CAPITOL HY- 6900, Service Manual

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10
2.5 HYDRAULIC SYSTEM
is drawn from the sump through a suction
hose and then sent under pressure to a filter
and an oil cooler and the to the selector
valve. The selector valve is used to obtain
forward, neutral or reverse by routing the
high-pressure oil through internal passages
to the clutch. Low-pressure oil is channeled
to cool bearings, gears and clutch discs. An
oil dam keeps the transmission oil within the
transmission housing.
In neutral the ports to both the forward and
reverse sides of the clutch cylinder are
opened and the balanced pressure that
results keeps the clutch cylinder centered
between the forward and reverse clutch
discs. Oil is distributed through the
lubrication system.
When the selector valve is shifted to either
forward or reverse mode high pressure oil is
allowed to flow only to one half of the clutch
cylinder to engage the selected pack. Oil in
the other half of the cylinder is exhausted to
sump. In forward or reverse, oil is also
distributed through the lubrication system.