Volvo Penta 2002 18hp - Which Battery ?

[Newman]

Evening all,

I may have to buy a new battery for a Volvo Penta 2002 18hp engine. I have just bought a 1990 Bavaria 300 and (now) am given to believe the engine battery does not hold a charge. The boat is in Ipswich, some miles from me, and I want to move it this Saturday. I can't get to it before the move to verify the size, type etc of the existing battery and am thinking of buying a new one to play safe. I therefore have two questions:

Can anyone please advise on a suitable type of battery and cost (funds are a bit limited - aren't everyones !) ?

Can anyone also advise on where I might 'pick up a bargain battery' of the appropriate type in the Ipswich area tomorrow (Friday).

Cheers all

 

[VicS]

If you read the owners manual you will find that the recommendation is 70Ah maximum

http://vppneuapps.volvo.com/ww/PIE/...403&d=Owners Publication&s=2512225&lang=en-GB

Nobody has ever explained satisfactorily why they quote a maximum, but they do.

Unfortunately they do not suggest a CCA rating.

Therefore a 70Ah battery of your choice but check the terminal layout. It may or may not be critical, depending upon the lengths of the connecting cables.

There are loads of battery suppliers in Ipswich. See Google.


Bavaria owners association http://www.bavariaowners.co.uk/homepage/homepage.php

Bav 300 should have two batteries . Both dead ? or are they dedicated starter and house batteries. Not possible to crossfeed?

 

[MoodySabre]

If it is just a starter battery then one sold for diesel cars would do - I have one that is rated 74AH nad marked 400CCA and it starts my VP2003 easily. No need to pay chandlery prices.

Don't know Ipswich but must be plenty of car spares places.

 

[gianenrico]

Evening all,
Cheers all

IF engine is in good order, 70 ah is good enough; had ffor 116 years (trice changed battery, of course).

Probs might arise from terminals lay-out; if you are in a hurry, prepare a couple of 3 feet (one meter) cables of good size (70 sq. mm) ready to be connected to the exixting ones and to the battery, so you can rig a serious temporary connection.
Cheers.

 

[reeac]

You could buy a jump start battery pack for under £50. [I paid £40 for mine]. That would get you going and you could then assess condition of the present boat batteries and if necessary replace at your leisure once you've assessed available space and cable constraints. Then keep the jump start pack for emergencies. I know that sounds like buying two batteries rather than one but it would ease the time pressure and allow you to shop around.

 

[Plevier]

Hello Newman

If it is ONLY for engine start you really don't need anything like 70Ah.
My 2 litre diesel car has that size to support everything on it; the Volvo 2002 is only about 600cc.
Any small-medium car battery will do it. 250CCA should be enough. A 70Ah is likely to be 400-600CCA. My mate's Bav 30 has 2 x 70Ah on the domestics and about a 35Ah to start the VP 2020.
I don't know any places in Ipswich, just phone a car shop or two.
If it's doing domestics as well then yes, you need the biggest you can fit.

I hope your journey goes well, it's not looking too nice just now. I brought mine back from Ipswich last weekend so won't be seeing you out there after all! The wind turbine towers and big SW mark point you nicely into Foulger's Gat now. Didn't see any work going on, just a crane in the distance. It was B cold.
Sat left Ipswich 06.00 into the lock, arr Dover 19.00.
Sun left Dover 07.30, arr Shoreham 20.00.

Is your boat from a yard in Ipswich? My new (used) one is from Burton Waters at Ipswich Haven, from their traded in stock not brokerage. I have been impressed with their service overall. Very helpful and with a very good contract guy - Mike Pacey(? I think) - doing the jobs for them.

 

[VicS]

If it is ONLY for engine start you really don't need anything like 70Ah.
My 2 litre diesel car has that size to support everything on it; the Volvo 2002 is only about 600cc.
Any small-medium car battery will do it. 250CCA should be enough. A 70Ah is likely to be 400-600CCA. My mate's Bav 30 has 2 x 70Ah on the domestics and about a 35Ah to start the VP 2020

Dont forget that the 2002 is not the easiest of lumps to start. Unlike diesel cars and the MD2020 it does not have glowplugs so comparison with either is not entirely valid.It relies on a good powerful battery to crank it until it fires. ( Its capacity incidentally is 0.85 dm³)
A 60 or 70 Ah battery will do the business for sure. It would be sad to buy a much smaller battery and then find that in cold weather or when it gets beyond a couple of years old it just isn't up to the job.

Another thing for the OP to check before buying are the dimensions of the battery space. Batteries are not all of the same physical size or relative proportions even for the same capacity.

 

[BAtoo]

As others have said 70ish AH, as much CCA as you can get in that size. Probably go for a diesel one too. You will be rally unlucky if the terminal placing is wrong as most boats I've seen have a decent play on the leads.
If your boat is in a yard in Ipswich you will have quite a walk to a car shop( unless you have a car available or take a taxi) so you will be paying chandlery prices.....
Maybe worth getting the emergency start kit and take with you....

