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Electrical upgrades

ByronJ

Well-Known Member
Joined
Jul 7, 2012
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349
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wales
I finished baselining my 1994 80 'Elsie/LC' earlier last year and since then she has been my daily drive. As part of the work I installed a new AC compressor, condenser and filter but even so the aircon never worked for long; clearly the gas was leaking out somewhere.

At last we found the leak this August! It was in a really awkward place near where the high pressure line has a pipe tapped in to take refrigerant to the console cooler box - just behind the exhaust :grimacing:.

After some debate I decided to do without the cooler box, so we cut the pipes to the cooler and remade the connections to the standard evaporator. Since then the aircon has held its gas and worked fine. So a good result but now no cool drinks...

The cool box was a fun item but it had its drawbacks:
  • it only cooled when the engine was running
  • it had no real temperature control - just cold or very cold
  • it had long lengths of aluminium pipe running under the car which 23 years and hard to get at. So reducing the potential reliability of the aircon system as a whole.
So I decided to install a small compressor fridge in its place. This decision set off a surprisingly long chain of events!

First thing was to convert LC to 12v start. I used the simple approach suggested by @Jon Wildsmith. you need to look at page 12 of this thread https://www.landcruiserclub.net/community/threads/my-grey-80.133289/page-12#post-1278138.

This picture shows the relay which needs its plug disconnected. The relay is the silver box with a red label top right of the picture. The plug is disconnected and can be seen to the left. I found it a bit fiddly to get my hand up there and remove the plug, but I managed :)
TimerRelay01 IMG_3115.JPG

This is a close up of the plug with the jumper in place (some copper earth cable).

Timer Relay Plug IMG_3100.jpg


Now that the 24v change over solenoid was disabled it was time to swap the starter to a 12v. I used the 2.5kW STR70230 from Woods Auto. I had a bit of trouble getting the old starter off as I could not get a 17mm socket onto the top retaining nut. This nut is not that easy to get at anyway and has cables and pipes carefully laid to deter access to it. Eventually I tried an 18mm socket and this slipped straight on and the starter was off a few minutes later.

Someone had had a go at this nut in the past and chew the top of the flats, a few minutes with a file sorted that and the new starter was on (using the 17mm socket :thumbup:). A quick turn of the key and LC stared up immediately.

Now I could split off the Drivers Side (DS) battery to use it as an auxiliary and use the Passenger Side (PS) battery for starting only. I chose this Split Charging system to do the job.
IMG_4189B_01.jpg

What attracted me to this system was:
  • good solid solenoid with a metal case, rated at 250A continuous load
  • remote control panel so you could see what was going on, and monitor battery voltage
  • manual 'LINK' button. Pressing the button links the batteries for 30 minutes or until the next press of the same button
  • over voltage warning (red light) should the alternator exceed 14.4v
The package cost me £80 and when you consider it includes a fitting kit that is a real bargain.
IMG_4186A_01.jpg

I disconnected both ends of the heavy cable connecting the DS +ve to the 24v change over solenoid and clipped the ends out of the way.

After some dithering I fitted the solenoid in front of the PS battery.
IMG_4260C_01.jpg

What you see in this picture is a block of 18mm beech ply bolted to the outside of the radiator; using longer bolts of course. Bolted to this block is a 150mm long strip of stainless flat bar, thus the bar is isolated thermally and electrically from the car. The solenoid is bolted to the stainless bar; being metal this bar will now act as a heat sink. All solenoids get warm when their electromagnet is energised and one this size is likely to get hot so a heat sink can only help.

Using the supplied 16mm2 cable I connected the +ve poles of the batteries via the solenoid. Here you can see it running across the top of the radiator inside some new tubular conduit.
ChargeCable_01.jpg

The lower conduit contains the original DS +ve to 24v Changeover solenoid cable and the alternator B+ cable.

Once the control unit was wired in (as per the sparse instructions) I ran some checks with the ignition off:
  • the control unit was able to display the voltage of both batteries
  • the manual link button immediately triggered the solenoid and linked the batteries.
I was reassured to hear the solenoid engage and disengage with a solid 'CLUNK”. Pressing the 'Link' button again did not unlink the batteries immediately, there was a consistent 5 second delay. Interesting I thought...

A final check all round and I fired the car up. No bangs or sparks :icon-biggrin: and all was working well. The batteries linked very quickly and voltage checks at the batteries showed that both were charging.

This is the control unit, complete with spelling mistake!
IMG_4308D_01.jpg


When the untit detects a voltage of 13.3v or more at either battery it connects them. When it detects a voltage of 12.8v or less at either battery it disconnects them. Although it is not mentioned in the specifications the control unit waits 5 seconds between each connect / disconnect decision. This a good thing as when the auxiliary battery is very flat it can immediately pull the starter battery below 12.8v on connection and if the delay was not in place the solenoid could rapidly connect and disconnect the batteries, a problem known as 'chattering'. This unit is much better behaved than that :thumbup:

So now on to fitting the fridge.
 
