Hand throttle time.
140 amp vs 80 amp alternators
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Dave 2000
Not all Land Rovers are useless!
I use two batteries, one (start) and the other (Aux), covers all my needs. When parked the parasitic loads (alarm, fridge, ect) are being drawn from both batteries. Within a short while the isolator separates the batteries, all loads now on the aux. When I restart after a couple of days camping for example, the alternator brings the start battery up to voltage and then a short while later brings in the aux but, if I have all the loads baldilocks was talking about as an example and drove to my home say an hour away the aux battery would not be anywhere near charged, despite capable of taking (and actually needing) there simply is not enough amps available from a stock 80 amp unit.
My 150 amp Sequoia brings up the aux very quickly indeed, and going by the NL battery monitor close to 85% charge? I have the papers somewhere but would guess at fitting the larger alternator and batteries around 4 years ago, only recently I replaced both batteries as one was showing a lower charge than the other, this would indicate a pretty good system. There is most definitely a need for an alternator of higher output if your demands (battery or otherwise) can use it.
Maintaining a battery as near to fully charged as possible is the way to go if you expect long life, when camping for more than a night or so, I fit the roof rack and RTT, the rack has a slide out mounted with a 100 watt solar panel (100/12v = 8.3 amps, but again it never works out exactly like that) so this covers my fridge load and LED camp lighting. So in that case the high amp alternator is not needed and a stock unit would be sufficient.
regards
Dave
Dave 2000
Not all Land Rovers are useless!
Difficult this one, a, because of the instruments needed and b, the best method monitors a battery from new collecting data on overall usage.
I use (where possible) FIVE different ways to measure a batteries life/condition.
How old is it is a good start, depending on brand 4 - 5 years is a good start, very hot/cold climates will affect that figure.
If you have access to the cells then a hydrometer is a great tool but, do not just draw up the fluid to check the specific gravity, try drawing, and then pumping back in and repeat a few times. Black sediment coming up will show an ageing battery or even one bad cell in a very young battery.
You can use a voltmeter alone but a battery has to stand for around 12 hours or run the headlamps for about 10 minutes, a bit vague and susceptible to error, and will not show a poor connection between cells.
A digital 'Pass' or 'Fail' meter that passes a current between terminals, not as good as they are cracked up to be.
And my favourite a 100 amp load tester, one of these and access to the cells with a hydrometer is about as good as it gets, you can hit the load button and watch a cell 'bubble and foam' (mind your eyes) that has passed all other tests.
Re alternator, the best and most accurate method is with it put on a load test machine, this will measure output for a given load across a wide rpm range. In the car you can use a voltmeter to check battery terminal voltage with all electrical items switched on, if the alternator holds around 13.8 volts (engine rpm around 1,500 - 2,000) with say your HRW, heater blower, headlights on it shows that to all intents and purposes you are good to go.
regards
Dave
alia176
SILVER Star
I'll never understand this obsession with 140 amp alternators given that batteries can't handle any faster recharge rate! A quality Group 31 as the main battery should serve our 80s fairly well unless you're on of those folks with super duper powerful CB radios with huge gigawatts of transmission power!!! 
Charging system is like a bath tub - if you have a large enough of reservoir (reserve capacity), most heavy loads can be handled easily. Granted, our engine bay wires are 20+ years old so we may need to replace them to get the optimum performance back.
Charging system is like a bath tub - if you have a large enough of reservoir (reserve capacity), most heavy loads can be handled easily. Granted, our engine bay wires are 20+ years old so we may need to replace them to get the optimum performance back.
here's the best I can do for photos.
Agreed 100% I am not interested in a giant alternator because I don't need one. If I get a winch or lots of LED lights, I will go to a dual battery setup. The only reason I am looking at alternator upgrade options right now is because I am rebuilding my engine and I don't wan't to put the crappy aftermarket alt. that the PO installed back in.
I could buy a stock alternator but those are hard to source in Canada. I am interested in the 100amp alternators from a 2005+ Tacoma because they are a very similar size, and I think they may just bolt right in. I am waiting on measurements from someone who has a Tacoma, but it looks promising. Not to mention it can be rewound for more amp output if need be.
I personally went with some die hard platinums. Bought 2 when they were on sale 2 years ago. I finally installed 1 as my main battery ( die hard gold ) since the old one was slowly going. The aux battery on my dual setup is a 5 year old duralast marine which does very well. I run a fridge, and led flood lights for camping and other junk.
After buying the platinums I found out about the special needs charge profile. If I had to do it again I probably would have went with another brand deep cycle conventional from a major chain with a good warranty. The plus side to the platinums is the 4 year warranty.
