New Engine Break In And Operation; Engine Lubrication System - Cessna 172R Pilot Operating Handbook

NEW ENGINE BREAK IN AND OPERATION
The engine underwent a run in at the factory and is ready for the
full
range of
use. lt is, however, suggested that cruising be
accomplished at 80% power as much as practicable until a total of
50 hours has accumulated or oil consumption has stabilized. This
will ensure proper seating of the rings.
ENGINE LUBRICATION SYSTEM
The engine utilizes a full pressure, wet sump type lubrication
system with aviation grade oil used as the lubricant. The capacity of
the engine sump (located on the bottom of the engine) is eight
quarts. Oil is drawn from the sump through an oil suction strainer
screen into the engine driven oil pump. From the pump, oil is routed
to a bypass valve. If the oil is cold, the bypass valve allows the oil to
bypass the oil cooler and go directly from the pump to the full flow
oil filter. If the oil is hot, the bypass valve routes the oil out of the
accessory housing and into a flexible hose leading to the oil cooler
on the right, rear engine baffle. Pressure oil from the cooler returns
to the accessory housing where it passes through the full flow oil
filter. The filter
oil
then enters a pressure relief valve which
regulates engine oil pressure by allowing excessive oil to return to
the sump while the balance of the oil is circulated to various engine
parts for lubrication. Residual oil is returned to the sump by gravity
flow.
An oil filler cap/oil dipstick is located at the right rear of the
engine. The filler cap/ dipstick is accessible through an access door
on the top right side of the engine cowling. The engine should not
be operated on less than five quarts of oil. For extended flight, fill to
eight quarts (dipstick indication only). For engine oil grade and
specifications, refer to Section 8 of this handbook.
Dec 2/96
7-21
CESSNA
SECTION 7
MODEL 172R
AIRPLANE & SYSTEMS DESCRIPTION