ME420STI Battery Power

[georgeirl]

Folks,

Anyone know of the top of their heads the recommended aH rating for the cranking battery for this motor?

George

[Brian]

I've got an ME432 and I use 110ah (2 of), one for consumer stuff and one for starting the engine.
Don't know if this helps?
Last time I bought a new battery (if that is your question) it cost circa £180.

[georgeirl]

Brian -- its was the 110ah part i was looking for!

Thanks.

[paulbrown22]

Likewise, I have a Yanmar 6LP (same base block), and run 2 x 110ah batteries.

[georgeirl]

guys can you clarify the options below for me?

1) both batteries used in cranking
2) one for engine, one for accessories.

its option 2 i have had in other boats (and what i was planning here) but those of you who run these if you could clarify it would be great.

George

P.S for reference i just picked up a 120ah batter with a CCA of 900 amps

[paulbrown22]

I have option 2, with a key to enable linking the two batteries for cranking should you ever need to.

[Brian]

Yup, I have the same arrangement as paulbrown22.
This seems to be the preferred arrangement as:
-I have had the consumer battery die, as it had been for months on a marina berth and had totally discharged when the auto-pump engaged. Nevertheless I was able to start the engine with the "main" battery and recharge the consumer on along run up the the Scottish Isles.
-Conversely I can start the engine from the consumer when the main one fails. That also recharges itself on a long run.
Takes about 5 hours of running before it totally recharges.