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Pete, Electronic Engineer
Category: Marine Electronics
Satisfied Customers: 18127
Experience:  Over 16 years of experience installing and repairing electronics.
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What is a good battery to use with my 2 - 2003 Yamaha 150

Customer Question

What is a good battery to use with my 2 - 2003 Yamaha 150 HPDI Motors
Submitted: 1 year ago.
Category: Marine Electronics
Expert:  Pete replied 1 year ago.

Hi there,

You will need to choose a high spec battery with a large reserve, because at low RPMS (below 1200-1400 RPMS) the engine consumes more power than the charging system puts out, so you will need to be able to power all of the Pumps and ECMS, etc.

Having a large reserve capacity ensures that during typical usage (including trolling, no-wake zones, etc.) you will not have a battery left so weak as to not run the pumps and ECMs, or start the motors.
If you are on a budget then you could use the Deka group 27M. This is a starting battery that has sufficient reserve capacities: