Reccomended Battery

[firemannotsam]

Hi guys, I am looking for some advice from those that know about batteries and electrickery stuff (not my strongpoint).

My 1999 Disco 1 V8 has just a standard battery fitted but since I have fitted a lot more electrical stuff I think I need a more powerfull battery to supply all the stuff.

I have fitted twin 13" Kenlowes (set to run on full speed(boost) when needed as I think cooling it down faster is better)

Light bar on roof with four spots

Inverter to run laptop etc ( only really used when vehicle is running but wired direct )

coolbox Powered through ciggie lighter circuit

It has aircon fitted so obviously the fans will run once the engine warms up causing more draw.

It let me down the other day!

I was stuck in traffic in the heat on the motorway,

I had coolbox running,

Laptop was being used by passenger through inverter,

Normal lights were on as I had turned them on as had just been in tunnel,

Kenlowes running quite a bit due to stationary for ages

Aircon fans running

Aircon being used

Satnav plugged in

phone charging

Radio on.

Car was running fine, pulled into services turned off went bought drink etc came back and no start!!!

Unplugged everything/ turned everything off - inverter had already been turned off when stoped. Still no start!!!

Noticed that as soon as the ignition was turned on that the engine was obviously still hot enough to need extra cooling as the Kenlowes and aircon fans were firing up.

Decided to stop those using electricity when trying to start by pulling fuses for all of them.

Engine turned slowly and started yippee!!! replaced fuses and cracked on no problem.

Sorry for the long winded explanation just wanted to be clear what happened.

It has not had a problem the last few days and never gave me a problem before - the battery is healthy and the alternator is ok too, just think it was too much for the battery to handle?

I dont want to go down the second battery route for two reasons;

1. I very rarely will be in that situation were I am using everything to that extent and don't think my usage justifies the expense of twin batteries.

2. I have very little room under the bonnet as I have lots of lpg gubbins behind the passenger headlight where it would go easiest and the innerwing on that side is where I have put the kenlowe electrics etc - the only place really is where the washer bottle is that I can see.

I think replacing the original spec battery with something more powerfull would solve the problem, I have been looking at the Optima range of batteries as they have got good press generally, athough any other suggestions would be welcome.

Would I be best going for a "red top" starting type or would I be bet going for the "yellow top" starting and deep cycle type to cope with the times when I am using lots of stuff (especially the inverter) ?

Any help advice would be appreciated

Thanks in advance

Firemannotsam

[kindwarf]

Hi guys, I am looking for some advice from those that know about batteries and electrickery stuff (not my strongpoint).

My 1999 Disco 1 V8 has just a standard battery fitted but since I have fitted a lot more electrical stuff I think I need a more powerfull battery to supply all the stuff.

I have fitted twin 13" Kenlowes (set to run on full speed(boost) when needed as I think cooling it down faster is better)

Light bar on roof with four spots

Inverter to run laptop etc ( only really used when vehicle is running but wired direct )

coolbox Powered through ciggie lighter circuit

It has aircon fitted so obviously the fans will run once the engine warms up causing more draw.

It let me down the other day!

I was stuck in traffic in the heat on the motorway,

I had coolbox running,

Laptop was being used by passenger through inverter,

Normal lights were on as I had turned them on as had just been in tunnel,

Kenlowes running quite a bit due to stationary for ages

Aircon fans running

Aircon being used

Satnav plugged in

phone charging

Radio on.

Car was running fine, pulled into services turned off went bought drink etc came back and no start!!!

Unplugged everything/ turned everything off - inverter had already been turned off when stoped. Still no start!!!

Noticed that as soon as the ignition was turned on that the engine was obviously still hot enough to need extra cooling as the Kenlowes and aircon fans were firing up.

Decided to stop those using electricity when trying to start by pulling fuses for all of them.

Engine turned slowly and started yippee!!! replaced fuses and cracked on no problem.

Sorry for the long winded explanation just wanted to be clear what happened.

It has not had a problem the last few days and never gave me a problem before - the battery is healthy and the alternator is ok too, just think it was too much for the battery to handle?

I dont want to go down the second battery route for two reasons;

1. I very rarely will be in that situation were I am using everything to that extent and don't think my usage justifies the expense of twin batteries.

2. I have very little room under the bonnet as I have lots of lpg gubbins behind the passenger headlight where it would go easiest and the innerwing on that side is where I have put the kenlowe electrics etc - the only place really is where the washer bottle is that I can see.

I think replacing the original spec battery with something more powerfull would solve the problem, I have been looking at the Optima range of batteries as they have got good press generally, athough any other suggestions would be welcome.