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Looks like you've been busy Byron :D
 
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The first job was to remove the original cooler box. Once I got the outer casing off I could get at the refrigerant pipes and disconnect them. I was surprised at how many electrical bits were attached to the cooler box. I kept all the bits so if anyone would like some spares just let me know.
IMG_4100_01.jpg

This left me with a couple of holes in the floor.
IMG_4113_01.jpg

So I got hold of an old aluminium pan and cut this out.
IMG_4168_01.jpg

Then glued it over the hole (with a pilot hole already drilled).
IMG_4172_01.jpg

Next I ran a 10mm2 cable, with its entire length enclosed in tubular conduit, from the DS battery under the car (clipped to the body) and up through a grommet in the floor. The other cables shown are for the split charger control panel and are clipped in the same way but run in their own conduit.
IMG_4198_01.jpg

I utilised a Mega Fuse holder (with no fuse inside) Like this:
IMG_4208_01.jpg

to house an external blade fuse holder at the battery end of the cable and inserted a 10A fuse.
IMG_4258_01.jpg

It can be seen above to the right, the red wire entering the top is from the DS battery and the black/red wire entering from the left is from the VSR solenoid. The external fuse is on the right. The cable to the junction under the fridge support exits from the bottom but is not visible in this picture.

Next job was to make a base for the fridge. Here it is bolted in place. The feet of the fridge drop into those holes and a strap holds it down onto the base.
IMG_4176_01.jpg

It seems a simple approach, but that is what Dometic suggest. It feels secure and it has worked very well so far. The drivers seat is slid well forward to show the rear of the fridge support more clearly.
IMG_4326_01.jpg

The other end of the cable terminates at a connector like this
IMG_4209_01.jpg

Which is bolted to the underneath of the fridge base.

power is then taken off through this fuse box
IMG_4324_01.jpg

The fridge is powered through a 5A fuse. The other connections will be for USB charging ports and the music system. This fusebox is only accessible when the PS seat is slid all the way forward.
IMG_4178_01.jpg
The fridge works very well and I am impressed with how well insulated it is. Its rating is A++. My next job was to sort out the excess cable and paint/cover the fridge base but I started getting the familiar 'flashing lights on the dash' problem :cry:.

I cleaned the plug on the back of the alternator but the problem remained. As I had been running the fridge continuously the alternator was having to work harder than before and I wondered if it was not up to the job.

I tested the alternator by monitoring its voltage output with the engine idling at 800 rpm. With minimal load on the battery the voltage was 13.3v but as I switched on headlights, rear demister etc. this dropped to < 12.8v. Time for alternator overhaul:grimacing:. As it looks to be the original alternator I ordered a replacement from http://www.startermotor-alternator.co.uk/.

It arrived the next day
IMG_4252.JPG

Once the new alternator was fitted the voltage remained over 13v at engine 800 rpm no matter what I switched on and the disco light show was no more :icon-biggrin:.

While I was driving around with the old alternator I noticed that when I was idling in traffic the VSR would disconnect if I was putting a heavy load on the electrical system, demist, wipers, fan wipers and so on - a typical summers day in Wales. Once disconnected the auxiliary battery was then supplying current to all these systems with no help from the alternator. After a short while the voltage on the start battery would creep up above 13.3v and the VSR would connect again. But now as the auxiliary was depleted even further it would invariable disconnect 5 seconds later. This switching continued until I was consistently running the engine above 1800 rpm - not often achieved in traffic!

So I resolved to move all the cars standard electrical demands to the starter battery and did this as part of the install of the new alternator. This proved to be a simple task.

I bolted another one of these to the DS battery box:
IMG_4209_01.jpg

To one of the 8mm studs I connected the cars auxiliary cables and one end of the original battery to battery cable, the other end of the cable I connected back to its position on the 24v change over solenoid. To the other stud I connected the B+ of the alternator via a 25mm2 cable.
IMG_4258_01.jpg

I know we have just seen this image a bit earlier but we are now looking at the black box top left of the battery box.

The DS battery only supplies power to the new auxiliary circuit. Every thing else is powered from the PS battery. Now once the batteries are linked they stay linked. The new alternator is clearly generating more power than the old but the system feels cleaner now. I was thinking of making this change anyway as it made it simpler to install an emergency earth disconnect system...
 
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Looking good Byron. Just make sure every cable less than starter cable size is fused. Even the 16mm needs fusing at both batteries as close to the terminals as you can, ideally on the battery terminal post as there are post mounted fuse holders available. This is not so much for overload as for short circuit. If you have a smash you want any short to disconnect. Other than that, it certainly looks like you're doing a fine job protecting those cables. Good work.
 
