AMB

HoSS - as I said "Whether unacceptably low is anyone's guess". If overbouyant as you say, then type of fuel should not make any obvious difference to the float level. For me the answer lies in the fact that LR found it necessary to have different senders.

LR wouldn't have made a change unless they needed to. I'd assume that the electrical side and associated length of float arm would be identical. Diesel is about 10% denser than petrol so probably a different float. For the float arm to sit at the same angle for the same fuel level, the diesel float would either need to be 10% heavier or a smaller float than the petrol one. So I'd guess that fitting a diesel sender to a petrol tank would make it read low. Whether unacceptably low is anyone's guess.

Possibly because a lot of automotive and accessory manufacturers are either not particularly good at electrics, design down to a price or write manuals for joe public - witness LR design! or Lucas in general. My point was more to do with earth loops/offsets causing issues with lower power electronics and instrumentation than with battery cable failure.

As another professional engineer, I agree entirely.

You have to wonder whether the reward is worth the effort and consequences if caught. I'm reminded of a couple of stories told by an old workmate of mine. He was out of work for a time and had taken a job at Gatwick patrolling car parks, boost starting cars etc. He told the story of an E-type where the engine had been stolen sometime during a two week holiday. This was before the advent of CCTV everywhere and the patrols averaged about an hour between visits. The local Jaguar dealership reckoned that it was a two day job in a properly equipped workshop and couldn't be done without ramps and special tools. If the police had caught them they would have been offered a job. He also told of fuel theft during fuel shortages of the 70's. Thieves were cutting through the perimeter fence and using an aircraft pump to empty fuel tanks. Equipped that way they could flush a tank in seconds. Unfortunately, the suction was so strong that it flattened some tanks - leaving owners wondering why their cars showed all the symptoms of no petrol whilst the fuel gauge read full.

I agree with Les. Diesel doesn't tend to go off, but can get contaminated. Unless the tank is almost completely full, you will almost certainly have accumulated water through expansion/contraction and resultant condensation build up. If there is water in the fuel, you can get fungal/bacterial growth in the water/fuel interface which forms a black slime. In mild cases you can treat with a biocide (available from marine suppliers) and a few frequent filter changes. Some diesel injector treatments actually include a mild biocide. If severe, then drain etc is required.

Mine was(is) leaking from the top fuel take-off on my 300 110 CSW. Only happens when I top right up or to first click in hot weather. Tank is starting to corrode around the seam so intend to replace over the summer, before I'm forced to with snow and ice on the ground.

http://www.landroverworkshop.com/parts/RTC6065

I had problems with my main beam - would not switch on, but would flash via the dip/main stalk. It turned out to be bent contacts on the dip/main stalk. The contacts are on the left hand side of the column and completely open. Some careful bending with some fine nose pliers and the system worked again.

Assuming that your voltmeter is sensitive enough to note any changes after battery smoothing, I'd tend to agree with the broken/corroded wire diagnosis. To reduce battery smoothing effects on the reading rig your voltmeter directly across the alternator. As to cooling air direction in alternators, I wonder whether it's that clear a decision in practice. You want the most sensitive part of the component receiving best cooling, even if that is at the expense of other items. In an alternator the most sensitive part is the rectifier, usually mounted at the rear of the alternator. Windings etc are rated for much higher temperatures than diodes. Question for a designer should be whether using forced air passing through heated windings provides a lower temperature environment for the rectifier than pulling engine bay air past the diodes first. I don't know the answer, but my first instinct would be to pull air past the rectifier first then look at alternatives.

Not doubting that's what you were told, but that sounds and smells like bullsh**. Typical of government minor official - caught out without a definitive answer and yet needed to sound as if he knew. I defy anyone to tell the diference between LED and tungsten lighting when fitted behind a red tail/stop light or amber indicator filter. The whole point of a filter is to only let the required colour light out. You can even buy LED bulbs of equivalent colour temperature to tungsten (2700K) to fit behind clear lenses if you are prepared to look around. PS - no E marking on the factory fitted tail light of my Skoda.

