Technical data

13773-001
24-30
Page 1330 Nov 2000
Note: The battery should be removed from the airplane prior to inspection. The battery
box should be washed out thoroughly and dried each time the battery is removed.
The battery vent hose should be inspected periodically for any damage, kinks or
obstructions. If adding distilled water in freezing weather, charge battery long
enough to mix electrolyte and water. Never use a wire brush to clean the battery;
instead use a brush with non-conductive bristles.
(a) Acquire necessary tools and equipment.
(b) Remove the battery. (Refer to 24-30)
CAUTION: To prevent contamination from one cell to the other, immediately reinstall
cell caps into their original location after testing the specific gravity.
(c) Remove the battery cell covers and check the specific gravity of each cell. The electrolyte
should have a specific gravity of 1.225 or above to avoid freezing. If the level is too low for
accurate hydrometer readings, add just enough distilled water to cover the plates and
charge the battery to mix the electrolyte. Continue charging until the voltage and specific
gravity readings are constant over three readings taken at 1/2 hour intervals.
Note: Adjust the level of electrolyte at the end of the charge, because the level will
rise from acid coming back into the electrolyte mix, normal gassing, and
expansion from the temperature rise. When adding distilled water to the
battery, the electrolyte should just touch or be slightly short of the eyelet
(level indicator) when the battery is warm and in a good state of charge. As
an example, this condition would exist just after a bench charge or when the
aircraft has just returned from a flight of ninety minutes or more.
Description P/N or Spec. Supplier Purpose
Hydrometer - Any Source Measure specific gravity
Acid Resistant Brush
(Nonmetallic)
- Any Source Remove corrosion
Petroleum Jelly (W-P-236) Any Source Retard corrosion
Cotton cloth (clean and
lint free)
- Any Source Wipe components clean
Distilled Water - Any Source Replenish battery fluid level
Small Plastic Syringe - Any Source Add fluid to battery cells
Bicarbonate Of Soda
(Baking Soda)
- Any Source Neutralize Electrolyte
Rubber Apron And Gloves - Any Source Prevent Electrolyte Exposure
Face Shield And Goggles - Any Source Prevent Electrolyte Exposure