Suitability of these batteries on our boat??

[PaulGooch]

That is a theoretical maximum - and you are unlikely to achieve it - and unless you have some clever electronics fitted it will drop off quite rapidly.
You may also find that only one engine charges the domestic batteries.
You still need to do a bit of investigation I think.

Posted while i was typing, must type faster

 

[VicS]

Quoting myself now... LOL....

Son has just found the answer. The AD31 engines will replace 50 amp per hour per engine.

So with 430 Ah total battery power it would take approx 4.3 hours to recharge from flat. Bearing in mind they wouldn't be run enough to go flat this shouldn't be a problem.

So now I have that bit of info does it mean the batteries are appropriate?

May be sounding a bit thick here, but just want to make sure it is possible before spending out..

You mean the max output of the alternators is 50 amps each

Although in practice you may get that initially the actual current will fall to a lower figure tailing off as the batteries recharge.
Watch the ammeters next time you are recharging with the engines to get some idea what happens in reality.

 

[HONEYMOMMY]

Thanks to everyone for all your advice and expertise.

This has given hubby and son clear advise as to what they need to find out before making the decision as to the best option.

A little more research...