MTD 41M ユーザーズマニュアル

3. 

Measure the plug gap with a feeler gauge. Correct as 
necessary by bending side electrode. See Fig. 10-4. The 
gap should be set to 0.030 in.

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 1/8-1/4 turn after the 
spark plug seats to compress the washer.
IMPORTANT: The spark plug must be securely tightened.
An improperly tightened spark plug can become very hot 
and may damage the engine.

DO NOT check for spark with spark 

plug removed. DO NOT crank engine with spark 
plug removed.

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

Remove the spark plug boot and use a spark plug wrench 
to remove the plug. See Fig. 10-3.

If the engine has been running, the 

muffler will be very hot. Be careful not to touch the 
muffler.

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.

1.