4.3. Check of density of cooling liquid

PERFORMANCE ORDER
1. Measure by the areometer the specific weight of cooling liquid.
2. Take temperature to cooling liquid and depending on temperature calculate concentration of antifreeze in cooling liquid.

Ratio between concentration of antifreeze in cooling liquid and specific weight

Temperature of °C cooling liquid and specific weight
Temperature of freezing of °C
Safe working temperature of °C
Concentration of cooling liquid
10
20
30
40
50
1,054
1,050
1,046
1,042
1,036
– 16
– 11
30%
1,063
1,058
1,054
1,049
1,044
– 20
– 15
35%
1,071
1,067
1,062
1,057
1,052
– 25
– 20
40%
1,079
1,074
1,069
1,064
1,058
– 30
– 25
45%
1,087
1,082
1,076
1,070
1,064
– 36
– 31
50%
1,095
1,090
1,084
1,077
10,70
– 42
– 37
55%
1,103
1,098
1,092
1,084
1,076
– 50
– 45
60%

Example

Safe working temperature of -15 °C at the weighed specific weight 1,058 and temperature of cooling liquid of 20 °C
Prevention

If concentration of cooling liquid is lower than 30%, anticorrosive properties of cooling liquid go down. At concentration more than 60% worsen frost resistance of cooling liquid.


The recommended cooling liquid

Antifreeze Content of antifreeze in cooling liquid
Ethylene glycol 50%