Club 80-90 Forums

It's a pain to get the battery out and recharge. Much easier to fit an isolator switch to the negative, The switch is quite big, just looking for ideas on a good place to fit it

Just as a matter of interest, and for clarity, why do you have to take it out to charge it, and why will fitting an isolator switch to the negative help?

I park on the street so I can't trickle charge. There doesn't seem to be any drain on my battery just my journeys are short at the moment so the battery doesn't get recharged. I like to heat the van up before the kids get in because ny daughter is prone to chest infections but the battert is discharged. My thinking is that fitting an isolater will guarantee that there isnt a drain on the battery when its parked up.

In that case an isolator switch will have no effect, unless you have a drain on that battery from a hi-fi system etc.

Ah, I take it you mean heat the van up with Propex or Eber et al ? and this runs off the leisure battery, which is often flat(ish).

OK, assuming that is correct, a few questions to enable "us" to help you :-

How often has this leisure battery gone really pretty flat?

Is your stereo connected to the main electrics as normal, or have you altered it so it runs off this leisure battery?

Do you have a multimeter with an "Amps"? If yes, can you tell us what the highest "Amp" setting is on the knob? (as in say "500mA" which is 1/2 an Amp, or hopefully higher as in say "10 Amps")

Let us know

flyinghitop wrote:There doesn't seem to be any drain on my battery

If there's no drain, then isolating it won't stop the drain, so won't affect how it discharges.

just my journeys are short at the moment so the battery doesn't get recharged.

Isolating it probably makes it more likely that you'll forget to reconnect it, so it won't even get the little charge it gets now, tbh.

Quickest, cheapest, easiest way of isolating is probably to fit a quick-release battery clamp.
http://www.ebay.co.uk/itm/261319001655" onclick="window.open(this.href);return false;

If you only fit one, fit it to the -ve. That way, if/when you forget to reconnect, you won't suffer the sparky embarrassment of the alternator shorting through the dangling +ve when you drive off and the split-charge kicks in...

One of those small solar panels that go inside the windscreen may help

lloydy wrote:One of those small solar panels that go inside the windscreen may help

In my experience (and CovKkid and I did some testing) anything less than say 30W ones are a waste of space, especially at this time of year.

Of course, as they say, "your mileage may vary" though

Bought one of those quick release clamps, hadn't seen that design, the types I'd seen were too big to fit on an 096 battery and allow the seat base to slide back. It'll give me peace of mind. Have just bought a meter on ebay. The Propex has been bodged onto the water pump switch which drains the battery if I forget to switch it off. I'll get the propex supply(and an RC switch ) sorted amongst other niggling things when I have the readies

ghost123uk wrote:Ah, I take it you mean heat the van up with Propex or Eber et al ? and this runs off the leisure battery, which is often flat(ish).

OK, assuming that is correct, a few questions to enable "us" to help you :-

How often has this leisure battery gone really pretty flat?

Is your stereo connected to the main electrics as normal, or have you altered it so it runs off this leisure battery?

Do you have a multimeter with an "Amps"? If yes, can you tell us what the highest "Amp" setting is on the knob? (as in say "500mA" which is 1/2 an Amp, or hopefully higher as in say "10 Amps")

Let us know

096 Battery four months old says 74A on battery
Never gone totally flat
Yes the stereo runs off the leisure battery
Just got multimeter with 10A setting
Battery showing 12.61 volts engine off.
12.91 with radio headlights and propex on

thanks

OK, so mostly good, but :-

flyinghitop wrote: 12.91 with radio headlights and propex on

If that 12.91 Volts with radio headlights and Propex on is with the engine running then there is something wrong. At 12.91 Volts, your leisure battery is receiving virtually no charge at all. It should be a minimum of 13.6 and preferably up to 14 Volts. The next test is to measure the voltage at the main battery under the same conditions, and compare it to the 12.91 you are getting at the leisure battery. If you get above say 13.4 Volts at the main battery, but only 12.91 Volts at the leisure battery, then the wiring and split charge relay that connect the two when the engine is running is not as efficient as it should be, possibly due to either bad connections, wire too thin, or relay not up to the job.

