Charging deep cycle battery through the alternator?

[Joe58C]

I have a 2004 140 hp johnson 4 stroke and have added a deep cylce battery in addition to a starter battery.. The alternator generates 40 amps.

Is is ok to hook them up in parallel?

Thanks.

Joe

[Solarman]

You should invest in a battery switch to connect both batteries, safest and allows you to switch between batteries if need arises. Just make sure everything is wired correctly.
Most 4 strokes, depend on a fully charged, good battery to run properly.

Good luck. Post back if any questions.