Small Engine Smarts: The Five Basic Systems, Part 2

Image by David Reber's Hammer Photography

Previously, we took a look at the fuel system and the compression system. Now let's go over the three remaining of the five basic systems:

System 3: Ignition

System 4: Lubrication and Cooling

System 5: Governor (Speed Control)

Ignition

The ignition system is how your small engine starts. It can be a manual start, meaning you have to pull on a rewind or starter rope in order to turn the engine over the first time and start it running. Or it can be an electric start, which means that it has been equipped with an electric starter motor and a key, and all you have to do is turn that key to crank the engine up. Machines with electric start engines will generally have a higher price point than those without. 

The initial tug on the starting system, whether provided manually or electrically, causes the flywheel to turn. The flywheel has magnets mounted on it, and as the flywheel spins past the ignition armature, an electrical flow will occur and produce a spark at the tip of the spark plug. The spark, which is timed with the motion of the piston and the valves (part of the compression system, remember?), will then ignite the air-fuel mixture in the combustion chamber. Once you give the engine that initial spark, its own momentum will keep it spinning and running.

Common Parts of the Ignition System

• Spark plug
• Spark plug wire
• Ignition armature
• Flywheel
• Flywheel magnets

Lubrication and Cooling

You've certainly noticed that your engine gets hot when it runs. Though some of that heat escapes through the exhaust gases and radiant heat, much of the heat remains in the engine. And overheated engine is an engine that won't keep running long, and that's why lubrication and cooling are so important. 

Oil is the lubricant which keeps engines cooler by reducing friction between the various engine parts. Friction is a major source of heat, so the less friction produced while an engine is running, the less heat. (Note: this does not mean that you should dump in more oil than recommended for your small engine! Excess oil does not mean less friction. Follow the guidelines in your owner's manual.) 

Air is the other cooling component in an engine; you'll notice, on the outside of the engine block, ridged cooling fins which increase the surface area of the engine so that more engine is exposed to more cool air. Keeping the cooling fins clean is an important part of maintaining your engine. 

Common Parts of the Lubrication and Cooling System:

• Oil reservoir
• Dipstick
• Oil dipper or paddle
• Oil filter
• Bypass valve
• Cooling fins
• Flywheel fins
• Blower housing
• Air guides

Governor (Speed Control)

The governor system allows you to use your power equipment under different loads while keeping the engine running at the same optimal speed. For a mower, the load would be how high and thick the grass to be cut is. The higher and thicker the grass, the more of a load the engine is under to move the machine and spin the blades through it. The governor automatically notes changes in the load as your machine encounters them, and adjusts the throttle so that the engine runs optimally without you have to make manual adjustments while you work. 

Common Parts of the Governor System:

• Engine speed control
• Throttle lever
• Governor spring
• Speed control cable
• Throttle linkage
• Governor lever
• Governor cup
• Governor shaft
• Flyweights
• Camshaft
• Timing gear

Arco Lawn Equipment provides how-to articles, advice, and all information on this website for informational purposes only, and cannot be held liable for damage to self or equipment incurred. Please read your owner's manual, follow all safety instructions, wear proper safety apparel, and never allow children or pets to play in or around lawn equipment. Consult a professional small engine technician if you are unsure about any of the steps involved in power equipment maintenance, use, or repair.  

Small Engine Smarts: Regular Maintenance Schedule

By James Lee

One truth that every small engine technician knows - and many homeowners don't realize - is that the regular, scheduled maintenance of your machine can eliminate costly breakdowns down the road. Of course, our human nature and tendency to procrastinate often leave us in the latter situation: stuck with a half-mown yard and a smoking lawn mower in the middle of June. 

It's the same problem we have with getting regular physical check-ups when we're feeling good... but just as you don't want a major disease to be the thing that finally gets you to the doctor, wouldn't you much prefer to invest a little money, at your convenience, into preventative maintenance now instead of wait until disaster strikes your lawn mower or weed trimmer? 

