Section 7
Description of the Airplane and Systems
Columbia 400 (LC41-550FG)
RC050002
Initial Issue of Manual: November 10, 2004
7-22
Latest Revision Level/Date: -/11-10-2004
about 180
°
F (82
°
C). Ram air for the oil cooler is provided by the engine’s pressure cooling
system.
The term “wet sump” means the oil is stored within the engine sump as opposed to a separate oil
tank. The oil is drawn out of the sump by the engine-driven oil pump where it is sent to a full
flow oil filter, i.e., a filter that forces all the oil to pass through the filter each time it circulates.
The system pressure is kept constant by a spring-loaded pressure relief valve that is between the
pump and the filter. From the oil filter, the oil flows into the oil cooler if the temperature is high
enough and then is routed to the left oil gallery (an oil dispersal channel or passage). The oil in
the left gallery flows forward to the front of the engine and a portion of the flow is sent to the
propeller governor. The oil flow is then directed to the right engine gallery and flows towards the
rear of the engine and back to the oil sump.
Oil within the left and right galleries is injected onto the crankshaft, camshaft, propshaft bearing,
accessory drive bearings, cylinder walls, and other various parts within the engine. After
lubricating the engine, gravity causes the oil to flow downward through transfer tubes and drain
holes where it is returned to the oil sump.
If the filter becomes clogged and prevents oil from moving through the system, a bypass valve
reroutes the oil around the filter. In this event, the lubricating oil is, of course, unfiltered.
However, rerouting the oil will prevent engine failure. It is important to note that the pilot will
have no indication that the oil filter has clogged, and this situation compounds the problem.
Since the filter failure was most likely caused by contaminated oil, the oil system will be
lubricated with contaminated oil. The best solution is timely and frequent oil changes.
The dipstick and oil filler cap access door are located on the top left engine cowl about two feet
from the propeller hub. The engine should not be operated with less than six quarts of oil and
must not be filled above eight quarts. For extended flights, the oil should be brought up to full
capacity. Information about oil grades, specifications, and related issues are covered in Section 8
of this handbook.
Exhaust –
Gases that remain after combustion flow from the cylinders through the exhaust
valves and into the exhaust manifold (a series of connected pipes) and are expelled into the
outside atmosphere. There is an exhaust manifold on each side of the engine, and each of the
manifolds is connected to three cylinders. The manifolds are connected to a turbocharger and tail
pipe that extend out the bottom of the engine cowling. A crossover pipe allows the exhaust gas
from the right side to flow to the left side wastegate.
