OPERATION AND SERVICE INFORMATION
Page 26
Owner’s Manual and Service Guide
Read all of manual to become thoroughly familiar with this vehicle. Pay particular attention to all Notes, Cautions and Warnings
4. Add or subtract four points (.004) to the reading for
every 10° F (6°C) the electrolyte temperature is
above or below 80° F (27° C). Adjust the reading to
conform with the electrolyte temperature, e.g., if the
reading indicates a specific gravity of 1.250 and the
electrolyte temperature is 90° F (32° C), add four
points (.004) to the 1.250 which gives a corrected
reading of 1.254. Similarly if the temperature was 70°
F (21° C), subtract four points (.004) from the 1.250
to give a corrected reading of 1.246 (Ref. Fig. 35 on
page 26).
5. Test each cell and note the readings (corrected to 80°
F or 27° C). A variation of fifty points between any two
cell readings (example 1.250 - 1.200) indicates a
problem with the low reading cell(s).
As a battery ages the specific gravity of the electrolyte
will decrease at full charge. This is not a reason to
replace the battery, providing all cells are within fifty
points of each other.
Since the hydrometer test is in response to a vehicle
exhibiting a performance problem, the vehicle should be
recharged and the test repeated. If the results indicate a
weak cell, the battery or batteries should be removed
and replaced with a good battery of the same brand, type
and approximate age.
Fig. 35 Hydrometer Temperature Correction
160 71.1 +.032
+.030
150 65.6 +.028
+.026
140 60.0 +.024
+.022
130 54.4 +.020
+.018
120 48,9 +.016
+.014
110 43.3 +.012
+.010
100 37.8 +.008
+.006
90 32.2 +.004
+.002
80 26.7 0
–.002
70 21.1 –.004
–.006
60 15.6 –.008
–.010
50 10 –.012
–.014
40 4.4 –.016
–.018
30 –1.1 –.020
–.022
20 –6.7 –.024
–.026
10 –12.12 –.028
EXAMPLE #1:
Electrolyte Temperature
Above 80°F (27°C)
Electrolyte temperature
90° F (32° C)
Hydrometer reading 1.250
1.250 + .004 = 1.254
corrected specific gravity
EXAMPLE #2:
Electrolyte Temperature
Below 80°F (27 °C)
Electrolyte temperature
70° F (21° C)
Hydrometer reading 1.250
1.250 - .004 = 1.246
corrected specific gravity
° F ° C
Electrolyte
Temperature
ef Htc 1