Would I be best going for a "red top" starting type or would I be bet going for the "yellow top" starting and deep cycle type to cope with the times when I am using lots of stuff (especially the inverter) ?

Any help advice would be appreciated

Thanks in advance

Firemannotsam

I would get a higher output alternator.

[pinny]

I would get a higher output alternator.

hi i have 4x 100w spots on roof plus a 4 rotator light bar 4x55w bulbs with all these on including head lights its still maintaining 12.8 v /13.2 at tickover i have a 100amp alternator fited but no aircon and only one battery maybe your alternator on the way out chris

[Les Henson]

I would say alternator problem too. A 100-amp item would be good.

Les.

[BogMonster]

Yep bigger alternator - if it is only just (or not quite) keeping up with the demand then the battery size is irrelevant it will still go flat might just take a bit longer!

[firemannotsam]

hi i have 4x 100w spots on roof plus a 4 rotator light bar 4x55w bulbs with all these on including head lights its still maintaining 12.8 v /13.2 at tickover i have a 100amp alternator fited but no aircon and only one battery maybe your alternator on the way out chris

Thanks for your replies guys, As I said alternator is fine the two big draws on the batteries above the normal standard vehicle usage is the inverter and the Twin Kenlowes on full speed wich both have a big draw on the battery( although normally only for short periods) and are above the normal usage levels the original battery was designed for.

My alternator is the 100A standard

Lights and aircon etc are all normal levels as it was fitted with these as standard I just think I was taking out more than I was putting into the system and that possibly a more powerfull battery possibly with a deepcycle capability would give enough reserve to cope with these extra demands on the rare occasions I put the extra demand on the system without going for the second battery option to run things like the inverter/coolbox etc

Hope this makes sense.

Im sure some techy person will come on with figures etc to back up or more likely discredit my opinion!

I will later today dig out my multimeter and check alternator output and battery again, I will try to recreate similar circumstances by turning on lots of stuff and getting it warm enough to turn on the kenlowes etc but it is difficult to recreate an hour in hot traffic with everything running to check how much I am running the system down by.

firemannotsam

[LandyManLuke]

twin 13" Kenlowes - guess at 35A for the two

Light bar on roof with four spots - not on at the time?

Inverter to run laptop - guessing at a 600w inverter, 50A

coolbox - 5 to 10A at a guess

aircon fans - 30A guess, inc condensor and evaporator fans.

driving lights - 55 + 55 +5 +5 +5 +5 = 130W = 11A

Satnav plugged in = ~1A

phone charging= inc in above

Radio on. 5 to 10 A

Adding that lot up, you were drawing 142 A ish.

Assuming the alternator is tip-top, and actually producing 100A (bearing in mind it would need to be at approx 2500 RPM to do so, not tickover/traffic crawling) , that means you need 42A from the battery, whilst everything's running.

The standard battery is approx 70AH, that means after 1.6 Hrs (1 Hr 36 mins) the battery will be flat, and no good for starting. once a battery gets below 10.5v it's sustaining damage.

A bigger battery isn't going to do much, apart from buy you more time. A bigger alternator would mean you wouldn't get into difficulty in the first place, or at least to a lesser extent.

The numbers above are obviously estimates only, you may well only have a 350W inverter for example, but the logic is sound. A slow speed alternator will not produce that much current, and you have a large draw on the system with everything running.

HTH

Luke

[firemannotsam]

Hi guys, just been out to the car to run some basic checks with my multimeter.

all measurements across the battery terminals.

Engine/ignition off. 12.48V

Engine up to temp and at idle. 13.98 V

Idle with aircon on (fans running) blower on max. coolbox plugged in, inverter on, lights on full beam, 4 spots on roof on, radio/phonecharger/satnav on. 12.5V

Idle with all of the above + manually turned both Kenlowes on to full speed. 11.6V

do these numbers look right?

The alternator is the Lucas A127 100A

Am I simply using more than I am producing when everything is on at once.

Im sure someone will correct me!

Would a more powerfull battery have more reserve to cope with the short periods when everything is running full tilt and more starting power even after it has been used hard for a bit?

Is there a more powerfull alternator I could fit?

Without any modifications or silly money spent.

Thanks again for your time and expertise guys.

[LandyManLuke]

Engine/ignition off. 12.48V - OK

Engine up to temp and at idle. 13.98 V - OK, at 2k rpm would have been a better reading

Idle with stuff on 12.5V - Starting to use more than you've got

Idle with all of the above + both Kenlowes , 11.6V - on the way to a flat battery, as per my maths above.

Am I simply using more than I am producing when everything is on at once. - YUP!

Would a more powerfull battery have more reserve to cope with the short periods when everything is running full tilt and more starting power even after it has been used hard for a bit?

