heating and cooling DODGE RAM 1500 1998 2.G Service Manual

(8) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
Use only the specified O-ring as it is made of a spe-
cial material for the R-134a system. Use only refrig-
erant oil of the type recommended for the A/C
compressor in the vehicle.
(9) Connect the liquid line to the condenser outlet
port.
(10) Install and tighten the nut that secures the
liquid line fitting to the condenser. Tighten the nut to
20 N´m (180 in. lbs.).
(11) Install the plastic cover onto the condenser
outlet stud.
(12) Remove the tape or plugs from the suction
line fitting and condenser inlet port.
(13) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the suction line fit-
ting. Use only the specified O-ring as it is made of a
special material for the R-134a system. Use only
refrigerant oil of the type recommended for the A/C
compressor in the vehicle.
(14) Connect the suction line to the condenser inlet
port.
(15) Install and tighten the nut that secures the
suction line fitting to the condenser. Tighten the nut
to 20 N´m (180 in. lbs.).
(16) Reconnect the battery negative cable.
(17) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE).(18) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM CHARGE).
A/C DISCHARGE LINE
DESCRIPTION
The A/C discharge line is the refrigerant line that
goes from the A/C compressor to the A/C condenser.
The A/C discharge line for the 5.9L Diesel engine is
serviced as an assembly with the suction line. The
A/C discharge line has no serviceable parts except
the rubber O-ring seals.
CAUTION: Use only O-ring seals specified for the
vehicle. Failure to use correct O-ring seal will cause
the refrigerant system connection to leak.
The O-ring seals used on the connections are made
from a special type of rubber not affected by R-134a
refrigerant. The O-ring seals must be replaced when-
ever the A/C discharge line is removed and installed.
If the A/C discharge line is found to be leaking or
is damaged, it must be replaced.
REMOVAL
REMOVAL - 5.9L DIESEL ENGINE
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
WARNING) and (Refer to 24 - HEATING & AIR CON-
DITIONING/PLUMBING - CAUTION).
(1) Disconnect and isolate the battery negative
cable.
(2) Recover the refrigerant from the refrigerant
system (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - STANDARD PROCEDURE -
REFRIGERANT RECOVERY).
(3) Disconnect the wire harness connector from the
A/C pressure transducer.
(4) Remove the nut that secures the discharge line
fitting to the condenser inlet port (Fig. 15).
(5) Disconnect the discharge line from the con-
denser.
(6) Remove the O-ring seal from the discharge line
fitting and discard.
(7) Install plugs in, or tape over the discharge line
fitting and condenser inlet port.
(8) Remove the bolt that secures the suction/dis-
charge line assembly to the A/C compressor.
Fig. 14 Condenser/Cooling Fan Assembly
1 - LH MOUNTING BOLT
2 - FRONT UPPER CROSSMEMBER
3 - LOWER MOUNTING FLANGE
4 - UPPER MOUNTING SCREW (2)
5 - LOWER MOUNTING SCREW (2)
6 - MOUNTING TABS
7 - CONDENSER COOLING FAN MOTOR
8 - COOLING FAN WIRE CONNECTOR
9 - RH MOUNTING BOLT
24 - 56 PLUMBINGDR
A/C CONDENSER FAN (Continued)

HEATER INLET HOSE
REMOVAL
The heater inlet hose is constructed from rubber
hoses and plastic hose connectors. The ends are
secured to the heater core, engine and engine coolant
reservoir (depending on engine application) by spring
tension clamps.
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
WARNING) and (Refer to 24 - HEATING & AIR CON-
DITIONING/PLUMBING - CAUTION).
(1) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(2) Remove the heater hose retaining brackets as
required (depending on engine application).
(3) Using spring tension clamp pliers, compress
and slide the clamps off of each end of the hose being
removed (Fig. 24).
CAUTION: DO NOT apply excessive pressure on
heater tubes or connections when removing heater
hoses. Excessive pressure may damage or deform
the tubes/heater core, causing an engine coolant
leak.
(4) Disconnect each hose end by carefully twisting
the hose back and forth on the tube, while gently
pulling it away from the end of the tube.
