Westerbeke 3.5 SBCG Operator's Manual page 8

CARBON MONOXIDE "CO"/ LOW-CO GENERATORS
IMPORTANT INFORMATION
DESCRIPTION
Carbon monoxide "CO" is a component of engine eXhaust.
It
is a colorless, tasteless, odorless, lighter
than
air poisonous
gas that can kill you without any warning. CO poisoning is
one of the major safety risks associated with boating. It is a
threat that must not be underestimated.
Westerbeke Low-CO generators are designed to reduce
normal levels of CO in the engine exhaust by approximately
99%.
Several standards for CO have been published, expressed in
parts per million "ppm" and hours of exposure:
Regulator CO ppm Exposure Hours
EPA
9 8
ACGffi.
25
8
EPA
35 1
NIOSH
35
8
OSHA 50 8
ACGffi
125 0.5
NIOSH
200 0.0
NIOSH
1200 0.0
(IDLH)
1200 ppm is the so-called IDLH concentration·
IMMEDIATELY DANGEROUS TO LIFE AND HEALTH.
A city in California characterizes the effect of CO
concentration this way:
Parts per Million
Responses
25 Permissible exposure level, no
apparent toxic symptoms.
100
No poisoning for long period.
Allowable for several hours.
200
Should not be exposed above
this
level for any period of
time. A possible mild frontal
headache in two
to
three hours.
Even though the generator normally produces very low levels
Westerbeke Low-CO generators are designed to reduce
normal levels of CO in the engine exhaust by approximately
99%., an exhaust leak of untreated exhaust would be
extremely dangerous. For this reason it is extremely
important to install a CO detector near the generator and to
be sure it is always turned on and functioning properly. If this
detector sounds, do not tum it off, assuming it is a false
signal. You can not taste, smell, or otherwise detect CO.
Leave the detector on, tum off all engines and generators,
evacuate the boat leaving ports and hatches open, and seek
professional help.
As soon as CO leaves the exhaust outlet, the level is subject
to dilution in the open air. The closer a person is to the
exhaust outlet, the higher the concentration of CO.
In a closed space, such as the engine compartment, the boat,
or underneath a stem swim platform, concentrations will
potentially rise to the undiluted level emanating from the
exhaust system due to a lack of fresh air to dilute the exhaust
gas. Therefore, one should never rely on dilution of the
eXhaust to provide a margin of safety.
Westerbeke Low-CO generators achieve an approximate
99% reduction of typical CO by precise control control of the
engine's air/fuel ration coupled with after treatment in a
special catalyst. CO emissions are not the same for every
model because each engine is different. Also, certain fuel
system components are commonized aeross several engine
models being adequate for some and extra-adequate for
others, thus producing different CO levels for different
models.
The fuel system which accomplishes the required precise
air/fuel ratio control is comprised of many different
components: purchased sub-assemblies, machined castings,
sensors, electronics and others. Because of the extreme level
of CO reduction, any variability in the functioning of any
these components can and will cause variability of the CO
output.
CO concentration also varies with load. Usually, but not
always, the worst case CO concentration occurs
at
maximum
load.
IV
INSPECTION
The catalyst is critical to optimizing CO levels. Any water
intrusion into the engine's exhaust system will likely quickly
compromise the proper operation of the catalyst.
Westerbeke's exhaust system installation instructions
dated June 2016 Revision 4 must be adhered to.
NOTE:
Water intrusion is not a product defect
and
is not
covered under warranty, neither Westerbeke
s
normal
product warranty nor the emissions specific warranty
mandated by various regulating authorities such as EPA
andCARB.
Maintenance of any components affecting the flow of air into
the engine or the flow of fuel to the engine is critically
important. Fuel filters, air filters, flame arrester screens
MUST be properly maintained.
Inspection of the catalyst at the prescribed intervals is
critically important. The exhaust elbow is removed by
loosening the metal clamp to provide a view of the output
surface of the catalyst. Any visual irregularity of the nonnal
flush, honeycomb appearance is most likely a result of water
intrusion. The cause of the irregularity must be identified and
addressed. If there is irregularity, the catalyst and sealing
gasket must be replaced. The water injected exhaust elbow
casting must be inspected also for corrosion and replaced as
needed. Upon careful reassembly of the catalyst, new sealing
gasket, and exhaust elbow, check for the presence of CO
while the engine is running. This must be performed with a
CO analyzer.