Automatic Transmission Oil Cooler; Coolant Recovery System (Crs); Coolant; Cooling System - Chrysler 1998 Voyager Service Manual

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GENERAL INFORMATION (Continued)

COOLANT RECOVERY SYSTEM (CRS)

This system works with the radiator pressure cap
to use thermal expansion and contraction of the cool-
ant to keep the coolant free of trapped air. Provides a
convenient and safe method for checking coolant
level and adjusting level at atmospheric pressure
without removing the radiator pressure cap. It also
provides some reserve coolant to cover deaeration
and evaporation or boiling losses. All vehicles are
equipped with this system and take various shapes
and forms. (Fig. 3) shows a typical system in the typ-
ical location.
Fig. 3 Coolant Recovery System
See Coolant Level Service, and Deaeration, and
Pressure Cap sections for operation and service.
AUTOMATIC TRANSMISSION OIL COOLER—2.4L
Oil cooler is internal oil to coolant type, mounted
in the radiator left tank (Fig. 4). Rubber oil lines feed
the oil cooler and the automatic transmission. Use
only approved transmission oil cooler hose. Since
these are molded to fit space available, molded hoses
are recommended.

ENGINE THERMOSTAT

The engine cooling thermostats are a wax pellet
driven, reverse poppet choke type. They are designed
to provide the fastest warm up possible by prevent-
ing leakage through them and to guarantee a mini-
mum engine operating temperature of 88 to 93°C
(192 to 199°F). They also automatically reach wide
open so they do not restrict flow to the radiator as
temperature of the coolant rises in hot weather to
around 104°C (220°F). Above this temperature the
coolant temperature is controlled by the fan, the
radiator, and the ambient temperature, not the ther-
mostat.
Fig. 4 Automatic Transmission Oil Cooler

WATER PUMPS

A quick test to tell whether the pump is working is
to see if the heater warms properly. A defective pump
can not circulate heated coolant through the long
heater hose. The water pump on all models can
be replaced without discharging the air condi-
tioning system.

COOLANT

The cooling system is designed around the coolant.
The coolant must accept heat from engine metal, in
the cylinder head area near the exhaust valves. Cool-
ant then carries this heat to the radiator, where the
tube/fin assemblies of these components can give it
up to the air.
The use of aluminum cylinder heads, intake mani-
folds, and water pumps requires special corrosion
protection. Mopar Antifreeze or the equivalent is
recommended for best engine cooling without corro-
sion, when mixed only to a freeze point of -37°C
(-35°F) to -59°C (-50°F). If it loses color or becomes
contaminated, drain, flush, and replace with fresh
properly mixed solution.
CAUTION: Do not use well water, or suspect water
supply in cooling system. A 50/50 ethylene glycol
and distilled water mix is recommended.

RADIATOR

The radiators are cross-flow types (horizontal
tubes) with design features that provide greater
strength along with sufficient heat transfer capabili-

COOLING SYSTEM

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