Starter battery that won't break the bank

[pedroinlondon]

Mornings

 

The starter battery fitted by the boat builders has probably expired after 6 years.

It's a Dynamo 110 and I left it home charging with a MXS 5.0 charger, but even if that revives it for the next cruise I think it's time it's retired.

Any suggestions on preferably similar sized batteries (11'' distance in between terminals) in the £100 neighbourhood?

It won't need to be a particularly excellent battery as it will be connected to the solar panel system but a decent cold cranking rating would be nice.

Thanks

[rusty69]

I can't help with the sizing, but did notice the battery supplier Tayna batteries is offering 20% off on some of their batteries on ebay, with free shipping. This works out a bit cheaper than buying through their website.

[Jen-in-Wellies]

Does the engine normally start easily? If so, then you can probably safely go for a smaller battery. Cold cranking amps is a better specification to match with the old battery than amp.hour capacity. If going to a smaller battery, then make sure that the battery is held down properly, so it can't move, so it can meet the boat safety scheme requirements. Distance between terminals isn't important. The big red and black wires being able to reach the terminals is! Try a motor factors, or commercial vehicle parts suppliers for getting a new one, if you don't want to mail order.

 

Jen

[dor]

When my starter battery expired recently I replaced it with an ex-domestic battery which has been waiting to go to the scrappie.  Whilst it is well sulphated, it will still hold a reasonable charge and starts the engine easily.  A starter battery does need to deliver a decent current (~150A) but only for seconds, so capacity of the battery is not so significant.

[Kendorr]

I'm using one of these

https://advancedbatterysupplies.co.uk/product/advanced-lxd110-dual-purpose-leisure-battery/

the service ABS provide is very good.

[mrsmelly]

You dont need to spend more than 80 quid tops for a starter battery. You do need to clean the terminals up though.

[Momac]

Quite  few years ago wrecked an alternator running a car with a near dead battery.

A new battery is usually cheaper than an alternator.

For a dedicated engine start battery you don’t need 100Ah but that’s not an issue in itself. For a smaller engine such as on  a narrowboat a smaller starter battery should be sufficient – say 80AH.

as said the CCA value is what you need - as high as possible. 

Halfords do reasonable starter batteries under their own brand , perhaps not the cheapest but reasonably priced. . I have one for my bow thruster and it seems fine after 5 years use... which is year longer than the 4 year guarantee.

[bizzard]

Unlike cars which are generally used frequently boats are often used infrequently so they need a decent sized start battery for the reserve especially if an indiect injection engine which heaters can whack the battery before even an attempt to start it. I think Pedro has a wide beam boat with probably a 50hp engine, I would put no lower than 100amp start battery in it.

[Richard10002]

I have a 100Ah starter battery. Generally, when starting, I turn the key to the heater position for 10 seconds, then all the way to start it up. Usually starts pretty much immediately, perhaps a few seconds.

 

Apropos of nothing: If the engine/heaters draw 600A for as much as a minute, I think 10Ah is used. If my engine didn’t start within a minute or two of trying, I think I would accept that something is wrong, and stop trying.

[Keeping Up]

Something I often wonder; the heater plugs take a fair bit from the battery for say 10 seconds, so the battery will be better able to deliver the starter current if it has a few seconds to recover but during that interval the plugs will be cooling down. So, is it better to pause or not to pause?

[MtB]

1 hour ago, Keeping Up said:

Something I often wonder; the heater plugs take a fair bit from the battery for say 10 seconds, so the battery will be better able to deliver the starter current if it has a few seconds to recover but during that interval the plugs will be cooling down. So, is it better to pause or not to pause?

 

 

I think the heater plugs will stop glowing red within a second or two if you wait a few seconds before turning the engine over, therefore best not to pause.

 

In addition, I always imagine the heater plug current continues to flow keeping them warm during cranking. Dunno if this is true, but probably is. 

 

 

[pedroinlondon]

On 15/10/2019 at 10:46, Jen-in-Wellies said:

Does the engine normally start easily? If so, then you can probably safely go for a smaller battery. Cold cranking amps is a better specification to match with the old battery than amp.hour capacity. If going to a smaller battery, then make sure that the battery is held down properly, so it can't move, so it can meet the boat safety scheme requirements. Distance between terminals isn't important. The big red and black wires being able to reach the terminals is! Try a motor factors, or commercial vehicle parts suppliers for getting a new one, if you don't want to mail order.

 

Jen

Thanks Jen

I was only trying to avoid rearranging the cabling and the support battens I have to secure the existing battery.

The engine does start well usually.

 

21 hours ago, bizzard said:

Unlike cars which are generally used frequently boats are often used infrequently so they need a decent sized start battery for the reserve especially if an indiect injection engine which heaters can whack the battery before even an attempt to start it. I think Pedro has a wide beam boat with probably a 50hp engine, I would put no lower than 100amp start battery in it.

Hi Bizzard

 

It's nearly 50hp and indeed I only use the engine for cruising once or twice a month. Never run it to charge the batteries unless the Sun is unavailable also.

Thanks

[WotEver]

5 hours ago, pedroinlondon said:

I was only trying to avoid rearranging the cabling and the support battens I have to secure the existing battery.

Your existing battery will have a type number on it - something like 110 or 115 or 019. If you buy the same type then the dimensions will be the same. 
 

Or simply use Tayna’s convenient interactive tool:

https://www.tayna.co.uk/tools/battery-wizard