Power Plant Description; Power Plant Troubleshooting - Piper PA-44-180 SEMINOLE Maintenance Manual

GENERAL.
This chapter covers the power plants used in this airplane, and is comprised of instructions for the removal
and installation, minor repairs, and service.
DESCRIPTION.
The PA-44-180, s/n's 44-7995001 through 44-8195026 are powered by two O-360-ElA6D or LO-360-
ElA6D Textron Lycoming engines rated at 180 horsepower each. S/n's 4495001 and up are equipped with
two O-360-A1H6 or LO-360-A1H6 Textron Lycoming engines rated at 180 horsepower each.
To ensure adequate outflow through oil breather tube on
-AIH6 engines, do not permit cutout in shroud around
breather vent holes to become blocked.
The -A1H6 model engines have the oil breather pipe wrapped in a sheath to decrease the probability of
condensation freezing and blocking the pipe during winter operations. (Refer to Figure 71-1, Sheet 2 of 3.)
Both model power plants used on the PA-44-180 are four cylinder, horizontally opposed units. See
Chapter 6, Leading Particulars, for the differences between these two engine models operating limits.
The PA-44-180T Turbocharged Seminole uses TO360-E1A6D and LTO 360-E1A6D Textron Lycoming
engines. These engines are very similar to those used in the normally aspirated version with the exception of
the turbocharger and related peculiarities. Notable differences involve a sniffle valve, change in timing, and a
change in maximum permissible oil pressure during engine start and warmup. The turbocharged version is set
to maintain 75%, power to approximately 20,000 ft. density altitude. This engine also incorporates a bypass
overboost valve but should not be adjusted except by Lycoming procedures. Induction air is forced through
an Airsearch TA04 t u rb o c h a rger where it is compressed prior to reaching the carburetor. Leading particulars on
the engine can be found in Chart 601 in Chapter 6.
The propellers installed are Hartzell constant speed units. (Refer to Chapter 61 for complete detail and
service information.) The induction system on these engines consists of Marvel-Schebler HA-6 float type
c a rburetors with dry type air filters. Also incorporated with the carburetor on the PA-44-180, s/n's
4 4 -7995001 through 44-8195026, is a Piper installed carburetor ice detector.
The magnetos are:
1. PA-44-180, s/n's:
A . 44-7995001 through 44-8195026 (Right Engine) = Bendix D4RN-2021 or D4RN 3021 (LW- 3 8 2 5 5 5 - 1 4 )
B. 4495001 and up = Refer to Textron Lycoming Manuals (Slick 4270, 4273, 4202, 4230 Series).
2. PA-44-180T, s/n's
A. 44-8107001 through 44-8107049 = Bendix D4RN-2021 D 4 L N - 2 0 2 1
B . 44-8107050 and up = Bendix D4RN 3021 or D4LN 3021
The Bendix magneto is a dual magneto utilizing a single drive. It incorporates an impulse coupling to p r o v i d e
ignition at engine cranking speed. The engines on the PA-44-180, s/n's 4495001 and up, utilize individual
left and right magneto with individual drives. The left magneto incorporates an impulse coupling to provide
ignition at engine cranking speed. (Refer to Chapter 74 for detailed information.)
TROUBLESHOOTING.
Troubles peculiar to the power plant are listed in Chart 7101 of this chapter, and consists of Tr o u b l e s ,
Probable Causes and Suggested Remedies. When troubleshooting these engines ground the magneto primary
circuit before performing any checks on the engines.
PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
— CAUTION —
(Left Engine) = Bendix D4LN-2021 or D4LN 3021 (LW- 3 8 2 5 5 5 -1 4 ))
3D23
71-02-00
Page 71-01
Revised: June 20, 1995