Piston Rings - Honda CB350 Repair Manual

ENGINE AND TRANSMISSION
Checking wrist pin diameter
service limit given. If worn past the ser—
vice limit, the connecting rod must be re—
placed, along with the crankshaft on 350
models. On 360 models, the crankshaft
can be
disassembled
and
assembled
using a crankshaft press, this operation
should only be done by a Honda dealer
with the proper equipment.
9. Although not as conclusive as a
direct measurement, the condition of the
wrist pin and the small end can be
checked by inserting the wrist pin into
the small end and checking for vertical
movement. There should be no notice—
able play. Ifthere is noticeable movement
in the pin, eitherit or the rod, or both, are
in need of replacement. If the rod small
end is discolored or scored, it may have
to be replaced.
Check the connecting rods for a bent
condition.
This can be accomplished by obtaining
two small blocks of metal of exactly the
same thickness. Place these pieces across
the crankcase opening (from front to rear)
below the small end. Place the wrist pin
into the connecting rod, and lower it so
that it rests on the blocks. The wrist pin
must touch both blocks. Ifit does not, the
con rod is bent and must be replaced.
10. Before
installation,
decarbonize
the piston crown. Remove any carbon
from the piston ring grooves with a piece
of broken ring or a small screwdriver. Be
careful not to scratch or widen the groove
as this is done. Carefully check the cylin—
der, cleaning the bores thoroughly with
an oil—soaked rag. Remove any traces of
gasket material from the cylinder base
and
from
the crankcase
mating
sur—
face.
11. Be sure that all oil passages in the
Cleaning out the ring grooves with a piece of
broken ring
Piston Rings
Three checks to be made to the piston
rings are side clearance, ring thickness
(350), and ring end—gap. These checks
should be made to both new and used
rings.
1. Piston
ring
side clearance
is
checked with the piston rings installed
on the piston. Insert a feeler gauge blade
Checking ring side clearance