 

[Plevier]

I try not to be contentious on here but I have to take issue on this. My comments are based on several years working in a technical/applications role for a large battery manufacturer.

CCA depends much more on battery design in terms of current paths and acid diffusion than on capacity. I could show you a specialised 20Ah lead acid battery that will give you 1500A peak current and 350A CCA. I used to use one even smaller than that to start a 4 litre aircraft engine. You do not need a 70Ah battery to start a <1000cc boat engine!

CCA typically (there are several variants) tells you the constant current you can get for 30 seconds at -18 deg C. So at the full rated 350A you are taking out less than 3Ah in the discharge. Nominal capacity is pretty irrelevant. Give it a minute or two for acid diffusion and you'll be able to get almost the same out again.

The VP2002 starter is about 1kW. Initially it probably takes maybe 250A for a fraction of a second to get turning then it's going to settle to maybe 100A, so for 30 seconds that would be around 1Ah taken out. Have you ever listened to an engine cranking for a genuine 30 seconds? It seems for ever! Try timing it! I never timed my 25 year old 2002 (that I had until last week) but I would estimate it normally started in 5 seconds or less. That would be about 0.15Ah. I can recall one time in freezing weather when I was getting slightly anxious; it had probably taken 10 seconds. Let's say 15 to be generous, and then double it for very cold oil thicker than normal; that would be about 1Ah taken out. Still peanuts.

The CCA is 30 seconds at deep freeze temperature; that's a world of difference.

Many starters need 10 minutes to cool after a 30 second crank. It is an extreme duty.

On the 2020 I have now the heater plugs are fused at 15A. Let's say they take 12A, I'm guessing, and you use them for the max permitted 30 seconds. That's 0.1Ah - not far off the capacity taken to start the 2002 without heater plugs in normal conditions.

So a 35Ah (or less) small car battery is going to cope with a 2002 without breaking sweat. What's more, it will do it even when it has deteriorated a lot in capacity. Think about when you used to have an old car with a knackered battery, before you became a rich yacht owner - it would start OK if you went straight to it, but leave the lights on for a few minutes and it wouldn't cope.

In the same way, the heater plugs on a 2020 could in such a case make it less likely to start by taking out the tiny bit in the battery before you even try to crank! OK, that's a bit tongue in cheek, and you certainly shouldn't be relying on a battery in such a state, just making the point that there's more to it than initially meets the eye.

Battery size selection for cars is in fact much more a function of reserve capacity (the auxiliary load it will supply for 20 minutes, like heated screen, fan etc, when you're in a traffic jam) than of CCA. This is why car batteries have got bigger.

I don't like the argument that if you get an oversized battery it will last longer i.e. more years. Old batteries don't just fade away gracefully. They can die suddenly - internal open or short circuit - leaving you suddenly with no capability at all.

I really feel you are better to get a sensibly sized battery and replace it more often. The high reliability standard - for aircraft and safety critical installations - is to replace when capacity on an 8 or 10 hour rate test discharge falls to 80% of rating. Beyond that the battery is considered unreliable. (It would probably still pass a 30 second high rate discharge test at that point however.) The average life figure for car batteries in the UK used to be 5 winters to the point of unreliable starting on a cold morning, i.e. when most people reached replacement point. Not a good idea to push it so far on a boat. I know people are now going to come up with stories of 10 year old batteries working perfectly; I'm talking about the average life for average quality car batteries in average use. It might be 6 or 7 years now, the 5 year figure goes back some years and standards have improved.

This solution conveniently fits the OP's desire for minimum expenditure now, as well as being recommended practice.

A comparison - my lawnmower has an 18HP engine too (admittedly petrol) and that has a 10Ah starter battery that has lasted several years. I'm confident the same battery could start the 2002.

I do stress I am taking the OP's statement that this is only for engine starting literally. If this battery is to be used for domestic loads as well, then yes, you want the biggest possible and preferably not a vehicle starter battery. "Leisure" battery is a pretty meaningless term but if it's from a decent maker, they will have done something to justify the term - probably thicker plates and extra separation - so it may well be more durable. That's a whole extra topic!

 

[vyv_cox]

As a guide, all the 1, 2 and 3 cylinder Yanmar GM engines have a CCA requirement of 200 Amps.

I use a Red Flash 900 AGM battery for starting a Yanmar 3GM, 13 Ah and 420 CCA. It works but only just and with hindsight I would buy the Red Flash 1000 with twice the capacity.

 

[Plevier]

As a guide, all the 1, 2 and 3 cylinder Yanmar GM engines have a CCA requirement of 200 Amps.

I use a Red Flash 900 AGM battery for starting a Yanmar 3GM, 13 Ah and 420 CCA. It works but only just and with hindsight I would buy the Red Flash 1000 with twice the capacity.

Vyv

Where do you get 420CCA from? By normal standards it's rated at 156CCA - see http://www.dmstech.co.uk/pdfs/battery_redflash_hr_01.pdf

Even I wouldn't go as small as that! I think the 1000 would be more appropriate.

