Outer Limits 4x4 Board

Though I haven't installed this system yet, in the instructions it says that sometimes peoples charging system is too small. By that I guess they mean the alternator doesn't put out enough? If my alternator was the standard one in an 88 hilux diesel ( 2.4 ) I guess it is only like 50 amps or so? Is that big enough to run a big aux battery? When I go away I will be running 1-2 lights and a medium size engel. Pretty much it.

The only accessories I have on my car is a small 2 speaker stereo, 2x100w spotties and a uhf ( all hardly get used ). I have 2x50w lights on the rear but I use them for very short bursts ( to see in the dark when unpacking ).

So what yas reckon? Is a standard alternator fine to slowly charge my main battery as well as a decent sized aux bat ?

Cheers guys. I really want the heads up on this.

Given how old this is I imagine you've figured the go through trial and error but since no one else did...

I have had a dual battery in my truck for a couple of years with the std alternator. It's an old GQ which has a pissy 50A alternator. It has worked fine for me the whole time. It does depend on how much time you spend moving and how much time stationary, and the heat. I have had the Aux power the fridge for a full 5 days in cold conditions, and about 30hrs in hot ones. I find that the battery only charges properly when I'm driving, ie not at idle. A couple hours drive tends to get it topped up, so if you don't do much driving with your camping you may need a bigger alt or solar.

I have now just added a third battery to the back for extended stays to get some more life out of it. I picked up a neat little unit from jaycar which is a voltmeter and inside/outside themometer in one. I have rigged it up to the back battery and mounted it on the back of the storage system I built facing forward. Now can monitor the voltage and fridge temp from the drivers seat or from outside the car. Third battery has been in only a few days but is definitely charging OK off the std alt. Was sitting at about 12.3V which is low, about 15mins driving got it up to 12.7 where it belongs. Can also see that while I'm driving it's sitting at 13.4-13.7 indicating charging is going on. Should mention I ran 4 gauge cable to the back battery. Used to be 8 gauge when it just powered the fridge and a Fluro.

More than you wanted to know I'm sure!

Turbz wrote:The only accessories I have on my car is a small 2 speaker stereo, 2x100w spotties and a uhf ( all hardly get used ). I have 2x50w lights on the rear but I use them for very short bursts ( to see in the dark when unpacking ).

If this is all you have then why on earth are you even bothering with a 2nd battery?

Unless you have a fridge then I wouldn't bother.

I also run a 32litre engel. But to update things, I emailed Matson about it and they swiftly replied with a nice understanding email.

They said " Your alternator will have no problem keeping up with your 2 batteries, it should put out around 14V- 14.4V. It’s also a good idea to give the auxiliary battery a charge on a good quality switchmode charger every now and then to keep it in good condition and prolong battery life ".

Good to know. ! CHEERS MATSON!