Motor: 2002 Mercury 175 EFI OT566138
From what I gather I can use an AGM battery for starting this motor, it does have a serpentine belt at top of motor. Correct?
The reason I am changing batteries is when I start my motor all my sonars turn off, I have a small lowrance unit that shows battery voltage and when I crank the engine it drops to 10.0 volts. Also while the motor starts fine it doesn't turn over "snappy" if that makes sense. The battery I have was for my last motor, a Merc 115 elpto and is a marine starting from Advance Auto (#M24-3 AutoCraft) and is a group 24 has 800 CCA, 1000 MCA and a 135 minute reserve.
I really would like to use an AGM in a group 31 size from Sears since they are close to my house, but I will go with whatever is the best bang for the buck. Also a lighter weight battery would really be nice due to the fact that my nitro has a big booty...weight wise