Battery "power" is measured primarily in 'AH' Ampere-hours - how long you can draw a certain current, and 'CCA' or Cold Cranking Amps - the umph a full battery can kick out to start an engine.

A larger AH capacity will buy you time when you're drawing more than the alternator is giving. More CCAs will turn the over engine easier/quicker.

There are bigger alternators out there, you would need to upgrade the wiring for a higher output alternator.

Be warned though, no alternator will produce its maximum current if it's not spinning fast enough. You could fit a smaller pulley if you spend a lot of time at slow speeds.

[firemannotsam]

Adding that lot up, you were drawing 142 A ish.

Assuming the alternator is tip-top, and actually producing 100A (bearing in mind it would need to be at approx 2500 RPM to do so, not tickover/traffic crawling) , that means you need 42A from the battery, whilst everything's running.

The standard battery is approx 70AH, that means after 1.6 Hrs (1 Hr 36 mins) the battery will be flat, and no good for starting. once a battery gets below 10.5v it's sustaining damage.

A bigger battery isn't going to do much, apart from buy you more time. A bigger alternator would mean you wouldn't get into difficulty in the first place, or at least to a lesser extent.

The numbers above are obviously estimates only, you may well only have a 350W inverter for example, but the logic is sound. A slow speed alternator will not produce that much current, and you have a large draw on the system with everything running.

HTH

Luke

Thanks for the figures luke, I think the Kenlowes are 30A and the inverter is 300W I think but the total would still be over what I need when the Kenlowes are running full tilt.

I posted some test results just a few mins ago so which you may have read which makes me think that genearally its the kenlowes and inverter tipping it over the edge.

The Battery is a 65A (so it says on the tin!)

Is it worth the expense of a new alternator to cover the very rare occaisions when the Kenlowes are working hard and the inverter is in use or as the battery is a few years old anyway replacing it with a much more powerfull which can cope with the short periods of extra demands.?

My passenger(daughter) was bored sand using my laptop,

inverter is rarely used -

don't use the aircon much (my passenger wanted it on - I prefer the window open) and rarely is it hot enough to warrant the Kenlowes getting such hard use.

Obviously best option is belt and braces i.e. both but chuck enough money into the tank of the Disco!!

Thanks for your time.

firemannotsam

[firemannotsam]

Thanks for the figures Luke, looks like you know what you are up to with electrics I appreciate your time taken to explain it to me.

I think the Kenlowes are 30A and the inverter is 300W I think but the total would still be over what I produce when the Kenlowes are running full tilt.

I posted some test results just a few mins ago so which you may have read which makes me think that genearally its the kenlowes and inverter tipping it over the edge.

The Battery is a 65A (so it says on the tin!)

Is it worth the expense of a new alternator to cover the very rare occaisions when the Kenlowes are working hard and the inverter is in use or as the battery is a few years old anyway replacing it with a much more powerfull which can cope with the short periods of extra demands.?

My passenger(daughter) was bored sand using my laptop,

inverter is rarely used -

don't use the aircon much (my passenger wanted it on - I prefer the window open) and rarely is it hot enough to warrant the Kenlowes getting such hard use.

Obviously best option is belt and braces i.e. both but already chuck enough money into the tank of the Disco!!

Based on what you have said and the fact that it will involve a fair bit of money to get an alternator that can cope fully under the worst case scenario (which is very rare) and modify the wiring etc, I am leaning towards the more powerfull battery option thinking that enough power to cope with the short periods of over use will usually be well compensated by good charging in between periods when the Kenlowes are being used, and not putting high demands such as the inverter on the system whilst the kenlowes are working hard and the vehicle is at low speed/ stuck in traffic.

In two years this is the only time it seems to have failed to cope and I was stuck in traffic for well over an hour in stop start traffic on a very warm day.

would something like an optima Red top be suitible or is there another battery that you would reccommend I fit - Must fit in the standard battery box.

Thanks for your time.

firemannotsam

[LandyManLuke]

Personally, I'd firstly accept that the simplest solution is to understand the limitations of the system, and work with/around them.

For example, if you'd turned everything off for the 5 - 10 minutes you were driving down the slip road, and parking up, the battery probably would have started the engine fine.

I don't see any specific need for a brand name battery, you don't specifically need AGM or leisure battery technology, either IMHO.

I would replace the battery with the 'biggest' (physically, and electrically - AH and CCA) standard lead acid battery you can fit. You could fit a voltmeter (not a rip-off 'show off' one, just a decent voltmeter) so in future you would be aware that you needed to recharge the battery etc.

[firemannotsam]

Thanks again Luke I think I will pop down to somewhere like Halfords and look at what they have that will fit in my battery box and has the highest AH and CCA possible.

