Spark Plug

WARNING! DO NOT check for spark with spark plug removed. DO NOT crank engine with spark plug removed.

WARNING! If the engine has been running, the muffler will be very hot. Be careful not to touch the muffler.

To ensure proper engine operation, the spark plug must be properly gapped and free of deposits.

1.Remove the spark plug boot and use a spark plug wrench to remove the plug, Figure 7-2.

Spark Plug

4.Check that the spark plug washer is in good condition and thread the spark plug in by hand to prevent cross- threading.

5.After the spark plug is seated, tighten with a spark plug wrench to compress the washer.

NOTE: When installing a new spark plug, tighten 1⁄2-turn after the spark plug seats to compress the washer. When reinstalling a used spark plug, tighten 1⁄8- to 1⁄4-turn after the spark plug seats to compress the washer.

caution! The spark plug must be tightened securely. A loose spark plug can become very hot and can damage the engine.

Cleaning the Engine

If the engine has been running, allow it to cool for at least half an hour before cleaning. Periodically remove dirt build-up from engine.

CAUTION! Do not spray engine with water to clean because water could contaminate fuel. Using a garden hose or pressure washing equipment can also force water into the muffler opening. Water that passes through the muffler can enter the cylinder, causing damage.

WARNING! Accumulation of debris around muffler could cause a fire. Inspect and clean before every use.

Spark Plug Boot

Figure 7-2

2.Visually inspect the spark plug. Discard the spark plug if there is apparent wear, or if the insulator is cracked or chipped. Clean the spark plug with a wire brush if it is to be reused.

3.Measure the plug gap with a feeler gauge. Correct as necessary by bending side electrode, Figure 7-3. The gap should be set to .02-.03 inches (0.60-0.80 mm).

Electrode

.02-.03 in.

(0.60-0.80 mm)

Figure 7-3

Off-Season Storage

Engines stored over 30 days need to be drained of fuel to prevent deterioration and gum from forming in fuel system or on essential carburetor parts. If the gasoline in your engine deteriorates during storage, you may need to have the carburetor, and other fuel system components, serviced or replaced.

1.Remove all fuel from tank by running engine until it stops.

2.Change the engine oil.

3.Remove spark plug and pour approximately 1 oz. (30 ml) of clean engine oil into the cylinder. Pull the recoil starter several times to distribute the oil, and reinstall the spark plug.

4.Clean debris from around engine, and under, around, and behind muffler. Apply a light film of oil on any areas that are susceptible to rust.

•Store in a clean, dry and well ventilated area away from any appliance that operates with a flame or pilot light, such as a furnace, water heater, or clothes dryer. Avoid any area with a spark producing electric motor, or where power tools are operated.

•If possible, avoid storage areas with high humidity.

•Keep the engine level in storage. Tilting can cause fuel or oil leakage.

Section 7 — Engine Maintenance

 

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