Detailed Engine Description; 2-3.1. Crankcase; Figure 2-4. Crankcase Features - Continental Motors O-200-D Installation And Operation Manual

Engine Description
2-3.

Detailed Engine Description

2-3.1. Crankcase

Two aluminum alloy castings are joined along the vertical center plane to form the
crankcase. The individual castings (with studs and inserts) are referred to as the "left
crankcase" and "right crankcase." The crankcase provides a tight enclosure, sufficiently
rigid to support the crankshaft, camshaft and bearings, with oil galleries for lubrication.
The upper and lower backbones (spines) are sealed by fourteen hex head screws, washers,
and plain nuts, two of which attach the engine lifting eye to the upper flanges. Each
casting has two machined cylinder mount pads. Cylinder openings in pads on the two
sides of the case are offset to align with the connecting rod journal for each piston.
Cylinder pads and case webs are stiffened by integral ribs cast in the crankcase. A
counterbore around the crankshaft opening in the front of the case receives the crankshaft
oil seal. A groove at each end of the front main bearing boss accommodates thrusts
washers.
Saddles for precision steel-backed crankshaft main bearing inserts are line bored through
web bosses. Camshaft bearings are bored directly in the case metal. Bearings are divided
equally by the parting surface, camshaft bearings being directly below the main bearings.
Crankcase halves are retained by through studs installed in the bosses above and below the
front and rear main bearings, two through bolts installed in lieu of two through studs at the
center bearing bosses and one through stud below the rear camshaft bearing. In addition to
the through studs and through bolts, cylinder mount pads have short studs to secure the
cylinder to the crankcase.
2-4 OR L/H 2-4 OR L/H
CRANKCASE HALF CRANKCASE HALF
REAR CRANKSHFT REAR CRANKSHFT REAR CRANKSHFT
BEARING BORE BEARING BORE BEARING BORE
TAPPET TAPPET
GUIDES GUIDES
ACCESSORY CASE ACCESSORY CASE
MOUNT FLANGE MOUNT FLANGE
2-10
BACKBONE BACKBONE
Cyl #2 Cyl #2 Cyl #2
CAMSHAFT CAMSHAFT
BEARING BORE BEARING BORE
OIL SUMP OIL SUMP
MOUNT FLANGE MOUNT FLANGE

Figure 2-4. Crankcase Features

O-200-D & X Series Engine Installation and Operation Manual
INTERMEDIATE INTERMEDIATE
CRANKSHAFT BEARING BORE CRANKSHAFT BEARING BORE
CRANKSHAFT NOSE CRANKSHAFT NOSE
SEAL LAND SEAL LAND
Cyl #4 Cyl #4 Cyl #4
TAPPET TAPPET
CAMSHAFT CAMSHAFT
GUIDES GUIDES
BEARING BORE BEARING BORE
SPINE BELOW SPINE BELOW
CAMSHAFT CAMSHAFT
FRONT FRONT
CRANKSHAFT CRANKSHAFT
BEARING BORE BEARING BORE
3 January 2017