Evinrude 4906B 4HP 1969, Owner'S Manual

Page: 38 / 422

Using
a
flush attachment with
a
garden hose hook-
up
to
clean the engine
water
circulation system with
fresh
water.
This arrangement may also be used while
operating the engine
at
idle speeds
to
make adjust-
ments.
Sometimes during adjustment proce-
dures, it is necessary to run the engine with
a flush device attached to the lower unit.
NEVER operate the engine over 1000 rpm
with a flush device attached, because the
engine may "RUN-A-WA Y" due to the no-
load condition on the propeller. A "run-a-
way" engine could be severely damaged. As
the name implies, the flush device is pri-
marily used to flush the engine after use in
salt water or contaminated fresh water.
Regular use of the flush device will prevent
salt or silt deposits from accumulating in
the water passageway. During and immedi-
ately after flushing, keep the motor in an
upright position until all of the water has
drained from the drive shaft housing. This
will prevent water from entering the power
head by way of the drive shaft housing and
the exhaust ports, during the flush. It will
also prevent residual water from being trap-
ped in the drive shaft housing and other
passageways.
To test the water pump, the lower unit
MUST be placed in a test tank or the boat
moved into a body of water. The pump must
now work to supply a volume to the engine.
Small horsepower engine showing debris, including
fish line, wrapped around the propeller Shaft. Entangl-
ed
fish line can cut through the oil seal behind the
propeller causing loss
of
lubricant from the lower unit.
PROPELLER 2-13
Water pump installed
on a
small horsepower lower
unit.
Lack of adequate water supply from the
water pump thru the engine will cause any
number of power head failures, such as
stuck rings, scored cylinder walls, burned
pistons, etc.
2-13 PROPELLER
Check the propeller blades for nicks,
cracks, or bent condition. If the propeller is
damaged, the local mar ine dealer can make
repairs or send it out to a shop specializing
in such work.
Example
of a
damaged propeller. This unit should
have been replaced long before this amount
of
damage
was sustained.