I may be mistaken, but believe that only the headlights and other lights with a focussed beam are E-marked or required to be E-marked. Certainly a quick check of my spare bulb set only showed the headlamp Halogens carrying an E-mark. If that is the general case, then under construction and use regulations, LEDs can be used as bulb replacements except in headlamps. The only issue may be light output, though the construction and use regulations used to specify maximum wattage for tail and brake lights rather than lumens. If I feel particularly nerdy tomorrow, I may take a tail light bulb out of the Skoda tomorrow and inspect it - it has the original manufacturers fitted bulbs in all the lights.

Boydie - I was at Nottingham Uni, 1968-72. Electrical & Electronic Eng. You?

When were you at Nottingham? Fond memories of a similar Austin Westminster

When charging the system, the RedArc should NOT switch on until the input (main battery) volts reaches 13.2v. Having switched on it should stay connected until the input voltage drops below 12.7 volts. That prevents the RedArc switching on/off rapidly and should ensure that the main battery is maintained at a high state of charge. I was suggesting that the RedArc needs to be close to the main battery in electrical terms and, rather than route the alternator feed to main battery then RedArc that the RedArc be used as the input to the system

Bowie69 is obviously thinking along the same lines as me. You are apparently losing 1 volt across what should be a very short length of high current rated cable between the main battery and the RedArc. To put that into context I measured just over 1.4 volts drop between battery and headlamps for a nominal current of 10A, a comparatively lightweight cable and a longish run. If you had a similar order of cable drop/metre between alternator and main battery it would be unlikely to charge. I haven't checked the formula for accuracy, but RedArc suggest that voltage drop across a cable equals length (in metres) times current (in Amps) times 0.017 divided by Cross sectional area of copper in square millimetres. That drop will increase with temperature, including self heating due to current carried. Using that formula, assuming 1m of 8 square mm cross section cable between Main Battery and RedArc input at 60A would give a voltage drop of 0.13volts plus connector drop. Why the voltage drop? Measurement error? - are you using the same reference earth for all measurements? The cables may be OK, ditto the earth connection, but what about the crimped connectors? (Note, if done properly crimped connections should be lower impedance than soldered). I think that your best option may be to run the alternator connection directly to the RedArc input, then to the main battery. The RedArc needs to be mounted as close to the main battery as possible, using heavy duty cable and the same earth/negative terminal as the main battery. That arrangement should ensure that the RedArc accurately measures the main battery voltage and therefore gives maximum charging time for the auxiliary. Routing the alternator feed to the main battery via the RedArc input terminal should (very slightly) increase the voltage available to charge the auxiliary. If I've interpreted the RedArc spec correctly it has 0.5 volts of hysteresis ie needs to exceed 13.2 volts for 5 seconds in order to switch the auxiliary battery into circuit, then maintains connection until the main battery drops below 12.7 volts. That does imply a short period of battery energy sharing after the engine has shut off over and above the stated 10s switch off delay. RedArc have obviously seen some of the problems you've experienced, in that they recommend that "start and auxiliary batteries be of similar chemical characteristics when charging via the Smart Start® SBI". When using this in anger (ie when the fridge cuts out after the third day) how many hours charging time do you estimate that the system may have?

As I said - haven't seen a blown alternator on switching for some years. They used to be fitted with rectifier stacks rated at only 16v and could be tender as a result. They usually failed before the spike hit the radio - not much else in the way of electronics in those days. I had access to high power diodes and a decent press through my job and have repaired a few in my time

Boydie - Which RedArc version do you have? Looks like some models have an override wire which may help. However, like cackshifter I'm a little puzzled. Why is there 1.3v drop between the main battery and the RedArc input? Volts drop implies current and/or resistance. If you have 14.5v at the main battery, standard (150A?) wiring to the RedArc and 1.3v drop across that wire then that implies a fair current going somewhere - or a little current across a big resistance. 13.2v at the RedArc may mean that it has not switched on. Once switched on it ought to hold, even if the main battery feed drops to just above 12.7v You could try artificially increasing the voltage at the RedArc input by routing the alternator positive first to the RedArc, then to the main battery. Take the RedArc earth to the main battery earth. Test by replacing the Aux battery with a bulb across the Redarc output to see when it switches? At 13.2 v the aux battery is unlikely to reach full charge, but should still charge to >60% or so. Maverik - alternators have an inductive source impedance. If you interrupt current in an inductor you get voltage flyback (as in coil ignition). High(er) voltages can blow the diode stack, especially on older alternators - cheap, low voltage rating diodes used. Though I haven't heard of one blowing for some years now.