Might get some looks measuring batteries but at least I know I can physically see the battery. Might be a bit cheaper than something like an optima.

The voltmeter is a good idea think I will get one of them - at least I know when the battery is getting abused and can shut stuff off to keep it in good nick for starting.

Thanks again for your time and info Luke.

Lindley

[LandyManLuke]

I'd forget Halfords, hit yellow pages/yell.com and look for a battery stockist, or try your local agri motorfactors, they'll likely have larger and cheaper batteries than Halfrauds!!

[Rodewaryer]

I'm interested in the High output alternator route as well. I have already done the yellow top Optima battery on my Disco 1. This is a very good battery, I just think under certain conditions with AC on (I live in the desert) and a lot of lamps etc that the HO Alternator would be the ticket. I have done this to my Focus already, I installed the yellow top Optima battery, upgraded the ground cables with a kit (that also adds a few), and then I replaced the 105 amp alternator with a 180 amp unit. It's expensive stuff however but now that it's all done, I can cook anything within a couple hundred yards at night (with the exception of other vehicles of course) and have absolutely no worries how many accessories are running.

I'm going to contact the place that did my Focus unit (in the central USA) and see what's available for the Discovery.

http://www.highoutputalternator.com/online-catalog.aspx

They do have a listing for the Series 1 Disco but require an email query for availability and price.

[Reng]

The measurement of 12.5 volts with the ignition off is the one to worry about. The voltage should be about 13.5V for a fully charged battery. At 12.5 volts you are close to the battery being flat and it definitely wont run your electrics for to long even with the engine running and charging. With the engine running you should ideally measure 14+ volts to be charging the battery after you have all the other electrics running Have your battery and alternator checked before you spend money.

[JimAttrill]

Strange, I have 4 cars and 5 batteries and they all read 12.5 or so at the battery with no load.

[sotal]

Strange, I have 4 cars and 5 batteries and they all read 12.5 or so at the battery with no load.

Snap 5 batteries here which all read approx 12.5 with no load, between 13.5 and 13.9 with the engine running, none of them get above 14v.

Reng - I'd be worried about frying my battery at the voltages you talk about.

A 65 AH 12 V battery should run 65A for one hour before the battery gets to a level where it's too low. So the coolbox at 10A or so shouldn't affect anything for a good few hours.

[firemannotsam]

Hi guys thanks for the replies, much apreciate people with more knowledge than me.

Reng thanks for your reply but think you may have your figures a bit mixed up, I agree with the others that a charged battery with no load should be 12.5ishV

I agree that it should be 14V+ when running with no load. I got a reading of 13.98V considering Its an EFI with lots of electrics running I think this is close enough at Idle.

If I had revved the engine I am sure the readings would have incresed even with everything turned on, but I was simulating stuck in traffic so Idle measurements were what I wanted.

For the rare times I will be overloading the system I think the expense of a new alternator and wiring is a waste but a shiny new battery with a bit more guts than the

60A 280CCA bosch one fitted at the moment that has been on there for at least the 2 years I have had the Disco and probbably alot more will give me a bit of reserve if I need it.

I will also get myself a voltmeter to fit to the dash so I can monitor the battery/alternator and if I am starting to use to much I can turn stuff off.

So last couple of questions guys, anyone Know of a nice easy to read voltmeter that I can just place/stick to the dash area for sensible money or am I looking at one of those pods from car tuning places?

Is there a nice easy to get at grommet on the bulkhead drivers side that comes out somewhere easy to get at that I can run the feed for it through without lots of hassle - had a quick look but the only one I see looks like it may be difficult to find the other end!

Thanks again for your replies guys

Lindley

[BogMonster]

The measurement of 12.5 volts with the ignition off is the one to worry about. The voltage should be about 13.5V for a fully charged battery. At 12.5 volts you are close to the battery being flat and it definitely wont run your electrics for to long even with the engine running and charging. With the engine running you should ideally measure 14+ volts to be charging the battery after you have all the other electrics running Have your battery and alternator checked before you spend money.

Not in my experience either!

A fully charged battery, off load and off charge and given time to settle, is usually about 12.6-12.7 volts. 12.5 might be a little discharged but is OK, less than about 12.4 is time to get the charger out. The highest I have ever seen on a brand new fully charged battery is about 12.85v. You will get 13.5v out of a battery when the engine has been running recently but if left to settle (i.e. overnight) this will drop back.

With the alternator running and normal engine revs and load (i.e. not at idle or with everything electrical on) the voltage should be 14.2 to 14.4, a bit less than that under high load or at idle but if the voltage with the engine running at operating revs is less than about 13.5 you are definitely heading into a supply and demand problem.