Why do my lawnmower wheels wobble?

As lawnmowers get used, eventually the hard plastic housing on the wheel hub will wear against the axle bolt and start to “wobble”. A quick fix for this is to install a bushing into the wheel. This is done by removing the “wobbly” wheel form the mower and drilling out the axle bolt hole in the wheel from a wobbly 1/2″ to a new 5/8″ ID (inside diameter) hole. Then purchase a nylon bushing with a 1/2″ ID and a 5/8″ inches OD (outside diameter) and tap this bushing into your newly enlarged axle hole.

The nylon material of the new bushing will give the wheel new strength and longer life.

How do I check if I have spark?

Hi all of you DIY’ers!

Here is a link to a great video from Don The Small Engine Doctor who clearly shows how to safely check for spark on a small engine. In the diagnosis of a small engine “no start” issue there can ONLY be 3 thinks that can go wrong to prevent the engine from starting:

  1. Electrical – No Spark
  2. Fuel – No fuel flow to create a combustible fuel air mix
  3. Mechanical – No compression in the cylinder – no power to drive the piston down.

Of course you can have more than one of these issues at a time to cause a “no start” condition but if you work through each one you will find what the issues are. By far a “no spark” / “no fuel” condition is the most common issue with a small engine “no start” condition.

How to check for spark on a small engine.


Laser Larry!




What is tire ply? Should I use “2 ply” tires or “4 ply” tires? What’s the difference?

Ply rating, in regard to small power product tires, is the number of nylon, polyester or even steel cord layers that are embedded under the rubber tread of a tire. You can’t see these various ply layers but they are important to ensure that the tire can handle its published rating. The number and type of ply plays a major role in the performance and load carrying capacity of a tire. There are differences between tires with different number of ply. A 4 Ply tire is more resistant to punctures, can take more load, and take tire repair better than a 2 ply. A 2 ply tire is usually less expensive than a 4 ply, can’t take as much load as a higher ply tire and tends to flex more when hot.

When shopping for replacement tires for your small power product it is always best to acquire the exact tire that is recommended by the manufacturer. It is not advisable to replace a tire with a lesser ply tire.

How Do I Tune Up My Lawnmower?

Special thanks to Jeff Gorton on the following:

“Keep your mower running like new.”

Mowing is enough of a chore without having to deal with a rough-running, poor-cutting lawn mower. With just a few bucks’ worth of parts and a couple of hours’ work, you can get your lawn mower in prime shape to start the mowing season. We’ll show you how to drain the old gas, replace the air filter, put in a new spark plug, change the oil and sharpen the blade—tasks that will keep your gas-powered mower starting easy, running smooth and cutting clean.

1. Add fresh gas at the start of the season:

Fuel system problems top the list of lawn mower malfunctions. Many of these, like gunked-up carburetors, are often caused by gasoline that’s been left in the mower too long. Although fall is the best time to take preventive measures, you can at least get off to a good start in the spring by replacing the old gas in your tank with fresh gas. Gasoline is highly flammable. Work outdoors or in a well-ventilated area away from sparks and flame. Wipe up spills immediately and store gas in approved sealed containers. To dispose of the old gas, call your local hazardous waste disposal site for instructions. Most mowers have a mesh screen over the outlet at the bottom of the tank. If you can see the screen through the filler hole, use an old turkey baster to suck up dirt and debris that may be covering it.


2.Change your oil regularly:

Changing the oil in your lawn mower takes about 15 minutes and costs less than $5. That’s time and money well spent considering that changing oil at the recommended intervals will greatly extend the life of the engine. Most engine manufacturers recommend an oil change at least every 25 hours of operation or every three months. Older mowers have a fill plug close to the mower deck. Fill this type until oil reaches the threads of the refill hole. Two-cycle engines that use a gas/oil mix for fuel don’t have an oil reservoir on the engine and don’t require oil changes.

Before you drain the old oil, run the mower a few minutes to warm the oil and stir up sediment. Then disconnect the spark plug, drain the old oil and add new. Use SAE – W30 oil (check your owner’s manual). There are two ways to drain old oil: through the filler neck or out the drain plug in the bottom of the engine. It’s quicker and easier to drain the oil through the filler neck if your mower has one. If you have an older mower without a filler neck, locate the drain plug on the bottom of the engine and remove it to drain the oil. Pour used oil through a funnel into a plastic milk jug or other container and label it for recycling.

Whenever you tip a lawn mower up on two wheels to work on the underside, only lift the side with the air cleaner. This prevents oil from running into the carburetor and soaking the air filter. Also, if your lawn mower has a fuel valve, turn it off.

Remember to check the oil level occasionally between oil changes, setting the mower on a level surface. Top it off as needed. Newer mowers have dipsticks with markings that indicate when to add oil. Don’t overfill. Check your manual for instructions to see whether the dipstick should be fully screwed in or just set in when you’re checking the level. If you accidentally add too much oil, follow the procedure to drain some out.


