Servicing your John Deere mower.

john deere riding mower

Follow these tips for faster and better lawn tractor maintenance. Good maintenance will prevent expensive repairs in the future.

You’ll save too. Dealers typically charge more than $200 for routine maintenance that includes an oil change and new spark plugs and filters. But you can do all these things—and more—in just a few hours.

  1. Get everything you need to do the service together
  • Spark plugs
  • Air filter
  • Oil filter
  • Oil

A great way to start is buying a Kit with everything you need. This can save you money and make sure you have the right parts for the job.

Here is a great spot to get those parts and save money at the same time. John Deere Service kits.
John deere service kits

Change spark plugs

Spark plugs are the 1 of the most important but least expensive components in the engine. Change them regularly for easy starting and fuel economy.

Worn spark plugs cause a variety of problems, from hard starting and poor fuel economy to hard starts and even damage your engine. So replace them at the recommended intervals. Changing plugs is a simple matter of removing the old ones and installing in new ones. But these are a few of the things to keep in mind:

Keep it clean. Prevent debris from falling into the cylinder by brushing or blowing around the plug before you remove it. After removing the plug, wipe out the spark plug seat with a clean rag.
If an old plug won’t turn, use a spray lubricant that will penetrate into the threads.
Set the gap of the new plugs before installing them. Check the manual for gap specifications and use a gap gauge.
Don’t over tighten the plugs. If you don’t have a torque wrench, follow this general rule: First, finger-tighten the plug. If the plug has a compression gasket, tighten it an additional half turn using a plug wrench.

Fuel filter.

Replace the fuel filter without spilling gas Pinch off the fuel line with a vicegrips to stop any gas flow. As you remove the old filter, plug the openings with your fingers.

An old filter can cause hard starting, poor fuel economy, even an expensive carburetor rebuild. I recommend you change your fuel filter every Year.

Replacing the fuel filter is easy. First, pinch the fuel line leading from the tank with a clamp. Then move the spring clamps away from the filter with pliers. Remove the inlet hose. Drain the small amount of fuel from the fuel line into a drain pan. Then, plug the filter inlet with your thumb, tilt the entire filter down, and pull it out of the outlet hose. Place the old fuel filter in the drain pan and install the new filter. Pay attention to the fuel flow direction arrows—the arrow shows the direction the fuel is traveling to the engine. Move the fuel line clamps back into place.

Replace the oil filter

Just like your car, mower needs regular oil changes. Pay attention to the recommended viscosity (such as 10W- 30). Never, ever change the oil without also changing the oil filter. To prevent a buildup of gunk on the engine, wipe up any spilled oil. Bottle the old oil and take it to your nearest oil recycling center for disposal.
Screw on the new oil filter until the rubber gasket touches the seat. Then give the filter another half turn. Spread a light coat of oil on the gasket so it doesn’t bind against the seat.

Clean the filters

Wash the foam prefilter and blow off the filter at least once a month during the mowing season.

It is  a good idea to clean the filter between changes. If your tractor has a foam prefilter, wash it with soap and water; never use a solvent or other cleaner. Blow out the paper filter with a light blast from an air compressor. Keep in mind that this is not a substitute for regular filter changes. I recommend you replace it with a new one every year.

Get everything you need to do the service together

  • Spark plugs
  • Air filter
  • Oil filter
  • Oil

How many small engines do you have?


These engines help us live a simple and easier life. They do jobs for us that make our life easier and save us lots of energy, which is very important to people of all ages.

These tools make it possible to continue to live the lifestyle we have chosen. They do everything from pump water, blow snow, generate electricity, till the garden, cut brush, cut firewood, and propel a small boat.

All these engines must run, and do the jobs they were designed to do. For those of you who also have small engines and rely on them, this article is written to help you keep them maintained and to help you diagnose a problem if it does occur. There’s nothing more frustrating to us than to be out fishing and the engine won’t start or going to the woodlot only to find the chainsaw starts, but runs roughly or sputters and dies. Instead of getting your chores done, you end up driving into town to your local repair shop.

