Evinrude 4906B 4HP 1969 Owner's Manual page 46

Parts MUST be cleaned and thoroughly in-
spected before they are assembled,
ed, or adjusted. Use proper lubricants,
their equivalent, whenever they are recom-
mended.
Keep rods and rod caps together as a set
to ensure they will be installed as a pair and
in the proper sequence.
Needle bearings MUST remain as a com-
plete set. NEVER mix needles from one set
with another. If only one needle is damag-
ed, the complete set MUST be replaced.
3-3 POWERHEAD
Preliminary Work
Before the powerhead can be disassembl-
ed, the battery must be disconnected;
lines disconnected; and the carburetor,
erator, starter, flywheel, and magneto,
removed. If in doubt as to how these items
are to be removed, refer to the appropriate
chapter.
After the accessories
ed, remove the bolts in the front and rear of
the power head securing
the exhaust housing.
free.
BAD NEWS
If the unit is several years old, or if it
has been operated in salt water, or has not
had proper maintenance,
number of other factors, then separating the
powerhead from the exhaust
not be a simple task.
be required on the studs to shake the corro-
sion loose; heat may have to be applied to
Removing the head from the cylinder block.
install-
DISASSEMBLING
fuel
gen-
have been remov-
the powerhead
Lift the power head
or shelter, or any
housing may
An air hammer may
or
Cylinder block water passages corroded preventing
proper circulation
the casting to expand it slightly; or other
devices employed
powerhead.
would be the driveshaft
all
crankshaft.
type hole must be drilled and a torch used to
cut the driveshaft.
head will come free on the first attempt.
The following
to
work after
been completed.
3-4 HEAD
Usually the head is removed and an ex-
amination
mine the extent of overhaul required.
ever, if the head has not been removed,
back out all of the head bolts and lift the
head free of the powerhead,
A compression release chamber being removed from
an
the head on
DISASSEMBLING
of
coolant water.
in order to remove the
One very serious
"frozen" with the
In this case, a circular
Let's assume the power-
procedures
these preliminary
SERVICE
of the cylinders made to deter-
35
early model hp engine.
3-5
condition
plug-
pickup the
tasks have
How-