CAUTION: Always disconnect the spark plug wire from the spark plug before reaching under your mower.

3.Add pep with a new spark plug:

Often a new spark plug will make a big improvement in the way your engine starts and runs. Spark plugs are so cheap and easy to install that it’s good insurance just to replace your plug every spring. Check your owner’s manual for the correct spark plug, or take the old plug with you to the store to match it up.

New spark plugs are factory set with a .030-in. gap between the electrodes at the tip of the plug. Inspect the plug when you buy it to make sure there’s a gap about the thickness of a matchbook cover. If there’s no gap, the plug may have been dropped and damaged. Choose another one.

If you don’t own a socket wrench set with a 3/4-in. or 13/16-in. deep socket for changing the spark plug, pick up an inexpensive like the one in the photo above.

4.Don’t suffocate your mower—change the air filter:

Air filters are cheap and easy to replace. Dirty air filters choke the engine, causing it to run poorly and lose power. If your lawn is dry and dusty, check the filter after every few mowings. Otherwise, check it a couple of times during the season. Replace it when it starts to get plugged with dirt and debris. One common test is to shine a flashlight through the filter. If you can’t see the light through the filter, replace it with a new one.

Most newer mowers have pleated paper filters that are either flat or cylindrical, while many older mowers have foam filters. Both types of replacement filters are readily available for $3 to $6 at lawn mower retailers, hardware stores and home centers. Take your old filter along and have your mower manufacturer’s name and model number handy.

In a pinch, you can wash foam filters in a solution of laundry detergent and water and allow them to air dry. But since replacements only cost about $3 – $5, it’s best to just buy a new one. In either case, saturate the foam filter in motor oil and squeeze out the excess before installing it as shown below.

As well, until you get a new cartridge filter (see below) you can clean out a dirty cartridge filter with compressed air. Just be sure blow the compressed air from the inside of the filter to the outside.

5.How to sharpen the blade:

Shut off the fuel feed tap and tilt the lawn mower on its side with the carburetor being on top. This will help prevent your engine from flooding.

Disconnect the spark plug and ground the lead to the engine. Using a piece of 2 x 4 and a clamp (as shown) block the blade so that it can not turn and remove the blade be turning the retaining bolt in a counter clockwise fashion. Note which side of the blade is facing out so that you can put the blade back on the same way.

Use a wire brush to clean off any hard build up of grass from the blade as this can affect the balance of the blade. Inspect the blade closely for any cracks or physical damage. If the blade looks cracked, bent or damaged (see below) – replace it.


With the blade now off of the mower, sharpen the cutting edge to a 30 – degree bevel with a bench grinder. Be sure to wear eye protection and to use light even strokes. Don’t force the blade hard against the grinding stone as that will only cause excessive heat which will lessen the tempered strength of the blade. Dipping the just blade ends in water is a good idea to keep things cool.

To keep the blade in balance be sure to grind off the same amount of material from each end of the blade. If you grind one end of the blade 10 times be sure to grind the other end ten times. Once you have both ends ground sharp and clear of any large indents in the blade edge (greater than 4mm) you can use a bastard file to remove any burred edges from the blade newly sharpened edges.

Place your sharpened blade on a Balancing Cone. If the blade does not sit level on the Balancing Cone – it is out of balance. More material needs to be ground of the blade that is sitting the lowest. Continue to take material off until the blade sits level.

Reinstall the blade and torque the retaining nut to manufactures specifications.

How do I sharpen my lawn mower blade? Getting prepared – Part 1 of 3.

Keeping your lawn mower blade sharp is important to both your lawn mower and your lawn. Those of you who sharpen your own lawn mower blade have 2 options – sharpen the blade while it is on the mower or remove the blade and sharpen it off the mower. In this blog post, I will go through the detailed steps needed to prepare to sharpen your mower blade – either “on” or “off” your lawn mower.

Albeit much faster to sharpen the blade on the mower, removing the blade allows you to do a much better job at sharpening the blade and making sure it is balanced. Regardless of which way you wish to sharpen your blade, there are a few things you need to pay close attention to before you start.

First – safety. Make sure the mower engine start control is set in the “off” position and the spark plug wire is taken off of the spark plug and grounded to the engine. Failing to do this might allow the engine to try and start while you are trying to sharpen the blade or while you are trying to remove it from your lawn mower. This can result in possible bodily injury and damage to your lawn mower. A simple tool called a “Piston Locking Screw” *requires that you remove the engine spark plug so that this tool can be installed. There is now no way your engine can start while you are working on it. Also, this tool prevents your engine crankshaft from turning which makes it much easier for you to remove the blade or sharpen the blade while on the mower.


Using this tool, there will be no no chance of the engine possibly starting, you can now safely work on your lawn mower. If you have a fuel shut-off valve, turn it so that the fuel flow is off and tip your mower on its side with the carburetor side being up. This will help prevent fuel leaking into your engine and flooding it.

