Lycoming O-320 76 Series Operator's Manual page 34

SECTION 4
PERIODIC INSPECTIONS
1. DAILY PRE-FLIGHT.
a. Be sure all switches are in the "Off" position.
b. Be sure magneto ground wires are connected.
c. Check oil level.
d. See that fuel tanks are full.
e. Check fuel and oil line connections, note minor indications for repair at 50-hour inspection. Repair
any leaks before aircraft is flown.
f. Open the fuel drain to remove any accumulation of water and sediment.
g. Make sure all shields and cowling are in place and secure. If any are missing or damaged, repair or
replacement should be made before the aircraft is flown.
h. Check controls for general condition, travel and freedom of operation.
i. Induction system air filter should be inspected and serviced in accordance with the airframe
manufacturer's recommendations.
2. 25-HOUR INSPECTION. After the first twenty-five hours operating time, new, rebuilt or newly
overhauled engines should undergo a 50-hour inspection including draining and renewing lubricating oil.
3. 50-HOUR INSPECTION. In addition to the items listed for daily pre-flight inspection, the following
maintenance checks should be made after every 50 hours of operation.
a. Ignition System –
(1) If fouling of spark plugs has been apparent, rotate bottom plugs to top position.
(2) Examine spark plug leads of cable and ceramics for corrosion and deposits. This condition is
evidence of either leaking spark plugs, improper cleaning of the spark plug walls or connector
ends. Where this condition is found, clean the cable ends, spark plug walls and ceramics with a
dry, clean cloth or a clean cloth moistened with methyl-ethyl-ketone. All parts should be clean and
dry before reassembly.
(3) Check ignition harness for security of mounting clamps and be sure connections are tight at spark
plug and magneto terminals.
b. Fuel and Induction System – Check the primer lines for leaks and security of the clamps. Remove and
clean the fuel inlet strainers. Check the mixture control and throttle linkage for travel, freedom of
movement, security of the clamps and lubricate if necessary. Check the air intake ducts for leaks,
security, filter damage; evidence of dust or other solid material in the ducts is indicative of inadequate
filter care or damaged filter. Check vent lines for evidence of fuel or oil seepage; if present, fuel pump
may require replacement.
4-2
LYCOMING SERIES OPERATOR'S MANUAL
O-320