03-4
1. DESCRIPTION AND OPERATION
1) Exhaust System
When you are inspecting or replacing exhaust system components, make sure there is adequate
clearance from all points on the underbody to avoid possible
overheating of the floor panel and possible damage to the passenger compartment insulation
and trim materials.
Check the complete exhaust system and the nearby body areas and trunk lid for broken,
damaged, missing or mispositioned parts, open seams, holes, loose connections, or other
deterioration which could permit exhaust fumes to seep into the trunk may be an indication of a
problem in one of these areas. Any defects should be corrected immediately.
2) Catalytic Converter (Gasoline Engine)
When jacking or lifting the vehicle from the body side rails, be certain that the lift pads do not
contact the catalytic converter, as this could damage the catalytic converter.
Use of anything other than unleaded fuel will damage the catalyst in the catalytic converter. 1.
2.
Catalytic Converter Structure ▶
The Catalytic converter of monolith type consists
of 2 walled metal bodies which is made of
Cordierite. The principal element of converter
consists of the materials like Alumina or oxidized
Serume in order to apply to Ceramic Monolith.
Washer coat operates first, and catalytic metal
elements (Pt, Pd, Rh) operates to washer coat
next.
Monolith type is lighter than other types, easy to
manufacture and quickly approaches to proper
temperature. Washer coat is used to make a
contact surface with exhaust gas bigger by
adhering closely to small holes
of inner layer. If a lead compound or phosphorus
adheres to the surface and the temperature rises,
its surface is decreased. The total area of general
monolith converter is about 45, 000~500,000ft3.
(10 times of a football field) Generally
Alumina
(AL2 O3) is used as a raw materialand its 7
phases of gamma, delta, theta have big areas and
high stability for the temperature, and nowadays
gamma Alumina is used usually.
04-6
2. DESCRIPTION AND OPERATION
1) General Description
The cooling system maintains the engine temperature at an efficient level during all engine
operating conditions.
When the engine is cold, the cooling system cools the engine slowly or not at all. This slow
cooling of the engine allows the engine to warm up quickly.
The cooling system includes a radiator and recovery subsystem, cooling fans, a thermostat and
housing, a water pump, and a water pump drive belt. The timing belt drives the water pump.
All components must function properly for the cooling system to operation. The water pump
draws the coolant from the radiator. The coolant then circulates through water jackets in the
engine block, the intake manifold, and the cylinder head. When the coolant reaches the operating
temperature of the thermostat, the thermostat opens. The coolant then goes back to the radiator
where it cools.
This system directs some coolant through the hoses to the heat core. This provides for heating
and defrosting.
The coolant reservoir is connected to the radiator to recover the coolant displaced by expansion
from the high temperatures. The coolant reservoir maintains the correct coolant level.
The cooling system for this vehicle has no radiator cap or filler neck. The coolant is added to the
cooling system through the coolant reservoir.
2) Radiator
This vehicle has a lightweight tube-and-fin aluminum radiator. Plastic tanks are mounted on the
upper and the lower sides of the radiator core.
On vehicles equipped with automatic transaxles, the transaxle fluid cooler lines run through the
radiator tank.
A radiator drain plug is on this radiator.
To drain the cooling system, open the drain plug.
3) Coolant Reservoir
The coolant reservoir is a transparent plastic reservoir, similar to the windshield washer reservoir.
The coolant reservoir is connected to the radiator by a hose and to the engine cooling system by
another hose.
As the vehicle is driven, the engine coolant heats and expands. The portion of the engine coolant
displaced by this expansion flows from the radiator and the engine into the coolant reservoir. The
air trapped in the radiator and the engine is degassed into the coolant reservoir.
When the engine stops, the engine coolant cools and contracts. The displaced engine coolant is
then drawn back into the radiator and the engine. This keeps the radiator filled with the coolant to
the desired level at all times and increases the cooling efficiency.
Maintain the coolant level between the MIN and MAX marks on the coolant reservoir when the
system is cold.