Spark Plug Service; Cleaning The Engine - MTD 277cc Operator's Manual

Spark Plug Service

WARNING: DO NOT check for spark
with spark plug removed. DO NOT
crank engine with spark plug removed.
WARNING: If the engine has been run-
ning, 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 3-2.
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
3-3. The gap should be set to 0.02-0.03 inches
(0.60-0.80 mm).
4. Check that the spark plug washer is in good condi-
tion 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
1/8-1/4 turn after the spark plug seats to compress
the washer.
IMPORTANT: The spark plug must be tightened
securely. An 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.
IMPORTANT: 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
Figure 3-2: The spark plug and boot.
Electrode
0.02-0.03 in.
0.60-0.80 mm
Figure 3-3: Use a feeler gauge to measure the plug gap.
11
Maintaining
Spark Plug Boot
WARNING
DO NOT check for spark
with spark plug removed.
DO NOT crank engine
with spark plug removed.
If the engine has been
running, the muffler will
be very hot. Be careful
not to touch the muffler.
3
the
Engine