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LP Engine G430(3.0L) LP Fuel System (Low Emission Version)
Catalytic Muffler
The catalytic muffler is mounted in the exhaust gas
stream of G430 engine. The catalytic muffler
facilitates oxidation and reduction reactions that
reduce the amount of unwanted constituents in the
exhaust gas stream. Catalytic mufflers have sound
deadening and spark arresting features
incorporated into the design.
After combustion the contents of the engine
cylinder(s) are expelled into the exhaust system.
These hot gases next travel to the catalytic muffler.
The catalytic muffler is made up of a shell (1)
incorporating an inlet (2) and an outlet (4). Inside,
the catalytic muffler contains a three-way catalyst
section (3) as well as sound dampening and spark
arresting features. The three-way catalyst section
(3) consists of a honeycomb coated with a mixture
of platinum, palladium and rhodium. The hot
exhaust gases enter the catalytic muffler through
the inlet (1). Next the hot exhaust gases flow
through the catalyst section (3) where an oxidation
and reduction reactions take place. These chemical
reactions reduce the amount of CO, HC and NOx in
the engine exhaust. The exhaust gas then flows
through the outlet (4).
Reaction Stage
CO + O
2
= CO
2
Oxidation
HC + O
2
= H
2
O + CO
2
Oxidation
NO
X
+ CO = N
2
+ CO
2
Reduction
NO
X
+ H
2
= N
2
+ H
2
O Reduction
NO
X
+ HC = N
2
+ H
2
O = CO
2
Reduction