However, if your Voltage at the main battery is also low, under those same conditions ^^^, then you have either a faulty Voltage regulator/brush pack in your alternator, or you have dodgy wiring from the alternator to the main battery (quite common) or defective earthing from either the main battery to the body, or the engine to the chassis. You can test for dodgy earthing from engine to chassis by firing up the engine, running your lights etc as above and then checking with your meter set to say 20 Volts by putting one probe (doesn't matter which) firmly on a clean bit of the alternator, and the other firmly on a bright screw that holds your tail gate lock to the body (near where your willy is when you are bending over the engine!). If you get more than about .1 (1 tenth) of a Volt reading, then the heavy earth strap (which is actually right at the front end of the gearbox and attaches to the chassis) is not connecting well enough. If that is the case, you have to get underneath, remove it, thoroughly clean up where it goes and re-fit it (or replace it). Or, you can fit an auxiliary earth from any solid bit of the engine to any clean solid bit of the chassis, such as where the engine support cross beam bolts on. Those very heavy earth cables are easily got from most motor factors and not dear. You can do the same test regarding the battery earth. Just put your meter probe on the -ve of the battery and a good clean bit of body nearby (engine running and lights and Propex on). There should be no reading, or at least hardly any at all, like less than .1 of a Volt. If there is a reading, the battery's earth cable needs attention.

Next thing to do is measure what voltage is coming out of the big terminal on the back of your alternator. It needs to be at least 13.8 Volts bare minimum. Do all/any testing under the same load conditions as you have been doing. If it's less than 13.8 Volts, get a new regulator/brush pack fitted, they are only about £15. Brickwerks will sell you a good make, or Ebay if you want to save on postage costs. If it is an OK level, say 13.8 Volts at the alternator, but more than 1/2 a volt less at the main battery, then you will likely have the dodgy wiring condition (from alternator to main battery) I mentioned above. CovKid will be along soon to point you in the direction of the excellent write up and discussion he did a few weeks ago on this. I will be doing as he did, to improve mine, when the weather warms up. In the meantime one could just add another fairly sturdy (64 Amp = 6mm squared) cable from the main alternator output to the main battery +ve (making VERY VERY sure it ain't going to chafe through anywhere along it's length = IMPORTANT that )

Another thing to check is the drain on your leisure under "parked up" conditions. Set your meter to the 10 Amp scale (note, you normally have to put the red lead into the socket on the meter marked either "Amps2 or "10 Amp". Turn everything on the van off, (like the radio, propex etc), remove the -Ve lead from the leisure battery and temporarily connect the 2 leads from your meter, one to the battery terminal and one to the lead you just took off. You cannot get a shock of 12 Volts so you can safely just hold the probes in place with your fingers. Make a note of the current reading on the meter. It should be less than 100mA (which is the same as .1 of an Amp, ie 1/10 of an Amp). Hopefully it will be well less than that. If it is more, report back. The radio's "memory" circuit is usually the culprit for a good few 10's of milliamps drain, usually between 10 and 80 mA.

btw, I reckon it will take less time to actually do those tests that in took to write it

By the way, always always remember, after using your meter on any of the "Amp or mA" settings, ALWAYS, set the dial back to a Volt scale and if you have had the meter on the 10 Amp scale, where you had to move the red probe into the socket marked "Amps" or "10 Amps" , remember to put the probe back into the normal socket. Do this every time, immediately you have finished testing for "Amps". Failing to do so will nearly always result in the destruction of your meter, in a big puff of smoke, the next time you go to measure "Voltage". (when it is set to "Amps", connecting it across a voltage source provides a total short circuit, not dangerous to you, but wrecks your test meter - note = some have a fuse, though many don't !!)

Think you've got it.
Leisure battery lower than main battery so need to look at split charge.(the relay looks pretty knocked about)
0.14 from alternator to earth so looks like I need to change the main earth strap.
Positive terminal on alternator reading 13.75 so brush pack required. Better get looking at Haynes
No drain and main battery earth is fine although it looks grim so I'll change it anyway.

Thank for the clear instructions, the only problem is I was looking too low for the silver screw I was convinced that the battery was draining not that it just wasn't getting enough juice in the first place. You're right about the postage I'm always looking at getting things singly from Brickwerks -I should wait until I've got enough bits needed before ordering. Especially at Christmas time when the postage was crazy

Ghost asked me to post this link on his behalf. We've had numerous conversations about having a good electrical backbone in a camper/van and that without this being right, you can chase your own tail on voltage loss:

https://club8090.co.uk/wiki/VW ... ain_cables" onclick="window.open(this.href);return false;

Its a good reference point to start with as anything after that is much easier to resolve.

the above wiki link is very good,well worth reading