Today’s small engines are rugged little critters, and I’ve found that because of that fact, most people neglect them. Where they change the oil religiously in their automobile, they don’t on their lawnmower. They take their car in for a tuneup, but don’t remember the tiller. This neglect is the main reason their engines fail, or do not run for their rated life expectancy. Recently a friend brought me her tiller and asked me to look it over to see if it could be repaired. My diagnosis? Why did it fail? It failed because the air cleaner had never been changed. Why is this important? A small gas engine can literally ground its innards to death because of dirt that got into the combustion chamber. On top of that, the oil in the crankcase needs tl be changed. Just topped off when it was low. The oil lost its ability to lubricate, and was full of grit particles and dirt. That’s death to engines.

Two types of engines

So it is time for you to learn a camshaft from a crankshaft, and how to maintain your engines. It is not beyond your comprehension.

There are two types of Small engines. Two stroke or four stroke. At this point, the only reason this is important to you is the lubrication methods are different. The two stroke requires you mix the oil with the gas. The four stroke is like your auto engine. There is a separate compartment for the oil and a separate fuel tank.

To identify them, two stroke engines are generally used on chainsaws, weedeaters, and other tools that are used at many angles. Chainsaws are a great example of this. Think about all the various angles in which a chain saw is required to run when cutting down a tree. Upside down or 90 degree angles aren’t uncommon. So having the oil mixed with the gas keeps the engine lubricated no matter how it’s tilted or angled.

Four stroke engines are usually found on tools such as lawnmowers which stay horizontal most of the time they are in service. Thus the oil stays in the bottom of the crankcase where oilers or
other mechanical parts distribute the oil to the areas of the engine that require it. Another easy way to know is, generally, two stroke engines are on tools you must lift and carry, i.e., chainsaws and weedeaters. They have many fewer parts than a four stroke engine so they are lighter. Four stroke engines are on tillers and most lawnmowers but not all.

The oil is not only a lubricator, it also helps with heat transfer. Small engines run very hot and are generally air cooled, so it’s imperative the oil is mixed in the proper proportions in the gasoline (two stroke engines), or kept clean and up to the required level in the crankcase.

Here is a great place to buy Service kits for your annual service. Annual Service kits.
Engine cooling vital

Inadequate cooling is the second most prevalent reason for small gas engine failure.

First, keep the engine clean. It’s a simple procedure. After using the engine in the garden or mowing the lawn, let it idle under no load for a few minutes to let it cool down for a while before you turn it off. This is very important. These small gas engines run very hot, especially if they’ve just tilled heavy soil or cut high grass. Letting them cool down to normal operating temperatures before turning them off will allow the metals to cool down slowly. It will add many hours to the life expectancy of your engine.

Also it is a good idea to shut the fuel off an the shutoff valve and let the engine run until it is out of gas. This will empty the carburetor. This helps to keep it clean and have less repairs.

After turning it off, let it cool and then clean all the dirt, twigs, and grass off the cooling fins and the engine block. These engines “cool themselves” by radiating heat into the surrounding air. If they’re covered with matted grass clippings, dirt and oil, it is hard for them to cool.

Second, never remove the engine shrouds. Except to work on the engine and then always replace them. They are designed to channel air around your engine to help it cool.

Think of the system on your small engine like the air conditioning ducts or heat ducts from your furnace or air conditioning system. The ducts provide passageways to move hot or cold air where it’s needed. The engine has the same kind of system. The flywheel acts as a fan and forces air into the shrouded area around the engine, thus carrying off the heat as the cooler air races by. By removing the shroud or not repairing dents to it, you are defeating the cooling system.

Fuel mix

Now let’s get to fuel and fuel mix. As we learned earlier, the two stroke requires you mix oil with the gas. This really can be confusing, especially if you have three or four engines that require different ratios in the mix. You will find the ratio mix in your manual that came with the engine, or many times it’s printed right on the gas/oil tank cap.

There are two firm rules on this. Use only two stroke engine oil in two stroke engines. Do not use car engine oil like SAE 10W-30W, or the like. Two stroke engines burn oil and are designed to do this, and require the proper oil in the gasoline. Mix the gasoline and oil thoroughly, and I mean thoroughly. One great method is to take your gas and oil can to the gas station and make the mix right there at the pump. Fill the gas can about 1/3 full and then add the proper amount of oil, then fill the container. The gasoline pumping quite rapidly out of the nozzle mixes the oil and gas together quite well. Later when you go to fill your tiller or generator, shake the gas can vigorously before filling the tank.