(5) If necessary, carefully cut the hose end and
peel the hose off of the tube.
NOTE: Replacement of the heater inlet hose will be
required if the hose ends are cut for removal.
(6) Remove the heater inlet hose from the engine
compartment.
(7) Separate the heater hoses from each other as
required (depending on engine application).
INSTALLATION
(1) If separated, reconnect the heater hoses to each
other as required (depending on engine application).
(2) Position the heater inlet hose into the engine
compartment.
(3) Using spring tension clamp pliers, compress
and slide each clamp away from the end of the hose
being installed.
(4) Install each hose by carefully twisting the hose
back and forth while gently pushing it onto the tube
end.(5) Using spring tension clamp pliers, compress
and slide the clamps onto each end of the hose being
installed.
(6) Install the heater hose retaining brackets as
required (depending on engine application).
(7) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
HEATER RETURN HOSE
REMOVAL
The heater return hose is constructed from rubber
hoses and plastic hose connectors. The ends are
secured to the heater core, engine and engine coolant
reservoir (depending on engine application) by spring
tension clamps.
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
WARNING) and (Refer to 24 - HEATING & AIR CON-
DITIONING/PLUMBING - CAUTION).
Fig. 24 Heater Hoses - Typical
1 - HEATER CORE TUBES
2 - HEATER INLET HOSE
3 - RETAINING BRACKET
4 - HOSE CONNECTOR
5 - SPRING CLAMP
6 - HEATER RETURN HOSE
24 - 64 PLUMBINGDR

(1) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(2) Remove the heater hose retaining brackets as
required (depending on engine application).
(3) Using spring tension clamp pliers, compress
and slide the clamps off of each end of the hose being
removed (Fig. 25).
CAUTION: DO NOT apply excessive pressure on
heater tubes or connections when removing heater
hoses. Excessive pressure may damage or deform
the tubes/heater core, causing an engine coolant
leak.
(4) Disconnect each hose end by carefully twisting
the hose back and forth on the tube, while gently
pulling it away from the end of the tube.
(5) If necessary, carefully cut the hose end and
peel the hose off of the tube.
NOTE: Replacement of the heater return hose will
be required if the hose ends are cut for removal.
(6) Remove the heater return hose from the engine
compartment.
(7) Separate the heater hoses from each other as
required (depending on engine application).INSTALLATION
(1) If separated, reconnect the heater hoses to each
other as required (depending on engine application).
(2) Position the heater return hose into the engine
compartment.
(3) Using spring tension clamp pliers, compress
and slide each clamp away from the end of the hose
being installed.
(4) Install each hose by carefully twisting the hose
back and forth while gently pushing it onto the tube
end.
(5) Using spring tension clamp pliers, compress
and slide the clamps onto each end of the hose being
installed.
(6) Install the heater hose retaining brackets as
required (depending on engine application).
(7) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE).
LIQUID LINE
DESCRIPTION
The liquid line is the refrigerant line that carries
refrigerant from the A/C condenser to the evaporator.
The liquid line for this model consist of two separate
lines that connect to each other. The liquid lines are
made from light-weight aluminum or steel, and use
braze-less fittings.
The front half of the liquid line contains the fixed
orifice tube. The liquid lines are only serviced as an
assembly, except for the rubber O-ring seals used on
the end fittings. The liquid lines cannot be adjusted
or repaired and, if found to be leaking or damaged,
they must be replaced.
REMOVAL
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
WARNING) and (Refer to 24 - HEATING & AIR CON-
DITIONING/PLUMBING - CAUTION).
(1) Disconnect and isolate the battery negative
cable.
(2) If equipped with the diesel engine, remove the
passenger side battery (Refer to 8 - ELECTRICAL/
BATTERY SYSTEM/BATTERY - REMOVAL).
(3) If equipped with the diesel engine, remove the
passenger side battery tray (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/TRAY - REMOVAL).