I'll probably use the extra platinum in the trailer im building so I have more options in mounting it.
After buying the platinums I found out about the special needs charge profile. If I had to do it again I probably would have went with another brand deep cycle conventional from a major chain with a good warranty. The plus side to the platinums is the 4 year warranty.
I'll probably use the extra platinum in the trailer im building so I have more options in mounting it.
I know there has been a lot of talk of Optima batteries as of late, but my neighbor has a 1 year old yellow top that he took off a boat he sold, he's gonna give it to me for free! I'm gonna give it a try. If I start having some problems i'll know it's the battery.
Dave 2000
Not all Land Rovers are useless!
Most informed people go to the larger alternator because they will genuinely use the power. A winch is a great reason to have an extra battery, it is common knowledge that repeatedly dragging a battery below 80% charge can affect it's working life, two batteries in parallel will more or less halve the load extending their lives but, they will need recharging. If you live a few minutes up the road from your last 'pull' both batteries will not receive the amperage they need to fully recharge with the stock unit. It would have to be a serious amount of LED's given they use a very small percentage of the tungsten equivalent, so would not bother in that case alone, well unless you expect to be driving a Christmas Tree. 
Rewinding the alternator (within the same core size) simply moves the idle charge capacity further up the rpm range, and creates more heat to boot. Most put on the smaller pulley to compensate, but if you go for a decent output stock alternator you get, decent amperage at idle, the rated output when it is needed and perhaps more importantly, reliability and longevity. I take my OE 80 amp unit with me as a trail spare, 21 years old and still works perfect and it bolts back in within minutes, plug on the rear still stock, slight bend in the adjuster bar and I am back on the road.
It keeps being mentioned that a battery cannot take a higher charge rate, this is complete bollocks. A battery will take what it needs, and if you do not have the surplus it is calling for after powering everything else then you need to drive for a longer period of time. A battery WILL recover quicker if the amperage is there but, as the charge of the battery rises it needs to be controlled. This is where cheaper regulators/and cheaper 'upgraded' alternators go to pieces, they work their arses off, get hot and burn up. As a youngster with my first car (10 YO), I could not afford a decent battery charger, I used to carry the battery to a car dealer up the road, he would put my completely flat battery on 'fast charge' (for free) it was IIRC simply a 100 + amp battery charger, the battery would be fully charged in around 30 minutes, granted it was hot when carrying it back home, and it gassed enough to rot my shirt but it would take it, of course this is not the way to treat a battery but that was 47 years ago! God am I really that old?
regards
Dave
Rewinding the alternator (within the same core size) simply moves the idle charge capacity further up the rpm range, and creates more heat to boot. Most put on the smaller pulley to compensate, but if you go for a decent output stock alternator you get, decent amperage at idle, the rated output when it is needed and perhaps more importantly, reliability and longevity. I take my OE 80 amp unit with me as a trail spare, 21 years old and still works perfect and it bolts back in within minutes, plug on the rear still stock, slight bend in the adjuster bar and I am back on the road.
It keeps being mentioned that a battery cannot take a higher charge rate, this is complete bollocks. A battery will take what it needs, and if you do not have the surplus it is calling for after powering everything else then you need to drive for a longer period of time. A battery WILL recover quicker if the amperage is there but, as the charge of the battery rises it needs to be controlled. This is where cheaper regulators/and cheaper 'upgraded' alternators go to pieces, they work their arses off, get hot and burn up. As a youngster with my first car (10 YO), I could not afford a decent battery charger, I used to carry the battery to a car dealer up the road, he would put my completely flat battery on 'fast charge' (for free) it was IIRC simply a 100 + amp battery charger, the battery would be fully charged in around 30 minutes, granted it was hot when carrying it back home, and it gassed enough to rot my shirt but it would take it, of course this is not the way to treat a battery but that was 47 years ago! God am I really that old?
regards
Dave
It's my understanding that Johnson Controls bought the rights to Optima Batteries and moved the operation to Mexico in 2009.
I bought two Red Tops for my Dodge diesel coming up on 5 years ago now and havn't had any issues yet.
I think those who report "bad" optima's are a small minority and actually have bad charging systems.
Dave 2000
Not all Land Rovers are useless!
