Paccar Peterbilt 320, Operator'S Manual

Page: 171 / 212

PART 8: MAINTENANCE AND SERVICE Engine Cooling System
Desired
ELC/
Water
ratio:
0% 10% 15% 20% 25% 30% 35% 40% 45% 50% 55% 60% 65% 70% 75% 80% 85% 90% 100%
Freeze
point °F
(°C)
+32
(0)
+25
(-4)
+20
(-7)
+15
(-9)
+10
(-12)
+5
(-15)
-5
(-21)
-12
(-24)
-23
(-31)
-34
(-37)
-50
(-46)
-65
(-54)
-75
(-59)
-84
(-64)
-70
(-57)
-55
(-48)
-43
(-42)
-30
(-34)
-5
(-21)
What To Check In An ELC- fi lled Cooling System
ELC Concentration
Check the level of freeze/boilover protection, which is de-
termined by the ELC concentration. Use a glycol refrac-
tometer to determine glycol level. Add ELC to obtain the
ELC to water ratio required to provide the protection you
need. Use the chart below to help determine how much
ELC you need to add.
NOTE: Maximum recommended ELC concentra-
tion is 60% ELC and 40% water by volume (a 60/
40 coolant mixture). The minimum recommended
concentration is 40%.
In an ELC- fi lled cooling system, the freeze point should be
maintained between -30° F and -45° F (-34° C and -43° C)
ELC Condition (Contamination and Inhibitor
Concentration)
Perform a visual inspection of the ELC. It should have no
cloudiness or
fl oating debris. Determine the chemical in-
hibitor concentration level by using an ELC-speci fi c test
kit or test strips. Inhibitor concentration level determines
corrosion protection. If you are concerned about possi-
ble coolant quality, contamination, or mechanical problems,
submit a coolant sample for analysis. Improper mainte-
nance may cause coolant degradation and could result in
damage to the cooling system and engine components.
Consult your dealer or the ELC manufacturer’s represen-
tative for recommended ELC test kits, test strips, and lab-
oratory sample procedures.
R(08/07) Y53-6015 – 167 –