There are also High Performance Semi-Synthetic 2-Cycle Oil has been specifically developed to give a long trouble-free life to gasoline-powered 2-cycle engines and is designed for any oil injection system or pre-mix up to 50:1. The oil uses an advanced “smokeless” formula specially blended from mineral oil, synthetic oil and a low-ash additive package containing fortified dispersant inhibitors. Lucas ashless detergent inhibitor package minimizes spark plug fouling, pre-ignition, ring sticking and combustion chamber deposits. The user can expect cleaner exhaust ports and spark plugs, less carbon buildup on the piston rings, skirts, crown and under crown areas. It also contains exclusive detergents and lubricants. The end result of this advanced technology is a more thorough burning of the fuel, resulting in more power and fewer emissions.

Where to find Simi-Snthetic 2-Cycle oil. Two Cycle oil!

The oil must be in very small particles and suspended evenly in the mix, so the engine gets lubricated evenly. If the oil is not mixed thoroughly, the engine starves for lubrication, and the spark plug gets big “globs” of oil stuck on it so it can’t fire. You’ll spend wasted time taking out the plug, cleaning and drying it to keep your engine running.

Gasoline is also important. Head for your manual for types of gasoline and octane rating your engine requires. Some older engines require leaded gasoline. Most of the newer engines run on leaded or unleaded.

Once gasoline is on hand, use it. Don’t buy 10 gallons of gasoline and use five gallons per year to mow your lawn for two years. Gasoline allowed to sit gets stale, gummy and in the case of ethanol or unleaded gas attract water. This buildup sticks especially to carburetor parts and air passages which eventually will restrict air flow, thus changing the air-gasoline mixture that’s required for good engine operation. This simple precaution will save you a lot of downtime and lots of money. A replacement carburetor or a carburetor rebuild will cost you $25 to $250. Using gasoline within 30 days, as you can see, is very cost effective.

Benefits of simple care

This basic information on small engines. If followed, could will save you lots of downtime and lots of expense. On one hand, I appreciate people who don’t maintain their equipment, as it is a means of income to me. But on the other hand, I hate waste. As an ad for oil filters says on TV: “You can pay me now, or you can pay me later.” You can do simple maintenance like cooling slowly, changing oil, proper fuel mixing, changing air filters, all for little or no cost.

Why pay me, or another technician, lots of money for a valve job, carburetor rebuild, or engine overhaul that’s needed because of neglect? Today’s small engines are rated for approximately 1000 hours of life expectancy before complete rebuilding or replacement is necessary. That doesn’t sound like a lot, does it? But figure how you use your lawnmower. Two hours a week for a six-month season would be about average, or 48 hours a year. At this rate your engine could last 20 years.

Simple home maintenance coupled with a couple of trips to a small engine technician for tune-ups and inspection over that 20-year life can save you lots of money and your engine will roar to life and do its job consistently.

Need tools for those repairs? Here is a great stop to find tools!

If you have no manual for your engine, either go to a small engine sales shop and request one or write the engine manufacturer directly. If you have an old engine, when writing the manufacturer, tell them the information that’s on the engine specification plate. If you can find no plate, tell the manufacturer what machinery the engine powers and the approximate age. This will help them get an appropriate manual to you.


Replacing you Honda Mower , Briggs and Stratton or other small engine Carburetor.

There are many different carburetor setups for small engines. But when it comes to removing the steps are usually the same.

  1. Remove the Fuel line from the Carburetor.
  2. Remove the Air filter and its housing.
  3. Remove the Carburetor mounting bolts.
  4. Remove the Linkage.

First make sure the fuel is shut off. Shut off valves can be located in many places. Under the tank

small gas engine fuel tank

In the Line.

Or built in to the Carburetor.

small gas Carburator fuel shutoff solinoid

If your only shutoff is in the carburetor of your lawn mower or other small gas engine.