The 'Yellow' tops were called the dual purpose batteries (although there is nothing , and many years ago I used to run them on the LR in my avatar, they were quite frankly brilliant! However when reports of JC moving production plants along with poorer materials, not so good QC and the subsequent (well advertised) failures I moved away. I went with the typical dual purpose battery with a three year guarantee, cheaper and done the job for four years, I replaced them a few weeks (Dec 2015) back with another identical pair. For free you cannot go wrong, and being just a year old it may be fine.
regards
Dave
And factor in the cost of a hi amp charger if you're going with the BIG Odysseys. If they say to use a 30 or 40 amp charger with specific voltages during charge, do it! I learned my lesson.
Cruiserdrew
On the way there
Dave, I guess you are happy with your mod, and that's great. But you are being blinded by wishful thinking. The fact is, batteries can only accept charge so fast at the 14 volts our alternators are regulated at. Go ahead and measure it. You'll find a half discharged normal battery can accept some where in the neighborhood of 30 amps. An AGM battery maybe up to 50 amps. And that only for a few minutes. We can go into the chemistry of why that is if you want.
But the point is, if your battery can only accept 30 amps of current, it doesn't matter if your alternator has the capacity to make 30 amps or 150 amps. The voltage regulator will hold the system voltage in the 14 volt range and so the current beyond your 30 amp charge current simply isn't made and doesn't exist. You are kidding yourself if you think your bigger alternator recharges your battery faster. It's sort of like how your truck runs better after you wash it. It's simply in the mind of the driver. Batteries accept what they accept-but what they accept is way less than even the capacity of the stock alternator. It would be different if you had a whole bank of batteries that in total could absorb more than the capacity of your alternator, but with a normal 2 battery system like ours, that isn't the case.
This is easy to measure. Get one of those clamp on meters that measure current. Wire all your battery grounds into 1 large wire ground and ground that to the battery. Clamp on the meter and start your truck. You'll realize immediately how much current flows and for how long. And if your battery is already 80% full or more, the internal resistance rises and additional charge is accepted more and more slowly, again regardless of the ultimate capacity of your alternator. The only way to increase charge rate, is to raise the voltage of your regulator. But this causes electrolysis of the water in your electrolyte and will ruin the battery in short order. That's what was happening in your younger days with the "fast charge" guy, and by the way, even that was not a full charge, and it was killing your battery each time it was done.
You do need a bigger alternator, if you have high continuous loads. In my ambulance example several posts back, you can see where lights, sirens, radios, ventilators etc, might consume 200 amps or more. But in normal vehicles, that simply is not the case. One other thing. Your alternator plays only a supporting role when winching. If your winch draws 400 amps (fairly typical) and your alternator can supply 150 amps, some of which is being used by the truck, you're working on your battery. Then when you go to charge it up, your battery can only accept charge at it's fundamental rate and we're back to square one.
But the point is, if your battery can only accept 30 amps of current, it doesn't matter if your alternator has the capacity to make 30 amps or 150 amps. The voltage regulator will hold the system voltage in the 14 volt range and so the current beyond your 30 amp charge current simply isn't made and doesn't exist. You are kidding yourself if you think your bigger alternator recharges your battery faster. It's sort of like how your truck runs better after you wash it. It's simply in the mind of the driver. Batteries accept what they accept-but what they accept is way less than even the capacity of the stock alternator. It would be different if you had a whole bank of batteries that in total could absorb more than the capacity of your alternator, but with a normal 2 battery system like ours, that isn't the case.
This is easy to measure. Get one of those clamp on meters that measure current. Wire all your battery grounds into 1 large wire ground and ground that to the battery. Clamp on the meter and start your truck. You'll realize immediately how much current flows and for how long. And if your battery is already 80% full or more, the internal resistance rises and additional charge is accepted more and more slowly, again regardless of the ultimate capacity of your alternator. The only way to increase charge rate, is to raise the voltage of your regulator. But this causes electrolysis of the water in your electrolyte and will ruin the battery in short order. That's what was happening in your younger days with the "fast charge" guy, and by the way, even that was not a full charge, and it was killing your battery each time it was done.
You do need a bigger alternator, if you have high continuous loads. In my ambulance example several posts back, you can see where lights, sirens, radios, ventilators etc, might consume 200 amps or more. But in normal vehicles, that simply is not the case. One other thing. Your alternator plays only a supporting role when winching. If your winch draws 400 amps (fairly typical) and your alternator can supply 150 amps, some of which is being used by the truck, you're working on your battery. Then when you go to charge it up, your battery can only accept charge at it's fundamental rate and we're back to square one.
Group 31 PC-2150s are the largest that will fit in the stock locations. The bigger one lacks the heat range anyway--so 31s it is. Looking at IBS management system; good stuff.
alia176
SILVER Star
Drew brought up some great points and good facts. As I mentioned earlier, your battery is like a bath tub, the larger the tub, the more loads can be supported.
