I had read other posts about the ignition barrel, but mine musn't be worn as the key can only be removed in the normal position.

 

Hi QinteQ/leedsman

Just found the photos of the 3 way switch, sorry took so long.

Switch is from Maplins, 2 or 3 pounds I think, its an "FH05F".

I have left it on the high charge for last couple of months and don't think its overcharging. I think its under capacity because it was undercharged on the vehicle for 18 months, might try your trick of trickle charging for a couple of weeks.

 

Keep the battery or batteries on float-charge of 13.8volt permanently if possible, using the left-hand cigar lighter socket; after a few weeks/a month or two, the hardcrystal sulphation should have returned to amorphous and then to lead dioxide consequently. So you could be back to the ampere-hours stated on the battery. Keeping the battery(s) on permanent float-charge keeps it near to the desireable 100% charge which will result in a very long service life, and enthusiastic cranking when it's cold. The side issue of parasitic drain then becomes irrelevant.
The only problem with the above is if you can't get mains electricity to the parked vehicle. This may be a problem for me if I move to a flat where the parking spot is too far away. I have a plan for this; I shall put a 30watt solar panel collector on the GV's roof, to be wired through a 13.8volt regulator*. The size of the collector is because in winter when you really DO want a properly charged battery, there is the problem of no direct sunlight (diffused daylight), the sunlight such as you get being at a steep angle due to its limited arc in the sky, and the shorter daylight hours. The panels I have at 5watt total are only just good enough in bright overhead summer sunlight to make 13volt on the battery. No chance of keeping the voltage up in winter with those.

Leedsman.
* A common 7812 12volt regulator can very easily be made to produce 13.8volt by a cheap trick I have. A 30watt panel may need an external blocking diode. I would use a shottky diode as these only drop .3volt.

 

I don’t understand why you had so much trouble with batteries. (I have a 1994 GC with 3.3L and 120A alternator, works fine.) Perhaps because you have a diesel engine and can’t plug in a block heater or trickle charger – and you have extra parasitic drain.

A temperature sensor is desirable if charging at high voltage to avoid deteriorating the battery. Doubly so if using the AGM/VRSLA technology (which the spiral wound type probably is) because of the limited amount of electrolyte. (AGM/VRSLA technology provides superior cold weather performance to flooded lead acid technology. Sounds to me that AGM/VRSLA technology is what you need. The Optima is a premium product, hopefully reliable – some AGM/VRSLA designs were not. (A version from Exide leaked from the terminals, a sign of poorly thought out design - AGM/VRSLA can develop pressure up to a relief valve setting, thus sealing of the terminal through the top of the case must be robust, what works in a flooded design may not be adequate.)

 

1). The separator material between the plates makes no electrical difference to the lead-acid battery. But alloying the lead with calcium does. (Antimony is no longer used). A calcium lead-acid battery means one plate (the lead dioxide paste positive plate) is alloyed, and a calcium-calcium battery means BOTH plates are alloyed, ie. the spongy negative in a starter battery. The chief advantage of this technology is a big reduction in self-discharge, something all batteries suffer from to some degree or other. Calcium-calcium lead acids require a slightly higher float and end-of-charge voltage. (13.9 and 15volt respectively).
2) The separator material used nowadays is to ensure minimum spillage of electrolyte (dilute sulphuric acid, about one third acid, two thirds water. This ratio changes considerably as the battery is charged and discharged). Although the battery manufacturers won't tell us ALL they put in their batteries, separator materials include
a) Absorbent glass mat. Two grades of mat are used together, one with a hole structure about 6microns, one much smaller. This ensures a so-called hydrogen pathway through it to enable recombination of H2 and O2 back to water from modest gassing. The main advantage is that there is very little electrolyte "loose" as 'twere, and the structure is "sandwiched" so the lead-dioxide paste can't fall out of the positive grid. The main disadvantage is acid stratification, a serious flaw acting against battery service life. The following battery type also suffers from this. Stratification gradually gets worse over time as every charge/discharge cycle increases the effect, ending up with a major section of the plates trying to run on near-plain water. This problem was absent on the old wet battery as the electrolyte could slosh about freely, and in a car, did just that.
b) A polymer holding the electrolyte, making the so-called "jelly" battery. Because the jelly is slightly sloppy, the hydrogen pathway can establish itself through it, thusly achieving recombination back to water from modest gassing. Most jelly batteries are "spiral-wound" as many of the old victorian lead-acids were.
c) Some batteries use an undisclosed separator, some batteries are still "wet" although described as 'non-spill' (but they do if you upend them, I know, I've tried it during a de-stratification technique I used). If the electrolyte is free to move around a little, stratification is much less likely. Some are described as "sealed" using a pressure-ventilation system or "valve-regulated". None of the modern batteries need topping up with de-ionized water, indeed can't be -- there are no filler caps.

