Subaru XT 1988 Service Manual page 72

PERIODIC MAINTENANCE SERVICES
1-5
13) After adding coolant, securely install radiator and reserve
PROCEDURE TO ADJUST THE
tank caps.
CONCENTRATION OF THE COOLANT
RELATIONSHIP OF SUBARU COOLANT
CONCENTRATION AND FREEZING
TEMPERATURE
The concentration and safe operating temerature of the
SUBARU coolant is shown in the following diagram. Measur-
To adjust the concentration of the coolant according to
temperature, find the proper fluid concentration in the above
diagram and replace the necessary amount of coolant with an
undiluted solution of SUBARU genuine coolant (concentra-
tion 50%).
The amount of coolant that should be replaced can be deter-
mined using the following diagram,
ing the temperature and specific gravity of the coolant will
(1) Except XT6
provide this information.
1.100
1.090
1.080
~
1.070
'0
o
.:: 1.060
o
Safe operating temperature
>
(1.049)
'~1.050
- - - - - - - -
e
CI
,S!
1.040
}1.030
1.020
1.010
1.000
'---~-~~--1:--..L----::!01.--"'1:-'::0~--'20---'~3:'::0---'401.--5~0~.....I1
Fig. 18
[Example]
(32) (50) (68) (86) (104) (122)
Coolant temperature
°c
(OF)
L1479
If the coolant temperature is 25°C (77°F) and its specific
gravity is 1.049, the concentration is 35% (point A), the safe
operating temperature is -14°C (7°F) (point Bl. and the
freezing temperature is -20°C (-4°F) (point C).
13
c-
5
.§
(5,3,4.4)
~
4
2
(4,2,3.5)
"C
~
3
.§
(3.2,2.6)
"C
III
.c
o 2
E
(2,1,1.8)
co
'0
o
t)
1
'0
(1,1.0,9)
>
...
';;
Necessary concentration of coolant
r -_ _ _
~ O~--~r-~~~~~~-L~~~--r
::J
o
10 20 30 40
50
Concentration of coolant in the vehicle cooling system %
Concentration of coolant in vehicle and quantity to be drained L2-049
Fig. 19
[Example]
Assume that the coolant concentration must be increased from
30% to 40%. Find point A, where the 30% line of coolant
concentration intersects with the 40% curve of the necessary
coolant concentration, and read the scale on the vertical axis
of the graph at height A. The quantity of coolant to be
drained is 2.5 liters (2.6 US qt, 2,2 Imp qt). Drain 2,5 liters
(2.6 US qt, 2,2 Imp qt) of coolant from the cooling system
and add 2.5 liters (2.6 US qt, 2.2 Imp qt) of the undiluted
solution of SUBARU coolant.
If a coolant concentration of 50% is needed, drain all the
coolant and refill with the undiluted solution only.