If you have just replaced a battery with a new one and you are sure the battery is full and all you get from the starter is a click then this could mean two things .
1, The battery connections are not clean ,the post on a new battery must be cleaned as these have a protective chemical and must be removed .
If the post and clamps are clean then the solenoid on the starter is most likely bad and needs replacing .
Get a Voltmeter and connect this to the battery and set it to 20volts .
Battery voltage should be 12 + volts then with a second helper try and start the engine
and take note of the voltage on the meter ,
If the voltage drops to below 10 volts then the new battery is bad .
If the voltage hardly drops have the starter tested and repaired or replaced .
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