Fitting a Dual Battery

extra $400 installation fee, you're joking, right? If you're not, I would look elsewhere, way too bloody much for installation, or does it include battery and tray and solenoid etc?

Gday Steve,
You will find the dual battery installation from TJM (I assume you are reffering to the VSX, or megeatraonics basic ones), quite easy. I did the installation of a dual battery system on my old 80 series as my first attempt at auto electrics.
The instructions are pretty straight forward...
Probably best to put aside about 3-4 hours if its your first go at this sort of thing, as there is some time needed to head scratch...
The problems I encountered were mainly in the fiiting of the battery tray... after that it was all pretty straight forward, as the isloator unit itself is supplied with fairly long leads and can be fitted anywhere that it will fit.
Be sure to run the wires through as a test fit and make sure they reach the original battery (if fitted on the opposite side of the engine bay).
It may take longer than it would take them to do it, but its more fun if you do it yourself!
Cheers
80

Steve,
The fitting of the battery tray while having to move the carbon cannister will fit OK.Wireing the isolater is also straight forward, the only thing that I did and not sure if they say any thing about it in the instructions is the red wire to activate the black box. Solider that wire to the active wire that runs to the wiper motor. A test light will help you find that wire. Turn the ignition on and test the wires to see which one is active( I think it is blue) . that way you do not tap into the computer system.

Wayne

Steve,

Don't take this the wrong way, but IMHO if the Engel is the only reason you are adding the dual battery system you need to consider if you really need it or not. The Engel's these days will comfortably run by one battery in a vehicle which is used every day or so when tripping. A $20 in-line low voltage cutout (in the fridge circuit) is good for insurance. You can even update/upgrade the main battery and/or buy a decent portable power pack and still have change left.

Regds

Bill

My Waeco runs for 3 days before it trips the low voltage cutout. This is built into the fridge to save the battery for starting. If the Engel has not got one of these then I suggest you get a fridge that does.

Scrap the second battery idea. It is a waste of money unless you need it for long winching sessions, to run a lot of accessories simultaneously or starting diesels in the snow when they have been unused for 2 or more weeks.

Steve,

I've got a lot of mates with V6 Prados. Half of them fit a second battery at great effort and expense and half of them don't and manage fine.

A 40 litre F-series Engel has a very low power consumption so you can easily get by with a single battery. The V6 motor starts with minimal battery power.

So fit the largest N70 size battery into the V6 Prado's standard bay - many I know use the Overlander 700cca cranking batteries. The battery will overhang a little - this is no problem - its the same as whats used with the diesel Prados.

Like Billy says, get a low voltage cutout going to the Engel and you'll always be able to start your vehicle.

I don't suggest that any novices fit a second battery to a V6 Prado. It involves extending the battery leads, as well as moving the charcoal canister, finding a spot for the isolator, and being very good with a soldering iron for a problem- free job.

Cheers
Phil

It really is a very simple procedure.

I have an auxilliary 700cca cranking battery and a Rotronics MH10 battery isolator. The battery cost $130, the isolator $250 and some ancilliary cables about $20. If all else fails read the instructions. Recently I have transferred the whole set up to my newer vehicle. My 2nd battery runs a host of stuff including the Engel. I have had no issues with the set-up.

If TJM is supplying the battery and isolator fitted for $400 then it is a good deal.

Don't mean to hi-jack the topic about the value of a dual battery but I will tell you they are worth every cent.
After travelling in hot climates, I have killed the 2nd battery, had I been running off a single battery I would have been "gone"..... no electrics, no radios etc etc.
This was running a 3 year old engel, it wasn't the fact that it was drawing high current, it was because it was so hot the fridge was running at a very high duty cycle.
Get it atleast for piece of mind.....
Tim
01TD Prado

Thankyou all for the help you have given me, all has been taken into account..I must agree with the two last posts with the heat issue

I am leaning towards installing second battery inside the vehicle as the minimal space underbonnet looks like a headache........ This way I can add a larger sealed battery.............

Steve

The Internet is quite a place for generating and reinforcing info that is simply not true. So may I just kill one such right now before it gets added to the great campfire mythology bank.

That is a comment on this thread that a car starter motor draws a heap energy more than an Engels fridge.

Well it all depends on how long you run that Engels, but a starter motor in fact draws a great deal less energy than most people suspect (assuming the engine is in good order). You can win bets in the pub with this one!

Here's the facts.

A typical starter motor draws 350-400 amps (that's about 100 times the draw of an Engel). But it typically does so for only two to three seconds

In three seconds the starter motor draws 400 amps divided by 3600 seconds times three seconds (in amp/hours). That's way under 1 amp/hour - it's TINY!!!

An Engel fridge typically draws 3.0 -3.5 amps/hour (taking a 50% duty cycle into account that's still 1.5 amps/hour). More than the starter motor - eh?

When the engine starts, that energy is typically replaced within a minute.

The starter battery is typically 70% charged - and starting the battery typically drops that to a mere 68-69%.

Another way of looking at the energy required is to remember that a vintage car can be hand cranked by one hand and with ease, by even a slightly built person. I spent my formative years driving them and my girl friends then could readily hand crank my 1927 4.5 litre (4cyl) Bentley (mind you I did like strong girls!)

I should add that whilst you may get away with running the fridge from the starter battery you really are pushing your luck! If it really had that energy to spare the bloody car industry bean counters would have cut it back in size decades ago!
Trust this is of interest.
Collyn Rivers