starter battery question

[davidc]

As no one will be surprised first cold snap and my starter battery has failed, in fact giving up the ghost

am I right in assuming that as its the start battery, any cheap car battery will be OK as a replacement.

[Dave Payne]

I would treat it like any diesel car, needs plenty of amps to crank it over...

 

When you say cheap, do you mean halfords cheap?

[davidc]

I would treat it like any diesel car, needs plenty of amps to crank it over...

 

When you say cheap, do you mean halfords cheap?

 

Yes if that size and type is OK

[Dave Payne]

i don't see why not, maybe someone else will say if i am wrong...

 

 

Guess the only issue is matching the battery to the engine, with a car you can tell them what engine and they tell you what battery you need, guess they will struggle if you say BMC engine...

[davidc]

Monty does not have a large engine its a shire 1000

[MikeV]

Assuming a typical 35-45HP engine look for a battery which has a quoted CCA (Cold Cranking Amps) specification of at least 600 amps. 750 would be better. My start battery has also just died but I can start the engine by bridging to the domestic bank and can see that the starter motor pulls around 180-200 amps. The CCA will obviously degrade over the battery's life so you want a generous margin.

[davidc]

Assuming a typical 35-45HP engine look for a battery which has a quoted CCA (Cold Cranking Amps) specification of at least 600 amps. 750 would be better. My start battery has also just died but I can start the engine by bridging to the domestic bank and can see that the starter motor pulls around 180-200 amps. The CCA will obviously degrade over the battery's life so you want a generous margin.

That's how I started the engine today but I can not tell what the amps used where , except the jump lead I used was warm after the jump.

[Taslim]

I would treat it like any diesel car, needs plenty of amps to crank it over...

 

When you say cheap, do you mean halfords cheap?

Plenty amps (CCA) yes'

 

Halfords cheap, or other high street retailers cheap 'aint nessisarily cheap.

 

A local motor electrics firm fixed me up with a budget battery for 1/3rd of the price of similar from big H & three years on it's still going strong.

[alan_fincher]

Yes, it does need to be suitable for starting a largish diesel, (which have far higher compression to overcome than a petrol engine).

 

A diesel car usually has a significantly bigger battery than a petrol model of the same type of car.

 

Halfords will usually not be cheap, so unless you are desperate don't go that route, as you can always buy a similar spec battery elsewhere for less.

[bottle]

Just one extra point, check the dimensions and make sure it will fit the space available.

[Burgiesburnin]

Just one extra point, check the dimensions and make sure it will fit the space available.

 

And that the polls are the right way round for your cables.

[Alan Saunders]

Any decent battery factor (not Halfords) or boatyard will supply a 90Ah starter battery for <£100, maybe <£70.

Yes, check the dimensions and the position of the + and - terminals.

 

I do not have the number to hand but there is a standard battery that fits most boats and older vehicles like Land Rover S3.

Mine is in the boot of my car that needed a jump-start at 9pm last night.

 

Yes, diesels need more capacity if they have heaters and to cope with the higher compression ratio but the starter motor only has to cope with a single cylinder.

i.e. a single cylinder 1 litre engine needs the same start current as a 3 litre, 3 cylinder engine etc.

[by'eck]

Any decent battery factor (not Halfords) or boatyard will supply a 90Ah starter battery for <£100, maybe <£70.

Yes, check the dimensions and the position of the + and - terminals.

 

I do not have the number to hand but there is a standard battery that fits most boats and older vehicles like Land Rover S3.

Mine is in the boot of my car that needed a jump-start at 9pm last night.

 

Yes, diesels need more capacity if they have heaters and to cope with the higher compression ratio but the starter motor only has to cope with a single cylinder.

i.e. a single cylinder 1 litre engine needs the same start current as a 3 litre, 3 cylinder engine etc.

 

Can't agree with that statement although I understand your thinking. In your example the multi-cylinder engine will present the load peaks more often so creating a greater average load unless by chance it fires almost instantly. Probably more relevant is the extra load from turning over multi-cylinders with multi-bearing crank running in cold oil.

 

A fully decompressed cold JP3 will be harder to turn over by hand than a JP2 for example.

[davidc]

Just been out looking at the cheap car battery's from a few suppliers and the cheap ones are 280 amps cranking when I looked at the 580 amp cranking plus there was little difference with the chandlers price and car battery's now have the terminals along the longest side not the short side like mine in the boat.

 

So I will go with the chanders

 

thanks for the advice everyone