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12 Volt Lawn Mower Battery – How to Change

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Cordless lawn mowers that utilize a 12-volt battery can lose its power during operation or in instances that they are not used often.

The battery fails to turn on the starting motor of the engine and usually, if the battery is rechargeable, it must be charged from a subsidiary source.

This may come from a battery charger. The charger's front has the label that will identify the types of batteries that can be charged with it. Refer to the manual of battery charger if it's compatible with your battery's model.

Step 1:

Move out the battery from the lawn mower. Correct size of end wrenches must be used in pulling the cable connectors out of the top part of the battery.

First, take out the negative cable. Put a loose cable so that it will not touch or come in contact with the negative post.

Take out the positive connector. This will see to it that if this cable accidentally came in contact with the metal part of the land mower, no electric short circuit will occur. Otherwise, a permanent damage on the battery will be generated if electrical short will happen.

Step 2:

The battery must be placed on a solid and secure surface like a table or a workbench. Enough ventilation is needed if charging a battery because during charging operation, highly flammable and explosive gasses can be emitted.

Step 3:

Pay attention on the details of the battery charger on the instruction manual on the front of the charging unit. Most charger units have dual voltage selection on charging cycle, 12 volts and 6 volts.

Make sure that the battery charger is shifted on the 12-volt setting operation. Correct charging ampere must be selected in corresponding to the size of your battery. Commonly, 3-6 ampere is sufficient charging rate.

Step 4:

The red charging cable must be connected to the positive (+) terminal of the battery. Then, the black charging cable must be connected to the negative (-) terminal. Joggle both the connectors to assure a tight connection so that they will not become loose during the entire charging process.

Step 5:

For the last time, check the connections and the selector switches. It is advisable to double check than to operate the battery charger blindly.

Plug the charger unit into the wall outlet. Take a look at the charging meter located on the face of the charging unit. It should have the same reading of amperage that what has the charging rate has set for.

Step 6:

Run the charger up to a time that the charging meter reads 0 amperes. This indicates that the battery is now fully charged.

Step 7:

Unplug the charger unit from the outlet.

After which, take out the connectors. Put back the battery into the lawn mower.

First, connect the positive battery terminal, then followed by the negative connector of the battery.