Teledyne Continental Motors, Inc.
TM
Engine
Description
IOF-550 Permold Series Engine Maintenance Manual
2-3
1 April 2007
2-1.
General Engine Description
IOF-550 Permold Series engines are six cylinder, fuel injected, horizontally opposed, air
cooled engines designed for variable-pitch propeller applications. These air-cooled,
horizontally-opposed engines are equipped with a Full Authority Digital Engine Control
(FADEC) System for continuously monitoring and controlling ignition timing, fuel
injection timing, and fuel mixture. The engine cylinders are cross flow design having
overhead inclined valves. The cylinders have downdraft intake inlets mounted on the top
of the cylinder head and downdraft exhaust outlets located on the bottom of the cylinder.
The IOF-550 Permold Series engines have a 550 cubic inch displacement achieved by
using a cylinder design with a 5.25 inch diameter bore and a 4.25 inch stroke. The IOF-
550 engine enclosure utilizes the Permold Series crankcase design. The engine dry
weight is ranges from 447.1 to 470.5, depending on configuration, without accessories.
See the detailed model specification and accessory specification for total weight with
accessories.
A key distinguishing feature of Permold engines is the camshaft serves as the main oil
gallery, distributing oil throughout the crankcase. Another characteristic feature of
Permold engines is the alternator is mounted on the front of the right crankcase half,
while the oil cooler is mounted on the rear of the left crankcase half. Depending on
airframe requirements, Permold engines utilize either a cast aluminum or stamped
aluminum oil sump attached to the bottom of the crankcase.
The engine is provided with four engine mounts designed for a focalized bed mount; an
optional six-point mount is available. A crankcase breather port is located on the oil filler
neck on the 2-4-6 side of the crankcase between number 2 and number 4 cylinders. A
.374-24 UNF threaded port is located near the bottom side of the cylinder head for use
with a bayonet thermocouple.
The engine lubrication system is a wet sump, high pressure oil system. The engine
lubrication system includes the internal engine driven pressure oil pump, engine mounted
oil cooler, oil sump, full flow oil filter, oil pressure relief valve, and pressure
instrumentation. The oil cooler is mounted on the left crankcase half behind the number 2
cylinder. A vernatherm valve allows oil flow into the engine if an oil restriction occurs in
the external oil cooler and during cold starting.
The IOF-550 Permold Series engines incorporate a downdraft balanced port induction
system with an engine mounted throttle body. Engine manifold pressure is controlled by
the throttle plate and is measured by two manifold air pressure sensors mounted in .125 -
27 NPTF bosses located on the induction manifold near the throttle.
The IOF-550 Permold Series engine requires a customer provided exhaust system.
The microprocessor-based FADEC System monitors engine operating conditions and
then automatically sets the fuel mixture and ignition timing accordingly for any given
power setting. Consequently, engines equipped with the FADEC System do not require
magnetos and eliminates the need for manual fuel/air mixture control.
