Starting battery for a VP MD2030

[Ruffles]

Thinking of a dedicated started battery for a MD2030. Any one know the CCA required? It doesn't seem to be in the manual.

I'd rather buy a standard (car) physical size if at all possible since I'll have to build a slot in the engine bay and I want my work to outlast the battery.

In fact, has anyone found an online reference for physical battery sizes? I believe there are standards.

All this so I can have a fridge....

 

[john_morris_uk]

From the workshop manual:

The starter motor is rated at 1.2kW. ie 100 amps at 12 Volts

The manual also suggests a 70 Ah starting battery.

Hope that this helps.

 

[MrCramp]

I understand what you have posted but given that information I would not know which battery to buy as in a car spares shop (or Halfords) all that is quoted is CCA.

I think (but do not know for sure) the MD2030 is a 3 cylinder engine, about 20hp and about 950/1000cc. In that case I would go into Halfords and look at their reference book, which is near their batteries, and see what is spec'd for say a 1200cc (or VW/Ford 1400cc, because I think such an engine is used ) diesel. I would buy a starting engine for a car engine bigger than the boat engine so I had some spare capacity. I would then go and shop around for the best priced battery.

 

[pvb]

VP suggest a 70Ah battery for the 2030. A typical 70Ah car battery will have a CCA rating around 500 to 600, which is more than sufficient (the 2030 starter draws about 100A). I'd suggest a sealed maintenance-free battery would be ideal, available everywhere. The Halfords Calcium range is OK, and has a 4 year warranty.

 

[Ruffles]

Thanks John,

Interesting recommendation for battery capacity. Looking at small car batteries these seem to rate 300 CCA with a capacity of around 40 Ah. So why do they specify 75Ah?

Is the relationship between CCA and starter power more complex than it seems?

Obviously a diesel needs more torque to start than a petrol engine. But a 1.6l diesel ford fiesta specifies a 500CCA battery so 300 seems adequate for my 1 litre engine. I'm anxious to use as physically small as possible because of space restrictions but would rather use cheapo car units rather than pricey red flash batteries others have recommended.

 

[Ruffles]

I wonder if the CCA capacity needs to meet the peak current as each cylinder compresses and is therefore higher than the current inferred by the starter motor power? A 3 cylinder engine will therefore draw higher peak current than the same sized 4 cylinder. So my 1 litre VP may equate to a 1.4l car diesel?

Any suggestions as to where to put this new battery? Clean responses only pleeease....

 

[davidbains]

I don't have a seperate starter battery. The Red Flashes are too expensive and why buy a small battery just for one short job. I bought another 100AH battery and parralleled it with the existing 110AH one to make a combined 210AH service and starter battery. It runs the fridge all day and doesn't even notice starting a Yanmar2GM20. I know this is not what's recommended, but I and many others have done this for years. I did buy another battery for the windlass though!!

 

[pvb]

[ QUOTE ]
I wonder if the CCA capacity needs to meet the peak current as each cylinder compresses and is therefore higher than the current inferred by the starter motor power? A 3 cylinder engine will therefore draw higher peak current than the same sized 4 cylinder. So my 1 litre VP may equate to a 1.4l car diesel?

[/ QUOTE ]Sorry, don't follow your reasoning.

You should ideally locate the battery in a cool ventilated place, close to the engine so as to minimise length of wiring runs.

 

[asj1]

Go to a motor factors and ask for a battery for a DIESEL transit. It will certainly be up to the job and you will be surprised how cheap it is -- much cheaper than Halfords !

 

[VicS]

[ QUOTE ]
Go to a motor factors and ask for a battery for a DIESEL transit

[/ QUOTE ] What year sir? They have been making Transits since about 1972.
What model?

Oh it's for a boat, we will not be able to give you a guarantee then.

