Geely EC718, EC718RV, EC715, EC715RV. Manual part — 129

2.7.3 System Working Principle
2.7.3.1 System Working Principle

Inside the three-way catalytic converter, the ceramic substrate
exposed to emissions is coated with a catalyst. Catalysts
containing platinum, palladium and rhodium, three kinds of
precious metals. These catalysts promote chemical reactions.

Catalyst is to accelerate the chemical reaction while remain
unchanged itself. Engine exhaust contains carbon monoxide
(CO), hydrocarbons (HC) and nitrogen oxides (NO

X

). When the

exhaust gas flows through the ceramic substrate, the chemical
reactions in the three-way catalytic converter occur. Carbon
monoxide and hydrocarbons is oxidized by the oxygen in the
exhaust gas (O

2

) and turned into carbon dioxide (CO

2

) and

water vapor (H

2

O). Nitrogen oxides and carbon monoxide

through the reduction reaction, was converted into nitrogen
(N

2

). This three-way catalytic converter is called three-way

type, because it turns the three components (CO, HC and
NO

X

) into harmless neutral gas at the same time.

Engine

Exhaust System JL4G18-D

2-431

2.7.4 Component Locator
2.7.4.1 Exhaust

1

2

3

4

FE02-2030b

Legend

1. Exhaust Manifold
2. Three-Way Catalytic Converter Assembly
3. Front Muffler

4. Rear Muffler

2-432

Exhaust System JL4G18-D

Engine

2.7.4.2

Three-Way

Catalytic

Converter

Assembly

1

2

3

4

FE02-2031b

Legend

1. Pre-Catalytic Oxygen Sensor Mounting Hole
2. Three-Way Catalytic Converter Assembly
3. Post-Catalytic Oxygen Sensor Mounting Hole

4. Immunity Section

Engine

Exhaust System JL4G18-D

2-433

2.7.4.3 Front Muffler Assembly

FE02-2032b

2-434

Exhaust System JL4G18-D

Engine