obvious. Your remote just may be sitting there in the open.

The most important thing to remember when troubleshooting your small engine is to avoid the "bandage on a broken leg syndromeGÇ¥. Simple solutions aren't always the correct solutions they may only be a partial solution. For example: replacing a worn spark plug may get an engine to start, but the real issue may be a carburetor that is partially blocked. In this instance this problem will most likely arise again.

For Successful Troubleshooting

Consider all symptoms carefully
Look for the cause, not just a cure (avoid the "bandage on a broken leg" syndrome)
Gather as much information as possible. Knowing specifics of how the engine stopped working or if it just won't start can make a difference in identifying the problem.

Common four-stroke small engine problems

Engine Won't Start

Fuel Line Problems
Carburetor Problems
Ignition Problems
Compression Problems

Engine Runs Poorly

Engine Smokes
Engine Overheats
Engine Knocks
Engine Misses Under Load

Common two-stroke small engine problems

Spark Plug - Bad or No Spark
Fuel Related Problems
Compression Problems

It's important to know exactly what you're trying to fix when repairing your small engine. Doing some basic troubleshooting can help you narrow down and isolate the cause of your small engine problem. Knowing the cause of the problem is half the battle. Once the problem has been located you can take the next steps to repair or replace the damaged or non-functioning parts in your small engine and get your outdoor power equipment running again.

For Successful Troubleshooting

Consider all symptoms carefully
Look for the cause, not just a cure (avoid the "bandage on a broken leg" syndrome)
Gather as much information as possible. Knowing specifics of how the engine stopped working or if it just won't start can make a difference in identifying the problem.

Common four-stroke small engine problems

Engine Won't Start

Fuel Line Problems
Carburetor Problems
Ignition Problems
Compression Problems

Engine Runs Poorly

Engine Smokes
Engine Overheats
Engine Knocks
Engine Misses Under Load

Common two-stroke small engine problems

Spark Plug - Bad or No Spark
Fuel Related Problems
Compression Problems