I suggest getting one if the inline Shutoff valves. Also if you are removing the Carburetor you will need to crimp the Line if this is the only Shutoff.

  1. Remove the air filter. When removing the air filter is important that you use care not to drop anything down the Carburetor. I find if you stuff a clean shop cloth in the Throat of the carburetor is a good solution.
  2. Remove the air filter housing.
  3. Find and remove the Carburetor mounting bolts.
  4. Remove linkage.


Here is a great video to replacing your Briggs and Stratton Carburetor.

The problem with fuel lines on small gas engines these days is Unleaded Gas. Unleaded gas and ethanol “or alcohol” break down rubber and rubber compounds.

Small engines on your lawnmower, ATV or motorcycle use a gas-resistant vinyl tubing called Tygon. It is usually clear or transparent yellow in color and is preferred over the clear vinyl tubing you can purchase for your beer keg tap or for use as a wiring loom.

Tygon is available in short sections or on a large roll and can be quite expensive.  However it will outlast the standard vinyl by many years and does not turn brown and brittle after extended use as vinyl tubing often does.

I suggest you replace those old fuel lines on your small gas engine with new ones that do not react to the ethanol. I have found that pure tygon fuel line works the best.


Here is a good video on ethanol based gas and how it affects you small gas engine.

Now Lets take a look at spark plugs in small gas engines.

To test spark first remove the spark Plug.

The first thing you should check is the condition of the Plug. Is there lots of buildup on the plug? Is the glass (white part of the plug) cracked or broken?

If the plug looks ok then you can either use a tester made for checking for spark or with the plug removed hold the base of the plug against the engine and turn the engine over.

Be careful, the spark from a Honda small engine or other small engine is a high voltage discharge. If there is no spark first check to make sure the unit is turned on and that all safety switches are working.


If there still is no spark I usually check electronic ignition. Most of the newer Briggs & Stratton, Honda and other small engines use an electronic ignition system. See section on electronic ignition system. Ok so now you should have spark.

Here is a good video I found on checking the spark on your small gas engine.

So again step by step to check your small gas engine spark plug:

  1. Remove The Plug
  2. Check Condition Of the Spark Plug
  3. Test Spark Plug
  4. Double Check Safety Switches


Valves control the flow of fuel vapor into the combustion chamber and the flow of exhaust gases leaving the engine. Faulty or dirty valves may stick and can develop pits, cracks or grooves that cause the engine to lose power and fuel efficiency.

Whether you’re having trouble with your engine or wanting to go through your routine valve maintenance, make sure you have our step-by-step guide on how to check your engine valves. From removing the valve, to cleaning for inspection, find information for valve maintenance for your Briggs & Stratton engines.

How to Adjust Overhead Valves

  • Step 1: Release the brake spring. Then, turn the flywheel to close both valves.
  • Step 2: Insert a narrow screwdriver into the spark plug hole and touch the piston. Turn the flywheel clockwise past top dead center until the piston has moved down 1/4″. Use the screwdriver to gauge the piston’s range of motion.
    valve adjustment small gas engine 1
  • Step 3: Check the valve clearance by placing a feeler gauge between the valve head and the rocker arm. Clearances differ for the two valves and typically range from .002 – .004″ to .005 – .007″.
  • valve adjustment small gas engine 2
  • Step 4: Adjust the clearances as required by turning the rocker screw. Once adjustments are completed, tighten the rocker nut.
  • Step 5: Install the valve cover, using new gaskets, as required, and make sure the cover is secure.

Here is a good video I found for adjusting the Valves on your Predator Small Gas engine.

So what is good compression on a small gas engine?

Most Briggs & Stratton, Honda or other small engine, 2 or 4 stroke must have at least 90lb of compression to run.

  1. Start by removing the spark plug. When you turn the engine over with the spark plug out there should be air blowing out of the spark plug hole on the compression stroke.
  2. Place your finger over the spark plug hole and on the compression stroke it should force your finger away from the hole.
  3. But I suggest using a compression tester.

Here is a good video on doing a small gas engine compression test.

What to do if your small gas engine compression is low?

If you do not have good compression also see my post on Valve adjustment.