New start battery

[blackrose]

I saw another recent start battery thread somewhere but can't find it now.

Anyway, it looks like I need a new start battery as it won't turn the engine over even if I heat the glow plugs for about 20 seconds. The start battery has been on charge and is showing 12.8v on my battery monitor but it doesn't like the cold temperatures. I've got a neat 'emergency parallel' switch between start and domestic isolators so I've been using the domestics to start the engine.

It's nearly 13 years old so it's lasted well (Hi-Phase 110a/h leisure). Should I just go for a car start battery with the same a/h rating and approx the same physical dimensions so it fits into the box? I wonder why the builders fitted a leisure battery?

[matty40s]

5 minutes ago, blackrose said:

.... I wonder why the builders fitted a leisure battery?

That's all they had in stock is the most likely answer. It's the cold cranking capacity that's important in a starter, I would only fit a leisure as a short term measure, however, yours seems to have done quite well.

[Naughty Cal]

We just fitted the biggest starter battery that our local battery supplier had in stock at the time. It's been on 8 years now no problems.

[blackrose]

Is the cold cranking capacity given on the battery or just in the specs? I assume the latter. What units of measurement are used for cold cranking capacity and what sort of capacity should i be looking for to turn over a modern 55hp engine? 

[WotEver]

1 minute ago, blackrose said:

Is the cold cranking capacity given on the battery or just in the specs? I assume the latter. What units of measurement are used for cold cranking capacity and what sort of capacity should i be looking for to turn over a modern 55hp engine? 

CCA is usually on the battery label. Simply go for the highest number you can find in a battery that will fit the space available. 

[matty40s]

1 hour ago, blackrose said:

Is the cold cranking capacity given on the battery or just in the specs? I assume the latter. What units of measurement are used for cold cranking capacity and what sort of capacity should i be looking for to turn over a modern 55hp engine? 

you will normally find a 663 or 664 on a boat battery, this is a rough guide - truck engines about 7-800.

On testing, a decent new batttery will have a CCA of 8-900, anything reading at or below 450-500 will start to struggle in cold weather or with a 'difficult' engine.

[PaulJ]

Give Bedford Battery a ring Blackrose- they have a place in Northampton and are helpful and local to you. Chap who works there is brilliant at alternator/starter motor repairs which is always handy if ever needed too.

[Jen-in-Wellies]

I was in a similar position early this year. The 110AHr leisure battery that had been fitted for the engine died and needed replacement after ten years. Fortunately I had a set of jump leads on board to start the engine from the leisure batteries and get back to my mooring. In the end I went for a small car battery, 063 size, if I remember correctly. The engine is a Beta 43 and starts very reliably, so a large, high capacity battery wasn't needed. I was moving the heavy leisure batteries to a different position to get rid of the boats lean to port anyway, so making a new battery tray and hold down clamp for a smaller start battery wasn't a problem. Can't remember the CCA rating for this, but it has been more than adequate.

Size the battery for how hard the engine is to start. The longer the glow plug time, higher the glow current and the longer it needs cranking before it fires, then the bigger the battery.

Jen

[MtB]

4 hours ago, blackrose said:

I wonder why the builders fitted a leisure battery?

 

I expect it was because they just didn't care it would last only thirteen years....

[mrsmelly]

5 minutes ago, Mike the Boilerman said:

 

I expect it was because they just didn't care it would last only thirteen years....

Your on form tonight Mike

[MtB]

9 minutes ago, mrsmelly said:

Your on form tonight Mike

 

Thanks!

It's probably just the Cotes Du Rhone La Grange St Martin talking...

[Nightwatch]

That's easy for you to say!!

[blackrose]

16 hours ago, PaulJ said:

Give Bedford Battery a ring Blackrose- they have a place in Northampton and are helpful and local to you. Chap who works there is brilliant at alternator/starter motor repairs which is always handy if ever needed too.

Thanks All.