Thor Motor Coach 2009 Mandalay, Owner'S Manual

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MANDALAY
Sulfuric acid in the batteries can cause severe injury or death. Sulfuric acid can cause
permanent damage to eyes, burn skin and eat holes in clothing. Always wear
splash-proof safety goggles and gloves when working around the battery. If battery
electrolyte solution is splashed in the eyes or on the skin, immediately flush with clean
water for 15 minutes. In case of eye contact, seek immediate medical treatment.
Never add acid to a battery once the battery has been placed in service. Doing so may
result in hazardous splattering of electrolyte solution.
Checking the condition of a battery at regular intervals is very important and will help insure its
proper operation. Here are some recommendations for checking and servicing batteries.
1. Keep the battery mounted securely. Vibration causes early failure of many batteries.
2. Check the electrolyte level of the auxiliary batteries at regular intervals. Keep each cell
filled to just above the plates with distilled water. Once the plates have dried out, they
cannot be reactivated, and the capacity of the battery is reduced in direct proportion to
the area of plate surface that has become dry. This kind of damage can occur quickly;
usually it can happen overnight. If the fluid level is low, simply add distilled water.
NOTE : These instructions only apply to batteries other than maintenance-free batteries.
Do not open or break seals on maintenance-free batteries.
• While holding a clean hydrometer vertically and wearing splash-proof safety glasses,
squeeze the rubber bulb, insert the nozzle into the electrolyte in the cell, and release
the bulb. The electrolyte will be sucked up into the barrel or container allowing the
float to ride freely. Start with the cell that is closest to the POSITIVE (+) terminal.
• Squeeze the rubber bulb to release the electrolyte back into the battery's cell.
• To increase the accuracy of the measurement, repeat this process in the same
cell several times so the float will reach the same temperature as the electrolyte. If
you are measuring a large battery, stratification can occur when the more
concentrated electrolyte settles to the bottom. If you notice a difference in the
readings between the top and bottom of the cell, average the two readings.
• At eye level and with the float steady, read the specific gravity at the point the surface
of the electrolyte crosses the float markings. The specific gravity reading should be
between 1.100 and 1.300.
• Release the electrolyte back into the cell from which it was taken, and record the
reading. Be sure to avoid spillage.
• The hydrometer is calibrated at 80° F. Temperature affects the hydrometer reading.
The higher the electrolyte temperature, the higher the specific gravity reading.
The lower the temperature, the lower the specific gravity reading. Add or subtract
four (4) points for each 10° variance from the 80° F chart. Readings between cells
should not vary more than 50 "points" (0.050).
9-8
ELECTRICAL SYSTEMS
Battery Maintenance