The RedArc system as described ought to work. If I've guessed at the right system and read the specs correctly, it should isolate when the main battery is 12.7v or less and connect both batteries together once the voltage exceeds 13.2v. So, perhaps an initial delay in charging the auxiliary after starting, until the main battery voltage reaches 13.2 v Need to perform a logical check through the system. Where does the RedArc pick up it's earth? Is there a voltage between RedArc earth and Main earth? and Aux earth? between Aux and main earth?

As implied above, don't rely on voltage to tell you when the battery is fully charged. Leisure batteries have differeent charge/discharge characteristics to standard automotive batteries and it's not just the depth of discharge. Automotive batteries try to maximise plate surface area which helps to give the high current capability - a lot of dependence on surface charge. Leisure batteries have more solid plates and so depend more on deep charge. Try and recharge at too high a rate and you'll never charge to full capacity. The effect is even obvious on standard auto batteries. My battery charger has auto voltage cut-off and two charging current levels (equates to C/8 and C/20). The C/8 rate only takes me to 83% of capacity, C/20 gets me another 15-17%. Richard Perez has written quite a lot on the subject at a laymans level http://www.zetatalk4.com/docs/Batteries/FAQ/State_Of_Charge_Ver_Voltage_2004+.pdf

Have just checked the specs on the ARB 47l. http://www.arb.com.au/products/fridges-camping-accessories/arb-fridge-freezers/ It reckons average power consumption of 0.87A/hr and 12V at 3C cabinet temp, external temp 26-31C tested over a 66 hour period. The manual http://www.carid.com/images/arb/car-organizers/pdf/fridge-freezer-users-guide.pdf suggests a 15A fuse for 7A rated current, so roughly 10% duty cycle. If these figures are correct and the battery is good, it would suggest that you are not charging the auxiliary - 85AH at 0.87A/hr is roughly 100 hours. Unless I have misunderstood your problem you are getting 75 hours. Rather a coincidence. Verify it by running the fridge directly from a fully charged auxiliary and see how long it runs.

Suggest that you check the law before buying. My understanding is that children under 14 are not allowed in sideways facing seats.

I think that Maverik has part of the answer, but not all. If a "proper fridge" ie temperature controlled via built in thermostat then duty cycle will need to be taken into account and useable life may be extended by improving air circulation around the fridge. Even a low power fan could make a lot of difference to energy required. However, a lot of "fridges" are just cool boxes using a Peltier effect element. They take more or less constant current. I'm assuming from the wattage and the need for maintaining a decent beer temperature that it is thermostatically controlled. Suspect that surface charge versus deep charge also comes into this. Energy is stored as a reversible chemical reaction. With a fully charged battery that chemical reaction is at the surface of the battery. Discharge it and the surface reaction has been "used up" and the slower deep reaction takes over. Net effect - higher internal impedance at lower states of charge. I looked up some charge curves on deep cycle (leisure) lead acid batteries. Whilst charging, with 14.5 volts at the battery terminals terminal voltage, the associated battery charge can be somewhere between 85% and 110% of nominal depending on charge rate, with the 85% representing a C/5 rate and 110%, C/40. In your case C is 85A. Discharge your battery too low and it never reaches full capacity under charge. Because of the way that you run it, your main battery could well be running near the surface charge region and therefore hogging charge. Does your alternator regulate at it's terminals or take a sense wire from the main battery?

'98 300Tdi, 110 CSW. From position directly above centre of rear wheel to the rear face of the cross member just measured at 92cm.

Zardos is correct in implying that contact breakers, fuses etc are largely there to protect the wiring and not the winch. If the winch starts taking vastly excessive current it's probably dead anyway and not much further to protect.