Engines & Controls
3-3
Catalyst Engines
Due to federal and state regulations many newer domestic marine
engines are retrofi tted from the engine manufacturer with a catalytic
converter system for a cleaner environment. The sheer numbers of
these engines will fi ll the marine propulsion market over the next few
years.
Simply stated, a catalytic converter utilizes extreme heat to reduce the
engine’s output of hydrocarbons and carbon monoxide thus reducing
pollutants. The system theory involved follows the automotive market
but the actual parts and closed loop designs are unique to the marine
industry due to temperature, space restrictions, weight and corrosion
factors found in the marine environment.
Both major engine manufacturers incorporate catalytic converters
within a water-jacketed manifold. Oxygen sensors are placed in the
system along with on board monitoring equipment. The systems permit
the engines to operate at normal horsepower ratings.
Read and understand the typical emission monitoring system explained
later in this chapter. Also, read the engine manufacturer’s operation
manual for more detailed information regarding catalytic converters
and system maintenance requirements.
To Next Page
Loading...