Next, and very important, take a close visual inspection of the blade, blade mount, and all blade retaining bolts. Is anything loose, broken or damaged? Is one side of the mower blade bent differently from the other side? Are there large deep “dings” in the blade edges (more than 4mm)? If you find any of the above issues, then you should take your lawn mower to be serviced by a trained technician. If not, then you are now ready to sharpen your lawn mower blade.

Stay tuned for my next 2 blog posts where I go into detail on how to sharpen your lawn mower blade “on” or “off” your lawn mower!

Work safe!

*  For engines where the spark plug is located directly above the engine piston.

Installing 10 mm Spark Plugs – be careful!

How tight you install any spark plug into an engine head is critical. Small engine spark plugs come in different sizes with the most common being 14 mm, 12 mm, and now even 10 mm.

Many newer lawn and garden engines now take the tiny 10 mm spark plugs. The body wall thickness of these spark plugs are deceptively narrow. Once installed these spark plugs have to come back out eventually and over tightening them can cause them to snap off at the threads because a spark plug, like any bolt, requires more torque to remove than to install.

Plug manufacturers have preached for years about using a torque wrench when installing these 10 mm plugs and for good reason. Removing a broken over tightened spark plug can be a big expense. You shouldn’t rely on just the “feel” of tightness – either use a torque wrench or a “seated rotation” guideline to ensure the proper tightness of any small engine spark plug that you install.


Why Won’t My Snow Blower / Lawnmower Idle At One Speed?

If your lawn mower or snow blower refuses to have a smooth constant idle speed and tends to repeatedly speed up then slow down – you have what is known as a “ Hunting and Surging” idle. This is a common occurrence with snow blowers and lawnmowers. With snow blowers this is usually because they sit all summer long stored in some hot garden shed with old gas still in their carburetor and fuel tanks. With time, the gasoline fuel will start to break down leaving a residue that can plug the small fuel circuits in a carburetor. With lawn mowers the “ Hunting and Surging” idle is usually caused by dirt getting into the carburetor as these engines operate in a much dustier environment. However, you can have the same issue if your lawn mower has bee sitting all winter with unconditioned gasoline in its tank and carburetor too!

There are 2 main fuel circuits in a small engine carburetor – the Low speed fuel circuit and the High speed fuel circuit. When one of these fuel circuits becomes partially plugged the engine no longer receives a constant fuel flow. The fuel flow becomes variable which results in the engine idle speed ” Hunting and Surging”. The only thing to do is “get the dirt out” – and that means you will need to clean the carburetor!

When cleaning a carburetor I always try to use something like “Mechanic In A Bottle” first. Just add a cap full to a tank of fuel and let the engine run for 10 minutes. If the residue isn’t too bad you will actually hear the idle smooth out and the “Hunting and Surging” will stop.


If this this does not work then you will need to remove the carburetor from the engine, disassemble it and then allow it to fully soak in “Carburetor Cleaner” for a night. The next day you will need to replace the internal carburetor parts with new parts from an appropriate Carburetor Rebuild Kit.



Okay, now that you have done all this work and finally got your carburetor clean and engine running with a smooth idle – you can prevent this issue from happening again next season by using a FUEL STABLIZER additive. Simply add the recommended amount to your gasoline and your small engine should start first pull next season!

Hope this helps !

Larry Laser

Do I need to “break in” my lawnmower Electric Clutch?


Electric Clutch


Yes, you should “break in” an electric clutch!

A new clutch on your riding mower should be run through a break in process or what is commonly called BURNISHING. This process helps to prepare the clutch surfaces and hence will help to extend the life of the electric clutch. It’s quite a simple process and will only take a few minutes to perform.

  1. Start your mower with clutch disengaged, increase throttle to about 50%
  2. Engage clutch for 10 seconds then disengage clutch
  3. Repeat this five times
  4. Now increase throttle to approximately 75%
  5. Engage and disengage your clutch for an additional 5 times
  6. Check the blade and clutch bolt torque and you are ready to start cutting

Electric clutches aren’t cheap so it is well worth the few minutes of effort to help extend the life of your new electric clutch.

What is the difference between an ” A ” belt and a ” V ” belt?

An “A” style belt are typically industrial belts that are measured for size on the inside of the belt whereas “L” style belts are measured on the outside.

The size difference between an ” A ” belt and a ” L ” belt is always 2 inches.

Therefore, if you have an “A-40″ belt and you wish to replace it with a ” L ” belt you will need a “4L420″ to replace it.

Similarily “B” style belts are measured for size on the inside of the belt as well  – however there is difference of 3 inches to a ” L ” belt

So, if you have a B-56 belt that you want to replace with a ” L ” belt you will need a 5L590 belt to fit properly.

Kevlar V belts are traditionally used with outdoor power equipment, these are coded  as 4L,5L The Kevlar is critical when drives need reverse bending such as on idlers.