Onan CCK Series - Maintenance and Repair Continued; Cylinder Repair and Piston Replacement

62
MAINTENANCE AND REPAIR
THESE MARKS MUST
COINCIOE WHEN IN~
STALLING TIMING
GEARS.
SCREWS PASS THROUGH
\lEAR ANO BEAR
AGAINST CRANK-
SH~FT ~nv'"v~"_
FIG. 43 - TIMING GEARS
The camshaft gear is pressed on and keyed to the camshaft. The cam-
shaft and gear must be removed as an assembly, after first removing
the crankshaft gear lock ring and washer. Before removing the cam-
shaft and gear assembly, remove the cylinder head and valve assem-
blies. Remove the operating plunger for the breaker points. Remove
the fuel pump and tappets. After removing the-governor cup assembly
from the gear, the camshaft may be pressed out of the gear by use of a
hollow
tool or pipe which will fit over the camshaft center pin. Do not
press on the center pin or damage it in any way.. The governor ball
spacer is a press fit to the camshaft .gear.
When
pressing a camshaft gear onto the camshaft, be sure the gear is
. started straight and thaUhe key is properly: in place. Install the gov-
. ernor cup assembly before installing the camshaft and gear. in the en-
.gine. . .
Note that each timing gear is stamped'with "0" mark near the edge. The
gear teeth must mesh so that these marks exactly coincide when the gears
are installed in the engirie. Be sure, when installing the camshaft gear
and shaft assembly,' that the thrust washer is properly in place behind
the camshaft gear. Replace the retaining washer and lock ring to the
crankshaft.
CYLINDER, - The cylinder wears very little in normal service. If
through improper lubrication or accident, the cylinder
wall should become' scored or worn badly, the cylinder may be rebored
and.honed to accomodate a new piston and rings of one of the available
oversizes. Pistons and rings are available in .010",.020", and .030"
oversizes. An engine may have been fitted at the factory with .005"
overSize pistons, and will be so indicated by the letter "E" following
the engine serial number stamped on the cylinder block and on the plant
nameplate. Use standard size rings on a .005
ff
oversize piston. If the