(4) Recover the refrigerant from the refrigerant
system (Refer to 24 - HEATING & AIR CONDITION-
Fig. 25 Heater Hoses - Typical
1 - HEATER CORE TUBES
2 - HEATER INLET HOSE
3 - RETAINING BRACKET
4 - HOSE CONNECTOR
5 - SPRING CLAMP
6 - HEATER RETURN HOSE
DRPLUMBING 24 - 65
HEATER RETURN HOSE (Continued)

designs. Useonlyrefrigerant oil of the same type as
recommended to service the refrigerant system
(always refer to the specification tagincluded
with the replacement A/C compressor or the under-
hood A/C system specification tag).
OPERATION
After performing any refrigerant recovery or recy-
cling operation, always replenish the refrigerant sys-
tem with the same amount of the recommended
refrigerant oil as was removed. Too little refrigerant
oil can cause compressor damage, and too much can
reduce air conditioning system performance.
PAG refrigerant oil is much more hygroscopic than
mineral oil, and will absorb any moisture it comes
into contact with, even moisture in the air. The PAG
oil container should always be kept tightly capped
until it is ready to be used. After use, recap the oil
container immediately to prevent moisture contami-
nation.
STANDARD PROCEDURE - REFRIGERANT OIL
LEVEL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
WARNING) and (Refer to 24 - HEATING & AIR CON-
DITIONING/PLUMBING - CAUTION).
CAUTION: The refrigerant oil in the R-134a A/C sys-
tem is unique depending on the A/C compressor
used. Use only PAG oils that are designed to work
with R-134a refrigerant and the A/C compressor in
the vehicle. Always refer to the underhood A/C Sys-
tem Specification Label for the correct oil designa-
tion.
It is important to have the correct amount of lubri-
cant in the A/C refrigerant system to ensure proper
lubrication of the A/C compressor. Too little lubricant
will result in damage to the compressor. Too much
lubricant will reduce the cooling capacity of the A/C
system and consequently result in higher discharge
air temperatures.
The lubricant used in the compressor is polyalka-
lene glycol PAG lubricant. Only the refrigerant lubri-
cant approved for use with this vehicle should be
used to service the system. Do not use any other
lubricant. The lubricant container should be kept
tightly capped until it is ready for use. Refrigerant
lubricant will quickly absorb any moisture it comes
in contact with.
It will not be necessary to check the oil level in the
A/C compressor or to add oil, unless there has beenan oil loss. An oil loss may occur due to component
replacement, or a rupture or leak from a refrigerant
line, connector fitting, component or component seal.
If a leak occurs, add 30 milliliters (1 fluid ounce) of
the recommended refrigerant oil to the refrigerant
system after the repair has been made. Refrigerant
oil loss will be evident at the leak point by the pres-
ence of a wet, shiny surface around the leak.
COMPONENT REFRIGERANT OIL LEVEL CHECK
When an air conditioning system is first assembled
at the factory, all components (except the A/C com-
pressor) are refrigerant oil free. After the refrigerant
system has been charged with (R-134a) refrigerant
and operated, the oil in the A/C compressor is dis-
persed through the lines and components. The A/C
evaporator, A/C condenser, and accumulator will
retain a significant amount of oil. Refer to the A/C
Component Refrigerant Oil Capacities table. When a
component is replaced, the specified amount of refrig-
erant oil must be added. When a new A/C compressor
is being installed, drain the lubricant from the used
compressor, measure the amount drained and discard
the used lubricant. Drain the lubricant from the new
A/C compressor into a clean container. Return the
amount of lubricant measured from the used com-
pressor, plus the amount reclaimed from the system
back into the new A/C compressor. When a line or
component has ruptured and oil has escaped, the
accumulator must be replaced along with the rup-
tured component.
A/C COMPONENT REFRIGERANT OIL
CAPACITIES
Component ml. oz.
Total System Fill 180 6
Accumulator 60 2
Condenser 30 1
Evaporator 60 2
Compressor Drain and measure
the oil from the old
compressor - see
text.
COMPRESSOR REFRIGERANT OIL LEVEL CHECK
NOTE: Most reclaim/recycling equipment will mea-
sure the lubricant being removed during recovery.
This amount of lubricant should be added back into
the system. Refer to the reclaim/recycling equip-
ment manufacturers instructions.
(1) Recover the refrigerant from the system.
DRPLUMBING 24 - 69
REFRIGERANT OIL (Continued)