Piper PA-28-161, Maintenance Manual

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PIPER AIRCRAFT, INC.
PA-28-161, WARRIOR III
MAINTENANCE MANUAL
PAGE 1
Nov 30/06 4I23
71-00-00
GENERAL
WARNING: FAILURE TO CONSULT APPLICABLE VENDOR PUBLICATION(S), WHEN SERVICING
OR INSPECTING VENDOR EQUIPMENT INSTALLED IN PIPER AIRCRAFT, MAY
RENDER THE AIRCRAFT UNAIRWORTHY. (SEE INTRODUCTION - SUPPLEMENTARY
PUBLICATIONS.)
This chapter covers power plant removal, installation, and service. Ignition system components and the
engine lubrication system are covered in Chapters 74 and 79, respectively.
1. Description (See also Chart 1, 6-00-00.)
The PA-28-161 is powered by a Textron-Lycoming engine, of 160 horsepower. This power plant is an
0-320 series, four cylinder, wet sump, horizontally opposed, direct drive, air-cooled engine. 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 fixed pitch, all metal.
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.
Slick 4300 series magnetos are installed with their associated components. These magnetos are
completely self contained and includes an impulse coupling on the left magneto to aid in starting. They
are engineered to give trouble free ignition, and can be exchanged, at a nominal cost, for factory rebuilt
units upon engine overhaul.
In addition to the previously mentioned components, each engine installed in the Warrior III is equipped
with a 28 volt 70 ampere alternator, providing the airplane with a 28 Vdc electrical system. A shielded
ignition, vacuum pump drive, fuel pump and starter are also provided. 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 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.
2. Troubleshooting
WARNING: GROUND THE MAGNETO PRIMARY CIRCUIT BEFORE PERFORMING ANY CHECKS
OF THE ENGINE.
Troubles peculiar to the power plant are listed in Chart 1 along with their probable causes and suggested
remedies.