Westerbeke 12B TWO Operator's Manual page 19

Exhaust System Failures
When the engine's sea water is fed into an exhaust system so that the full stream of this water strikes a sur-
face, erosion takes place. This erosion may cause premature failures. The proper design of either a water
jacketed or water injected 'Wet" exhaust system to prevent this problem requires that the sea water inlet be
positioned so that the entering stream of sea water does not directly strike a surface. In addition, the velocity
of the entering sea water stream should be as low as possible, which can be achieved by having inlet fittings
as big in diameter as possible.
The best protection against exhaust system leaks is to routinely inspect the complete exhaust system. Check
for leaks around manifolds, gaskets, and welds. Make sure exhaust lines are not heating surrounding areas
excessively. If excessive heat is present, correct the situation immediately. If you notice a change in the
sound or appearance of the exhaust system, inspect the exhaust system and correct the cause.
Exhaust risers installed off the exhaust manifold should not exceed 8 Ibs in total weight when rigidly con-
nected. Excessive weight and vibration can result in a manifold failure and/or the fracturing of the riser from
the manifold at Its attachment. Dry portions of the exhaust connected to the manifold, which lay before the
water injected exhaust system,
MUST
be properly insulated to retain the exhaust heat within the exhaust pipe
IWARNINGI
Although diesel engine exhaust gases are not as toxic as exhaust fumes from gasoline en-
gines, carbon monoxide is present in diesel exhaust fumes in less concentration. Carbon
monoxide is a dangerous gas that can cause unconsciousness and is potentially lethal. Some
of the symptoms or signs of carbon monoxide inhalation or poisoning are as follows:
o Dizziness o Vomiting
o I ntense Headache o Muscular Twitching
o Weakness and Sleepiness o Throbbing in Temples
If you experience any of the above symptoms, get out into fresh air immediately.
Make sure there are no unnecessary objects suspended from any portion of the exhaust lines. Excessive
weight could cause deflection or distortion of the lines, resulting in damage or leaks. Inspect insulated por-
tions of the exhaust system to ensure there is no deterioration of the insulation.
Oil Drain
An oil sump drain hose is installed on the engine with the discharge end secured by a bracket at the front of
the engine. Oil may be drained from this hose by removing the cap and the discharge end of the hose from
the support bracket and lowering the hose into a container. The hose cap fitting is 1/4 inch NPT (National
Pipe Tap) and can be extended, or have a pump added, for easier removal of the old oil, if desired.
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Westerbeke Diesel Engines