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I fused all battery/alternator cables using cube style fuses, so protection right where it is most effective.

Regards

Dave
 
The next job was to install emergency cut-out switches to both batteries. I wanted these switches to be accessible from outside the car but not to be obvious or easy for fools to mess with. After some research I came across this switch from Durite 0-605-20. At 24v it is rated 100A continuous, 500A for 5 seconds and has a removable key in the on or off position.
IMG_4207.JPG


I mounted each switch behind the grill.

IMG_4273.JPG


On the left you can see the key entry for the auxiliary battery and on the right the main battery cut-off is covered by a black disk. The discs are actually aluminium dog id tags which are fixed to the grill using these tiny stainless fittings

IMG_4279.JPG


As the nuts have a locking collar it was simple enough to bolt the discs in place so they could be rotated when necessary. Like so:

IMG_4301.JPG


For each battery I mounted heavy duty connector.

FullSizeRender.jpg


Then ran an earth cable from the battery to the switch and from the switch back to the connector. This makes for a simple installation and additional earth connections can easily be added to the connector with compromising the cut-out switch. This also leaves a very clean looking battery :sunglasses:. Below is the auxiliary battery with its 25mm2 cables which are more than ample.

IMG_4255.JPG


The start battery has 35mm2 earth cables and starts the engine with no problem. Fitting the cut-out switches has increased the length of each earth connection by nearly 2m. At 220A (max cranking draw) this introduces a drop of 0.22v across the 35mm2 cable, with 50mm2 cable the drop would be 0.15v so avoiding a 0.07v did not seem worth worrying about.

This what the finished job looks like.

IMG_4310.JPG


Each switch has its own unique key so to ensure I could easily identify them in the dark I drilled a hole through the main battery keys and fitted a tiny stainless bolt to them.

IMG_4314.JPG


Then I put one set of keys in the glove box and the other on my key ring.

IMG_4341 Keys.JPG


Having thought about the earlier comments from @Dave 2000 and @silvercruiser on fusing I decided to take this opportunity to ensure every cable from the positive terminals was fused on both batteries. As a general “catch all” I also installed a cube fuse, rated at 250A, on the passenger side terminal.

IMG_4431.JPG


All other cables, apart from the starter cable, were then separately fused down the line. This does mean that the starter cable is fused but, while not strictly necessary, it does no harm and could do some good by cutting power if the starter and or cable is compromised in a smash.
 
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Nice to see you used the cube fuses, as mentioned in another thread earlier this week, I used them to protect the cables in the event of a front end shunt, neat and tidy, good post with the pics :dance:

Regards

Dave
 
Nice to see you used the cube fuses, as mentioned in another thread earlier this week, I used them to protect the cables in the event of a front end shunt, neat and tidy, good post with the pics :dance:

Regards

Dave
Thanks Dave. I got the idea of the cube fuse from a post of yours last year :).
 
Nice work Byron as always with your trucks and a very sensible approach.

Have you tackled the bonnet release issue yet?
 
Nice work Byron as always with your trucks and a very sensible approach.

Have you tackled the bonnet release issue yet?

Thanks Mark. I am still fiddling around with secondary bonnet release mechanism. It is easy enough to set one up but keeping it neat, tucked out of sight yet easily accessable, has defeated me so far. Also I have been seriously distracted by my SA Cruiser but plan to have another go at the bonnet release idea soon.

Currently I am designing and building composting toilets as Cape Town is suffering a serious drought. So little water is being flushed down the sewerage systems that they are blocking up :mask:. So our idea is to avoid using the sewers completely. We shall see how we fare...
 
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Sounds interesting and potentially smelly at the same time :) Been following the drought with some professional interest from my environmental work. Unfortunately I think Cape Town will be the first of this type of issue and we'll see more in years to come
 
Sounds interesting and potentially smelly at the same time :) Been following the drought with some professional interest from my environmental work. Unfortunately I think Cape Town will be the first of this type of issue and we'll see more in years to come

Yep. Apparently abut 30% of the clean drinking water produced in the UK is used to flush toilets! Seems such a waste. Though we have no shortage of water of course - certainly not here in Wales. However to use clean drinking water for flushing toilets in Africa seems like madness. I hope some smart ideas and new approaches come out of this drought.
 
Currently I am designing and building composting toilets as Cape Town is suffering a serious drought. So little water is being flushed down the sewerage systems that they are blocking up :mask:. So our idea is to avoid using the sewers completely. We shall see how we fare...

Spanish sorted this year's ago.

Run a pipe from toilet to deep hole that has had a concrete tube inserted, pour gravel around the outside, throw in a dead animal (normally road kill cat or dog) to start bacteria, fit lid job done. :icon-biggrin:

Regards

Dave
 
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