Westerbeke 6.5KW Technical Manual page 117

The installation information given in this text is to be used as a
guide only. WESTERBEKE cannot be responsible in any way for muffler
installations. WESTERBEKE presumes the installer to have a basic
knowledge of marine installation requirements.
Use as few right angle fittings as possible. The use of wire rein-
forced hose is recommended and the hose should be routed to produce
the bends needed.
The use of 90 degree and 45 degree fittings contribute to the rise of
engine exhaust back pressure. (Refer to the Unit Technical Manual for
back pressure specifications.)
The exhaust hose diameters shown are minimums. Exhaust hose diameter
for the discharge hose will have to be incresed if the length of run
from the Hydro-Hush Muffler to the thru-hull discharge is excessive
(25 - 30 feet depending on the number of bends).
CAUTION
THE SEA WATER PUMP WILL CONTINUE TO FILL THE
EXHAUST SYSTEM WITH SEA WATER DURING CRANKING. THE
ENGINE EXHAUST PRESSURE DURING CRANKING MAY NOT BE
STRONG ENOUGH TO EXPEL THE WATER FROM THE MUFFLER
AND PREVENT THE SYSTEM FROM FILLING UP WITH SEA
WATER AND ENTERING THE EXHAUST MANIFOLD AND
CYLINDERS.
IF ENGINE CRANKING EXCEEDS 30 40 SECONDS
APPROXIMATELY, CLOSE THE SEA WATER THRU-HULL AND
OPEN IT IMMEDIATELY AFTER THE ENGINE STARTS.
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