Craftsman 247.37683 - Manual (Page 17)

SERVICE AND MAINTENANCE
A
warning
Always stop engine, disconnect spark plug wire, and ground against
engine before performing any type of maintenance on your machine.
GENERAL RECOMMENDATIONS
• Always observe safety rules when performing any maintenance.
• The warranty on this lawn mower does not cover items that have
been subjected to operator abuse or negligence. To receive full
value from warranty, operator must maintain the equipment as
instructed here.
• Changing of engine-governed speed will void engine warranty.
• All adjustments should be checked at least once each season.
• Periodically check all fasteners and make sure these are tight.
ENGINE MAINTENANCE
Spark Plug
NOTE: Incorrect spark plugs can cause engine damage.
For good performance, the spark plug must be properly gapped and
free of deposits. Check the spark plug every 50 hours or once a
season. Replace the spark plug every 200 hours of operation.
1. Disconnect the cap from the spark plug, and remove any dirt from
the spark plug area.
2. Use the proper size spark plug wrench to remove the spark plug.
3. Inspect the spark plug. Replace it it damaged, badly fouled, it the
sealing washer is in poor condition, or if the electrode is worn.
4. Measure the electrode gap with a suitable gauge. The correct gap
is 0.028 - 0.030 in. (0.70 - 0.80 mm). See Figure 12. If adjustment
is needed, correct the gap by carefully bending the side electrode.
5. Install the spark plug carefully, by hand, to avoid cross-threading.
6. After the spark plug is seated, tighten with the proper size spark
plug wrench to compress the washer.
When installing a new spark plug, tighten 1/2 turn after the spark plug
seats to compress the washer.
When reinstalling the original spark plug, tighten 1/8-1/4 turn after the
spark plug seats to compress the washer.
NOTE: Properly tighten the spark plug. A loose spark plug can become
very hot and can damage the engine. Overtightening the spark plug
can damage the threads in the cylinder head.
7. Attach the spark plug cap to the spark plug.
Air Cleaner
A dirty air cleaner will restrict airflow to the carburetor and cause poor
engine performance. Inspect the filter each time the engine is oper­
ated. You will need to clean the filter more frequently it you operate the
engine in very dusty areas.
Clean the air cleaner every 25 hours of operation or once a season.
Replace the air cleaner every 200 hours of operation.
NOTE: Operating the engine without a filter, or with damaged filter, will
allow dirt to enter the engine, causing rapid engine wear.
Inspection
1. Press the latch tabs on the top of the air cleaner cover, and
remove the cover. Check the filter to be sure it is clean and in
good condition. See Figure 13.
2. Reinstall the filter and air cleaner cover.
Cleaning
Tap the filter several times on a hard surface to remove dirt, or
blow compressed air not exceeding 30 psi through the filter from
the clean side that faces the engine. Never try to brush off dirt.
Brushing will force dirt into the fibers.
Wipe dirt from the air cleaner body and cover using a moist rag.
Be careful to prevent dirt from entering the air duct that leads to
the carburetor.
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