PS I see the 420CCA is off the Tayna website but with no parameters defined. I would trust the figure from DMS who are responsible for this battery as you will see from the label.

 

[vyv_cox]

Vyv

Where do you get 420CCA from? By normal standards it's rated at 156CCA - see http://www.dmstech.co.uk/pdfs/battery_redflash_hr_01.pdf

Even I wouldn't go as small as that! I think the 1000 would be more appropriate.

PS I see the 420CCA is off the Tayna website but with no parameters defined. I would trust the figure from DMS who are responsible for this battery as you will see from the label.

I see what you mean! I have found the 420 CCA figure on a number of sites, not only Tayna. In a small search just now I may have found the answer. The 156 CCA figure is at -18C (which may well be the normal standard?) I found this site which gives various CCAs at different temperatures. It doesn't include the 900 but the similar 750 is rated at 440 CCA at 20C.

I used the 900, which seemed to be sufficient, because it fits the space I wanted it in. It turns the engine over fine when fully charged but after a week or so of not being charged it struggles.

 

[Plevier]

CCA is -18C or 0F for 30 secs to 7.2V (i.e. 1.2V per cell). That voltage is under load and jumps up as soon as load removed. You don't keep to the 10.8 volts or whatever "rule" for high rate discharges.
That is the real original standard but some variants seem to have been introduced:

MCA (marine cranking amps) or just CA is 0C/32F for 30 secs (I suppose that's recognition that if you are floating in water it can't be at -18!)
HCA (hot cranking amps) is 20C/68F for 30 secs
IHCA (instant hot cranking amps) is 20C/68F for 5 secs (an attempt to simulate a more normal case with an engine that starts well)

The website you found says
Red Flash batteries use technology based on that developed for starting jet engines in military aircraft. They have been designed to provide very high current whilst maintaining a high stable voltage. The pure lead thin plate design differs from ordinary battery systems and gives a very much lower internal resistance, enhancing high current capability.

That was true. Those were the aircraft batteries I was referring to and we used to supply them to DMS (not to aircraft spec and derated, but essentially the same). However things have moved on and I don't think the 900 uses the thin lead sheet plates. I would have thought 420 would be more like its 5 second than 30 second rating but that's not gospel.

In fact, the DMS website gives the HCA (it doesn't call it that but it says 20C 30secs) for the 900 as 255A, so 420A must be a very short duration figure. Still impressive for that size of battery but not quite what was claimed! Hence the price.

If it loses perceptibly in a week that supports my assumption about construction. The lead sheet ones have extremely low self discharge.

All these figures are based on batteries in perfect condition and absolutely fully charged. An element of selection of the best from the batch may creep into it.

If your starting battery is only charged from the engine alternator, without a smart regulator (a bit dodgy to use with AGM, may shorten the life), it probably never gets above about 85% state of charge. Most car batteries range between 50% and 85% in service. That will affect the CCA a bit, not hugely.

Overall I think you are pushing it to the limit!

 

[VicS]

working in a technical/applications role for a large battery manufacturer.

You are then the perfect person to explain why VP quote a maximum Ah for a number of their engines.

I have a theory, and I have posted it here in the past, but it was rather one I made up as I went along.

I have seen the same explanation elsewhere but I don't know if I had got it right or if that was just my own theory going full circle and coming back to me!

 

[Plevier]

You are then the perfect person to explain why VP quote a maximum Ah for a number of their engines.

I have a theory, and I have posted it here in the past, but it was rather one I made up as I went along.

I have seen the same explanation elsewhere but I don't know if I had got it right or if that was just my own theory going full circle and coming back to me!

No idea sorry! The alternator at 50A rating is capable of handling a bigger battery and should be protected against overcurrent anyway.
My only guess is that it might be that they are making assumptions about short circuit current and protecting their wiring, starter contacts etc in case of liability claims.
My 2002 is connected to 2 x 65Ah in parallel, top quality Varta starter batteries (I know, I know, but they came brand new with the boat!) that would greatly exceed the discharge current and charge current acceptance figures of a 70Ah battery of 25 years ago.
It hasn't complained!

 

[vyv_cox]

If your starting battery is only charged from the engine alternator, without a smart regulator (a bit dodgy to use with AGM, may shorten the life), it probably never gets above about 85% state of charge. Most car batteries range between 50% and 85% in service. That will affect the CCA a bit, not hugely.

Overall I think you are pushing it to the limit!

I have a Sterling alternator regulator and yes, I realise that it is pushing things to charge an AGM battery with it.

My battery regime is that I have a bank of 3 x 110 Ah leisure types which are connected virtually always. They are used for all domestic and starting activities, have been used this way for around 15 years now and have good lives. The starting battery is there for emergency use only and has never been needed. I start the engine with it and charge for an hour or so when I remember but that might be weekly or fortnightly. I suspect that if I did it more often the battery would be fine every time. I might uprate the starter battery to a bigger one but it isn't my top priority.