Finally, as regards charging a lead acid, be guided by the particular manufacturer, easy one this, just Google the battery type number. Ordinary car users don't ever think about charging a lead-acid, but adhering to the requirements is vital for its service-life. Far more batteries in use on cars as starter batteries "die" as a result of UNDERCHARGING, -- not overcharging.This undercharging has come from parasitic electrical loading 24/7 on batteries that are not designed for it or capable of dealing with it. So a car only used once a week and having a 2-year old undercharged sulphated battery one day will refuse to engage the solenoid starter switch, giving the dreaded "no-start" heavy "click". You have only to read this website and the internet to see how widespread is this problem.
KEEP YOUR BATTERY ON PERMANENT FLOAT-CHARGE if you are an infrequent user, and if it is humanly possible*. Small plug-top chargers are available that give out a suitable lead-acid float charge for a car battery. I know they do because I have one. A permanent float charge will NOT, repeat NOT damage your battery, it will only extend the battery's service life to it's full extent and more to the point -- GET YOU STARTED!

Leedsman.

*Of course if you can't get mains/powerline power to your car whilst it's asleep, you are not completely stuffed. There is the solar panel route. Much on this website about these panels and their use for charging a starter battery.

 

EDIT : 15th Feb 2016 - This ButtonMOD started by Leedsman is carried on in this post

 

Hi, the 2.5/2.8 diesel has a battery capacity far too small especially for short journeys whereas a petrol car needs a smaller battery.

And again for this type of car with all its electrical goodies needs a bigger battery.

So combine:
Undersized battery
Low floating charge
Huge electrical demands
Starting issues (such as dodgy fuel pressure relief valve or filtration)
And various issues while engine off (wipers,switches,alarms drains)


And you have a recipe for disaster to drain the battery or not charge it enough for the next start.

Raise and maintain a higher floating charge i.e. 14.5V or so and you are onto a winner, I am running it for 6 weeks or so now but let it pass one winter without an issue and I will be 100% confident

 

I did a further mod and changed the the 33K Ω @ 1/2 watt to 22K Ω @ 1/2 watt keeps it under the 4.6[ish] [although I'm sure it would be safe a little higher]. I did get the extra .3's @ 14.4+ I was aiming for. This will better recover the winter loss more quickly. Of course in the summer the ALT output will be limited by the lower battery replenishment needs. That thread is here and I can confirm that I had 14.5-6V over the winter and its now an average of 14.3-4V summer.

EDIT : I've now run this setup for more than a year right through last years winter. My summer charge rate is 14.2/3 volts and my winter charge rate was an average of 14.5+ volts - the point being the winter draw [and [URL="http://www.chryslerforum.co.uk/topic/1817-battery-drain/?p=7690"]battery pathology] is automatically compensated for .. .. .. compared to summer use. Best of luck.

Chrysler alternators do not use an internal regulator. As is well known to this forum users I'm ecumenical about the batteryMOD. A pulse width modulated signal generated by the PCM, is used to switch the current to the rotor’s field coils on and off, how hot or cold the battery is is as we know precisely the button thermo-couple under the GVCRD. Gonzo says:

Charge Mode – Bumps up the charging voltage when the battery is low or when there are unusually high loads on the system.
Fuel Economy Mode – Lowers charging output to just under 13 volts to reduce the alternator’s load on the engine.
Voltage Reduction Mode – Reduces charging output when the battery is fully charged and electrical loads are low.
Start Up Mode – Momentarily fixes charging output at a steady 14.5 volts for 30 seconds following an engine start.
Windshield De-ice Mode – Increases charging output when the defrosters are on.
Battery Sulfation Mode – Increases charging voltage after 45 minutes if the battery is low.

I confess to not knowing the logic on the alternator controlled so many things. This is why I dislike the idea of BCM / PCM / control and battery drain. Ditto 'red top' batteries AGM and second batteries in the UKCRD.

 

I modified mine and set it to 14.2V two years ago, works absolutely fine and I've never had a flat battery since

 

Without going back through what I said earlier, I note:
- North American Caravans of that vintage can fit a size 27 battery, but I recommend a shield over the top (I used plastic lid off a casserole dish sold here), and preferably having + terminal on left for more clearance, as extra precautions. Terminal orientation may be defined by a suffix, such as 27F, or absence of one in the other orientation.
- GGM/VRSLA technology is great in cold weather, equals NiCad, but is prone to overcharging due small amount of electrolyte
- larger alternator is something to consider.


Original behaviour of your vehicle seems odd, perhaps the computer's temperature sensor is not accurate. (As far as I've been able to find, NA vehicles use a sensor in the PCM that sticks out into the intake airflow, primary purpose is fuel mixture control but may well be used for the battery. My two vehicles run at 14.0, as did a 1985 GM car, the only time I've seen less is when battery is depleted so pulling down the alternator as it can't supply enough current for battery demand. But I haven't rested in hot weather (haven't noticed any difference on dash gage though).