The Briggs and Stratton Small Engine Care and Repair Manual suggests this regular maintenance schedule for machines with small engines:

After the first five hours of use

• Change the oil and filter

After each use

• Check the oil
• Remove debris around the muffler

Every 25 hours or every season

• Change the oil
• Service the air cleaner assembly
• Clean the fuel tank and line
• Clean the carburetor float bowl (if your machine is so equipped)
• Inspect the rewind (starter) rope for wear
• Clean the cooling fins on the engine block
• Remove debris from the blower housing
• Check engine compression
• Inspect governor springs and linkages
• Inspect ignition armature and wires
• Inspect the muffler
• Check the valve tappet clearances
• Replace the spark plug
• Adjust the carburetor
• Check the engine mounting nuts/bolts

Every 100 hours or every season

• Clean the cooling system (clean more often if using under dusty conditions)
• Change the oil filter, if equipped
• Decarbonize the cylinder head

Arco Lawn Equipment provides how-to articles, advice, and all information on this website for informational purposes only, and cannot be held liable for damage to self or equipment incurred. Please read your owner's manual, follow all safety instructions, wear proper safety apparel, and never allow children or pets to play in or around lawn equipment. Consult a professional small engine technician if you are unsure about any of the steps involved in power equipment maintenance, use, or repair.  

Overview: Types of Grass

Spring is a common time for fertilizing and reseeding your lawn; if you're going to be seeding or sodding, get an idea of what type of grass will work best in your yard first. 

Bermudagrass: One of the most commonly grown grasses, able to thrive across many zones, Bermudagrass is a warm-weather grass that is drought-tolerant. It has a long green season. Though it will tolerate drought, it will be greenest and lushest with a regular watering routine. Use a sprinkler or install an irrigation system on a timer to make routine watering easy and efficient. 

Buffalograss: Grown mainly in the Central Prairie states, this grass doesn't require mowing but isn't quite the look most suburban homeowners are going for. It does prefer sun. Turns honey-colored during colder months. 

Fescue

Fescue: Will grow across all U.S. zones and is both drought and shade tolerant. A good choice if you're working with a yard that has large areas of both sun and shade. 

Kentucky Bluegrass: Though it prefers cooler climates, Kentucky Bluegrass can be grown across the Midwest. It likes full sun, but will definitely need regular watering. 

Perennial Ryegrass: Grows across all U.S. zones. It needs sun and isn't a fan of extreme temperatures and will do best with regular watering. 

St. Augustine

St. Augustinegrass: This coarse turf grass will handle almost any warm-weather demand you can give it, from full sun to humidity. It's not a fan of frost, so you might see early browning.

Tall Fescue: A cool-season grass, Tall Fescue is drought-tolerant and will grow well in full sun or in partial shade.

Zoysia

Zoysiagrass: Another common grass; Zoysia is a warm-season grass which grows well in hot Midwest summers. It turns brown in winter, greens again in spring. 

How To: Fix a Recoil Rope Starter on Lawn Equipment

This How To will take you step-by-step through what to do if the recoil starter rope has broken and needs to be replaced on your power lawn equipment.

Step One: Prepare to work on the equipment and be safe by first disconnecting the spark plug wire from the spark plug. This will prevent accidental startups while you are working on the engine.
Make sure safety systems are in place. If you are working on a ride-on unit, make sure the brake is set and the battery is disconnected.

Step Two: Remove the starter housing or blower housing. The starter itself will have at least three fastening points. It will vary in shape depending on the machine. It is not recommended to remove any rivets if you come across them. Most housings with rivets are part of a larger housing that needs to be removed.

Step Three: Remove the leftover starter rope and inspect the starter spring. Once it is off of the machine, you can remove any old rope and test the spring by spinning or charging the spring as if the rope was being pulled out. As long as tension builds up in the spring, you are ready to put a new rope in. If the spring does not build tension you will need to install a new starter spring.

Step Four: Charge the spring and install the rope. Charge the spring as mentioned above by rotating it as if the rope was being pulled. Once tight, back the spring off one turn and put the rope into the starter through the housing and into the pulley. Tie a knot on either end ot the rope and then slowly let the rope into the starter (make sure the grip is between the two knots).

Step Five: Reinstall the starter housing on the machine and test.

Arco Lawn Equipment provides how-to articles, advice, and all information on this website for informational purposes only, and cannot be held liable for damage to self or equipment incurred. Please read your owner's manual, follow all safety instructions, wear proper safety apparel, and never allow children or pets to play in or around lawn equipment. Consult a professional small engine technician if you are unsure about any of the steps involved in power equipment maintenance, use, or repair.