What Batteries do I need for...

[Hornet_UK]

Ok, time has come to replace the batteries on Serendipity so I need some advice on what type I need please folks.

The engine I have is a Yanmar 2GM20. What would be the CCA amount required for this?

I also have a windlass that appears to be connected to a dedicated battery.
So what type of battery should I use for that?

Ideally I'd like to have two batteries in parallel for use of both windlass and leisure use.

 

[Tranona]

For both applications you need a start type battery just the same as you would use in a diesel car. Typically around 75 -80ah. Starter batteries on boats have an easy life if you engine is in good nick and you have an effecient split charging system so that the battery is immediately recharged after you start up and before you charge your house bank.

 

[vyv_cox]

The CCA for 1, 2 and 3 cylinder Yanmars is 200A. My starter battery on a 3GM30 is a Red Flash 900, which starts it but has little reserve. The battery is only rated at 13 Ah and is really somewhat low in capacity, but it fits into the tunnel alongside the gearbox. Provided you have the space I suggest you do as Tranona suggests.

 

[VicS]

The CCA for 1, 2 and 3 cylinder Yanmars is 200A. My starter battery on a 3GM30 is a Red Flash 900, which starts it but has little reserve. The battery is only rated at 13 Ah and is really somewhat low in capacity, but it fits into the tunnel alongside the gearbox. Provided you have the space I suggest you do as Tranona suggests.

The RF 900 is a bit low on its CCA rating as well. Its only 150 amps according to DMS technologies http://www.dmstech.co.uk/pdfs/battery_redflash_hr_01.pdf

I guess the figure you will find elsewhere of 420 amps is really the MCA rating but it is what really counts in your boat.