General - Cub Crafters CC18-180 Maintenance Manual

1. GENERAL

The fuel system is a gravity flow system. Fuel drains from two wing tanks through a selector
valve and fuel strainer to the carburetor.
There is an engine fuel primer system that may be used to start the engine, especially in cold
conditions. The fuel primer draws fuel from the strainer by means of a hand-operated pump on
the instrument panel and injects it into three cylinders for starting.
The selector valve is located on the lower left side of the cockpit and has four positions;

Both - The engine is fed by both fuel tanks

Left - Fuel is supplied by the left tank.

Right - Fuel is supplied by the right tank.

Off - Fuel supply to the engine is cut off.
Fuel will flow from one tank to the other when the selector is in either the "OFF" or the "BOTH"
position. The fuel vent lines are fitted with check valves, which will prevent fuel from being
discharged when tanks are full and the aircraft is in uncoordinated flight or when it is parked on
a slope. When parking the aircraft on a slope, leave the selector either in the "LEFT" or
"RIGHT" positions to prevent fuel from flowing from one tank to the other.
The engine may be operated in the BOTH, LEFT, or RIGHT positions. However, the selector
must be in the "BOTH" position for takeoff and landing.
The fuel strainer is equipped with a quick drain and is mounted on the engine side of the
firewall.
Fuel quantity is determined by means of two glass sight gauges located on either side of the
cockpit at the wing root.
The tanks are ventilated through tubes at the forward outboard edge of the tanks. The tubes
protrude under the wing, close to the forward wing strut attachment. Also an interconnect vent
line goes between them crossing behind the rear spar carry through.
Prior to refueling the aircraft, connect the fueling equipment's grounding wire to either of the
wing tie downs
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CUB CRAFTERS, INC.
CC18-180 MAINTENANCE MANUAL
Manual number TC10000AMM
Date: 04/16/08