Starter Battery

[Idle boater]

Hi folks,      I need to replace my starter battery as its been in position for a good few years the stickers have long gone, But the company I'm dealing with want to know what ah the battery is, its ti start my 1.5 bmc engine. Any techno bods have any ideas please, its a lucas.

 

                                                                                                                 many thanks     Mike

[Tony Brooks]

Just measure the dimensions and note the post position and tell them. Anything of typical dimensions will be about twice the  Ah you need. Size & post layout is usually more important on a boat so it will just fit straight in with no messing.

[Nut]

this is in my 300tdi will it fit in your tray?

 

Numax CXV24MF
Specifications
12V 86Ah, Cold Start Marine Cranking Amps: 1000A (equiv about 7-800)
Deep-cycle & Starting
Sealed Lead Acid

[Tony Brooks]

For goodness sake do not get mixed up with sealed batteries unless  you have a very good reason to.  With open cell batteries the "service intervals" these days seem much the same as for sealed but now and gain you can look inside them and if done several times a year you gan get a handle on the start of failure AND they are far easier to test using Sp. Gr./relative density.

[Idle boater]

Thanks for the input guys, I did give them the dimensions and post position tony but they still say they need the a h.

[philjw]

Just now, Idle boater said:

Thanks for the input guys, I did give them the dimensions and post position tony but they still say they need the a h.

I wonder why. It's CCA that is important for a starter battery.

[George and Dragon]

Probably because they don't understand the application.

 

All your starter battery on a boat does is turn the starter motor and perhaps the bilge pump.

 

On a vehicle it also runs all sorts of accessories which mean the manufacturer specifies Ah as well as CCA

 

[George and Dragon]

This website might be useful - ETA you can pick a suitable capacity since you know the dimensions...

Edited July 25, 2018 by George and Dragon
additional info

[MtB]

Why does it need replacing anyway?

 

I'm not sure you said, other than you said you've had it several years. My starter battery is about 12 years old and works fine.

 

 

 

 

[Idle boater]

its not holding a charge, and will not turn the engine over, I had it on charge overnight two nights ago and its as flat as a fart this morning, water levels are ok.

[MtB]

9 minutes ago, Idle boater said:

its not holding a charge, and will not turn the engine over, I had it on charge overnight two nights ago and its as flat as a fart this morning, water levels are ok.

 

Hmmm. 

 

You're probably right but I've replaced enough starter batteries in my life only to find the symptoms return three weeks later, to want to do a bit more checking before lashing out on a new battery. 

 

 

[Tony Brooks]

27 minutes ago, Idle boater said:

its not holding a charge, and will not turn the engine over, I had it on charge overnight two nights ago and its as flat as a fart this morning, water levels are ok.

As per voltage checks at the lead posts both cranking/attempting to crank and not cranking or because it will not turn the engine over? If the latter (all together now) Does your master switch have a plastic key?

[Idle boater]

yes a big red plastic one ???

 

[Momac]

40 minutes ago, Idle boater said:

yes a big red plastic one ???

 

They are prone to failure.

The switch - not so much the key.

[WotEver]

54 minutes ago, Idle boater said:

yes a big red plastic one ???

Take the key out. Roll up a bit of paper maybe the size of a fat pea. Drop it in the hole. Reinsert the key. 

 

Does your engine now now turn over?

[Idle boater]

I will try in the morning, thanks

[Tony Brooks]

11 hours ago, WotEver said:

Take the key out. Roll up a bit of paper maybe the size of a fat pea. Drop it in the hole. Reinsert the key. 

 

Does your engine now now turn over?

Or test the voltage as I described on the battery lead posts and put the readings here.  That will tell us if the battery is as you describe it (dead flat) or you have another fault like dirty battery terminals and so on.

[Psycloud]

16 hours ago, Idle boater said:

Hi folks,      I need to replace my starter battery as its been in position for a good few years the stickers have long gone, But the company I'm dealing with want to know what ah the battery is, its ti start my 1.5 bmc engine. Any techno bods have any ideas please, its a lucas.

 

                                                                                                                 many thanks     Mike

Have you looked on Eurocarparts.com?  I bought a Bosch S3 for my boat recently and with the code JULY70 (35% discount) got it delivered for about £100 (and that's a big battery).  You can see the measurements on all the batteries and compare like Tony says. 

 

https://www.eurocarparts.com/ecp/p/car-parts/car-electrics-and-car-lighting/electrical/car-battery/?444770965&1&cc5_1004

Edited July 26, 2018 by Psycloud

[WotEver]

3 hours ago, Tony Brooks said:

Or test the voltage as I described on the battery lead posts and put the readings here.  That will tell us if the battery is as you describe it (dead flat) or you have another fault like dirty battery terminals and so on.

I was working on the assumption that OP either doesn’t have or is reluctant to use a multimeter, based on the fact that we’ve had no voltage readings to date. A scrap of paper however is likely to be to hand

[Tony Brooks]

5 minutes ago, WotEver said:

I was working on the assumption that OP either doesn’t have or is reluctant to use a multimeter, based on the fact that we’ve had no voltage readings to date. A scrap of paper however is likely to be to hand

Fully agree, but if he finds that does not help he has two choices, try voltage testing or try a new battery. Both have a close to 50% chance of not being the answer and if he goes for a new battery but has dirty/corroded clamps or a loose termination he may think he has cured the problem only for it to reappear in a short time. I was just trying to reinforce that what you said may not provide a definitive test for whatever problem he has.

 

Sometime I think the CaRT & EA license conditions should demand the boater demonstrates some degree of competence in using a meter.

Edited July 26, 2018 by Tony Brooks

[George and Dragon]

A basic Fluke multimeter is £61 on Amazon. A new starter battery £???

 

Cheaper meters are available but I wouldn't like to rely on their readings

[rusty69]

I have one of the uni-t meters, often mentioned on here. 20 quid delivered, i find it quite acceptable. 

[Rob-M]

1 minute ago, rusty69 said:

I have one of the uni-t meters, often mentioned on here. 20 quid delivered, i find it quite acceptable. 

Same here, used it recently to check batteries when NASA BM2 was showing 11v.  Quick disconnection of each battery and check with uni-t showed each battery at 12.7v so disconnected and reconnected the BM2 which then also showed 12.7v which was a relief as first thought was knackered battery bank.

 

 

[Nightwatch]

I haven't read the whole thread. I have had good service and delivery from abs. Advance Battery Supplies.