SECTION VIII
POWER PLANT
8-1. INTRODUCTION. This section covers the power plant used in the PA-28-161 CADET airplane, and is
comprised of instructions for the removal and installation, minor repairs and service of the propeller, engine,
induction system components, ignition system components and engine lubrication system.
For further instructions and for major repairs, consult the appropriate publications of the engine or
component manufacturer.
8-2. DESCRIPTION. The PA-28-161 CADET is powered by an Avco-Lycoming engine, of 160 horsepower
(Refer to Power Plant Specifications in table 11-1.) The engine is an 0-320 series, four cylinder, wet sump,
horizontally opposed, direct drive, air cooled power plant. The cylinders are not directly opposed from each
other but are staggered, thus permitting a separate throw on the crankshaft for each connecting rod.
The propeller installed on the aircraft is a fixed pitch type. (Refer to Table 11-1 for Propeller Specifications).
The induction system on these engines consists of a wet type air filter, a Marvel-Schebler float type
carburetor and a diaphragm type fuel pump. (Refer to Table 11-1 for Specifications).
The magneto used on these engines may be either Slick 4000 series, Slick 4200 series. The Slick 4000 series
magnetos are installed with their associated components. These magnetos are engineered to give trouble free
ignition, and are exchanged for factory rebuilt units upon engine overhaul, for a nominal cost. These magnetos
are non-serviceable units. The 4200 series magnetos are completely self contained and consist of impulse
coupling on the left magneto to aid in starting. These magnetos are serviceable units.
In addition to the previously mentioned components, each engine is furnished with a starter, 60 ampere
alternator, 14 volt electrical system, shielded ignition, vacuum pump drive and fuel pump. The exhaust system is
stainless steel with two mufflers. A shroud is provided to supply heat for both the cabin and carburetor.
The lubrication system is the pressure wet sump type. The oil pump is located in the accessory housing and
draws oil through a drilled passage leading from the oil suction screen located in the sump. The oil from the
pump then enters a drilled passage in the accessory housing, which feeds the oil to a threaded connection on the
rear face of the accessory housing, where a flexible line leads the oil to the external oil cooler. Pressure oil from
the cooler returns to a second threaded connection on the accessory housing from which point a drilled passage
conducts the oil through the pressure screen or filter. In the event that cold oil or an obstruction should restrict
the flow of oil to the cooler, an oil by-pass also is provided to pass the oil directly from the oil pump to the oil
pressure screen or filter.
The oil pressure screen or filter element, located on the accessory housing is provided as a means to filter any
solid particles from the oil that may have passed through the suction screen in the sump. After being filtered, the
oil is fed through a drilled passage to the oil pressure relief valve, located in the upper right side of the crankcase
in front of the accessory housing. This relief valve regulates the engine oil pressure by allowing excess oil to
return to the sump while the balance of the pressure oil is fed to the main oil gallery in the right half of the
crankcase. Residual oil is returned by gravity to the sump where, after passing through the suction screen in the
sump, it is again circulated through the engine.
PIPER AIRCRAFT
PA-28-161 CADET
AIRPLANE MAINTENANCE MANUAL
Issued: FEBRUARY. 28, 1989
POWER PLANT
1J5