My winch pulls somewhere around 680 amps when I managed to bury myself in the midwest mud (hence I moved to NM!). No alternator can support that kind of a load but a large battery with a high RC can handle this load while the alternator does its best to recharge. However, even if you have a 150 amp alternator, in this example, the winch load will suck down the battery and destroy it ultimately.
I have nothing against dual batt systems, I have one, but I'm sure if they're always warranted.. Long time ago, people were placing these skinny Odyssey batteries in front of their main battery. As you know, there is a lot of space in front of the main battery and if you go with a group 24F (what is recommended by the manual), you can place a skinny battery there. If you kill the main battery, you can jump start yourself!! This follows the KISS principle nicely.
I managed to kill two Diehard Platinum batteries so moved back to blem Interstate lead acid batts for $40/each. As mentioned earlier, these AGM batts requires a charging profile that our 80s can't seem to provide. Lots of posts on the DH Platinum batteries living a short life if you search for them.
I had read nothing about a special charging profile before I bought my diehard platinum 18 months ago. I have beaten it up with some long winch pulls and I have yet to have a problem with it. How much is the life of the AGM supposedly shortened by our charging systems. Seems like Sears would not sell us a battery that we can't charge properly because they simply look in their data bank to choose the correct battery off the shelf.
What automobiles would be able to correctly charge these AGM batteries? Do optimas fall into this category also?
alia176
SILVER Star
Well, if you take a look at a modern battery charger, you'll see that there is a setting for lead acid and one for AGM. Perhaps the newer vehicles with an ECU controlled alternator can better handle an AGM battery? Just a WAG.
Dave 2000
Not all Land Rovers are useless!
I think we are not seeing the wood for the trees here.
What I am stating is, if you do not have the capacity in an alternator to charge the battery because you have twin batteries that are low or flat, it does not matter whether the battery can only take 30 amps or 300 amps, if you do not have that surplus then you will not recharge the battery. You can force a battery by increasing the voltage and most decent alternator do this, you will find when you first start the voltage goes to around 14.6, after a run the voltage drops back, we know this is common knowledge, but you must have a surplus, as I have repeated earlier, demand must be met by supply.
Put it another way, if all your accessories are using 60 amps and your alternator on a good day can supply 80 (remember that is at about 2,500 rpms), and we assume the AGM mentioned wants (or can accept) 50 amps then where are they coming from? The stock alternator does not have the surplus so we are not recharging our batteries effectively. If you purchase a stock alternator that can push out 150 amps @ 2,500 you can reckon on around 70 of them being available at idle or just above, hence my recommendation for a higher output OE unit.
Now, I know you cannot believe all that you read but this guy seems to know his stuff about charging batteries.
Car Battery Myths & Facts: Car Battery Myths (Part 2 of 4)
The first few paragraphs seem to be all we need here.
He also goes waaaaay deep from here, seems to read 4 of 4? Car Battery Myths & Facts
regards
Dave
What I am stating is, if you do not have the capacity in an alternator to charge the battery because you have twin batteries that are low or flat, it does not matter whether the battery can only take 30 amps or 300 amps, if you do not have that surplus then you will not recharge the battery. You can force a battery by increasing the voltage and most decent alternator do this, you will find when you first start the voltage goes to around 14.6, after a run the voltage drops back, we know this is common knowledge, but you must have a surplus, as I have repeated earlier, demand must be met by supply.
Put it another way, if all your accessories are using 60 amps and your alternator on a good day can supply 80 (remember that is at about 2,500 rpms), and we assume the AGM mentioned wants (or can accept) 50 amps then where are they coming from? The stock alternator does not have the surplus so we are not recharging our batteries effectively. If you purchase a stock alternator that can push out 150 amps @ 2,500 you can reckon on around 70 of them being available at idle or just above, hence my recommendation for a higher output OE unit.
Now, I know you cannot believe all that you read but this guy seems to know his stuff about charging batteries.
Car Battery Myths & Facts: Car Battery Myths (Part 2 of 4)
The first few paragraphs seem to be all we need here.
He also goes waaaaay deep from here, seems to read 4 of 4? Car Battery Myths & Facts
regards
Dave
Here's what my gauge reads going down the road.
Dave 2000
Not all Land Rovers are useless!
Although the gauges on the 80 are a bit hit and miss that looks fine to me. I have recalibrated all my gauges in the past to reflect what is really happening under the bonnet.
EDIT: And what is in the fuel tank as well.
regards
Dave
EDIT: And what is in the fuel tank as well.
regards
Dave
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