 

[Stemar]

""Cold cranking amps" is a rating used for starting batteries only and is intended to demonstrate a battery's ability to start an engine during winter. It measures the number of amps that a 12-volt battery can deliver at 0°F / -17.8°C for 30 seconds while maintaining a voltage of at least 7.2 volts."
. http://www.sailgb.com/sshop/tech_info.asp?ID=226

1.2KW at 7.2v is 167 amps. I'm no expert, but if I've understood things correctly, you don't really want to run a battery below half capacity, so if you want to be able to turn the engine over for 30 seconds in cold weather you want a minimum of 400cca and 5-600 certainly isn't excessive.

When the brass monkeys stop worrying and accept that a future as a eunuch is inevitable, your engine will need some serious churning to get it going. My Focus diesel starts on the first kick in reasonable weather, but the manual says that it could take 30 seconds or more continuous churning to fire up at 0F, hence the need for serious capacity.

Build a battery box that's too small and you'll regret it until you finally rip it out and do it again properly. One that's big enough and holding ample capacity is something you'll appreciate long after you've forgotten what a pain in the nether regions it was to fit.

The diesel Transit battery does sound like a good idea. Costco's well worth a look for batteries if you have access to a card.

 

[Stork_III]

Try http://www.carbatteryshop.co.uk or Google Varta. Should give all you need to know re size/AH/CCA.

 

[chiefeng]

Rob
Have you tried the Moody owners website technical library. There's an excellant dissertation on batteries there.
Rgds
Bob

 

[alldownwind]

[ QUOTE ]
Rob
Have you tried the Moody owners website technical library. There's an excellant dissertation on batteries there.
Rgds
Bob

[/ QUOTE ]
.....but only available to MOA members......

 

[reeac]

[ QUOTE ]
[ QUOTE ]
I wonder if the CCA capacity needs to meet the peak current as each cylinder compresses and is therefore higher than the current inferred by the starter motor power? A 3 cylinder engine will therefore draw higher peak current than the same sized 4 cylinder. So my 1 litre VP may equate to a 1.4l car diesel?

[/ QUOTE ]Sorry, don't follow your reasoning.

You should ideally locate the battery in a cool ventilated place, close to the engine so as to minimise length of wiring runs.

[/ QUOTE ]

The reasoning, I think, is that the fewer the cylinders the greater the cranking power required as all of the engine swept volume will be concentrated into one compression stroke rather than several. I think that this might be valid but the difference between 3 and 4 cylinder engines is probably small. The effect might show up with a single cylinder engine. A quick search of an old [Jan. 2004] car mag. shows that the VW Polo was [is?] available with a 1422 cc 75 bhp. 3 cyl. diesel engine. If you were keen you could compare its battery spec. with that of a Fiesta 1398cc. 67 bhp. diesel which is 4 cyl.

 

[stubate]

the std one fitted to my bene 351 vp2030 was a 65 amphr, it came with a 60 amphr from the canaries, it lasted 2 years, i dont know how old it was, i then fitted a bog std 65 amphr generic lead acid, it is still going strong 2 years later.
stu

 

[andy_wilson]

Before you \"build a slot in the engine bay\"...

... it might be worth checking the temperature the engine bay typically reaches - especially on a long motor - sail, and research the effect of this on charging and self discharging of the choosen battery type, and also the ageing effect.

Car batteries under the bonnet benefit from plentiful airflow with just a thermal blip on shut-down.

 

[alldownwind]

[ QUOTE ]
A quick search of an old [Jan. 2004] car mag. shows that the VW Polo was [is?] available with a 1422 cc 75 bhp. 3 cyl. diesel engine. If you were keen you could compare its battery spec. with that of a Fiesta 1398cc. 67 bhp. diesel which is 4 cyl.

[/ QUOTE ]
We run a 1.2L 3-cyl Polo, 50hp (I think), has a 60Ah battery, 480CCA if that helps.

Our starting batt on the boat, VP2020 engine, is a dinky little sealed 28Ah, 600CCA, bit pricey but can be installed anywhere, anyway up (which is a help given the space I have) and what the heck it has a no-quibble 5-year guarantee.