Engine Description
Teledyne Continental Motors, Inc.
TM
2-8
IOF-550 Permold Series Engine Maintenance Manual
1 April 2007
The portion of the rod between the rod and the crankpin and piston pin ends is called the
“I” beam. A split steel-backed bronze bushing is pressed into the piston pin end and
machined for a precision pin-to-bushing fit. Weight variations between opposing
crankshaft positions is limited to ½ ounce (14.175 grams).
NOTE: Some older models use castellated nut with cotter pin
SPIRAL LOCK NUT
BRONZE BUSHING
CONNECTING ROD
CONNECTING ROD
CAP
ROD BOLT
SHELL
BEARING
2-2.2.3. Camshaft
The camshaft is machined from an aircraft quality steel casting. The forging is machined
on four main journals, nine cam lobes and a gear mounted flange at the rear of the
camshaft. The main journals ride within the crankcase camshaft bores. The hydraulic
tappet movement inward and outward in there bores is caused by the eccentric camshaft
lobes. The lobes and journals are ground and hardened. Movement of the tappets opens
and closes the intake and exhaust valves within the cylinder head by mechanical linkage
of the pushrods and rocker arms. The exact moment of valves opening and closing is
synchronized by the crankshaft to camshaft timing. Four unequally spaced bolts retaining
the gear to the camshaft ensure proper positioning, locating the gears’ timing mark in
relation to the cam lobes. The camshaft gear incorporates a splined drive for the engine
oil pump. A front mounted keyed bevel drive gear provides momentum for the prop
governor bevel driven gear.
MJ
MJ
MJ
MJ
CL
CL
CL
CL
CL
CL
CL
CL
CL
GOVERNOR
DRIVE GEAR
CAMSHAFT
GEAR
OIL PUMP DRIVE
SHAFT PROVISION
#6
EXH
#5 INT
#6 INT
#5
EXH
#4
EXH
#3 INT
#4 INT
#3
EXH
#2
EXH
#2 INT
#1 INT
#1
EXH
2-2.2.4. Idler Gear
The idler gear support pin supports the idler gear. The bushing in the crankcase supports
the forward part of the idler gear support pin shaft. The crankshaft drives the idler gear
directly. In turn, the idler gear drives the left and right magneto accessory drive gears.