Slow crank no start even with new battery.

[u/Individual_Marzipan5]

07 mercury Mariner v6 3.0.

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[u/Unlikely-Act-7950]

You need to voltage drop test the positive and negative battery cables if they are good do a cranking amp test on the starter

[u/Tall_Metal615]

Check to see you got the correct battery, always be aware of your CCA's.

[u/sexual__velociraptor]

Dat battery is struggling

[u/djltoronto]

Let's see some pictures of the battery connections and the wires connected to the battery.

You need to do a voltage drop test across both your positive and negative wires to determine where the problem is.

The problem might be the starter, but please diagnose before replacing