Rewiring Junior

Waterproofing junior was going well but as I was going to fit a winch soon I decided to move the batteries to the box under the seat. This was also a good opportunity to sort out the wiring under the bonnet and make some room for a bigger alternator and the new air filter system.

The rear lights were connected to the loom under the bonnet and the wiring ran through the chassis. During the reconstruction Ian went to great lengths to prevent damage to this vital wiring but eventually the inevitable happened and we had to design a replacement.  

Running the wire through the chassis seamed like a bad idea as it gets damp and damaged during maintenance.

We decided a separate system to each light cluster would be more robust. If one wire was damaged at least you still have lights to the other side.

This is the waterproof junction box we used to connect everything up. From here separate wires were run to the rear along the top of the chassis. It then goes up through the floor of the rear tub and up to the tub capping. 

The cable clips secure the wires to the bulkhead. The idea was to get the wires up into the tub and away from the mud and water. 

The boxes that cover the rear light wiring are not perfectly waterproof but will keep most of the muck out. the new loom is secured in into the top and of the cover and all the connections inside are waterproofed.

Time will tell is this is sufficient to keep it all working.


In order to make some space under the bonnet and put in a second battery I decided to mover the batteries to the box under the seats. This is designed for tools and isn't as deep as the ones on the defender. I found some high output batteries that would fit in snugly. The holes are to allow the cables in and out and ventilate the area. batteries do produce hydrogen in small quantities so you can't be too careful.  

After fitting the batteries. 

The wiring is all 40mm2 and the starter motor solenoid is an up rated version that includes a started button which is entirely manual. OK its for emergencies but may be useful when all has gone electronically wrong.

I have still to wire in the winches through the other hole.

When I removed the existing alternator I found It was a Vauxhall item on a home made bracket. I know that the standard alternator is a Lucas design but didn't know how they were adapted to fit on to the 2.25 engine block.

Yet again Geoff had the answer. This is the Lucas alternator bracket I needed, fitted, with plenty of copper grease.


  Having fitted the correct mounting bracket the new alternator was fitted. Its allot bigger than he one that was on so I needed a new fan belt. the chaps at Fylde Auto Parts let me take a few to see what fitted. The supply lead is 40mm2 so should be able to take the extra amps to charge up the batteries quickly.
The engine bay is getting a little more organized now.

Here you can see the new washer bottle, Waterproof coil container and the compressor for the distributor cap.

The air supply for this compressor comes from inside the cab so no water can be drawn in

Next Job, Wiring in the electric fan.


On the dash board I needed to have control switches for amongst other things the electric fan and the compressor for the distributor cap. 

I installed a live feed from under the bonnet to the dash board and a good earth point from the bulkhead. these were wired into a junction box to supply a number of applications.

The switches were wired to control the fan and the compressor indirectly using a series of relays.

Click the picture for a wiring diagram of the switched setup. 

Having had the opportunity to sort all the auxiliary wiring to the dash board at the same time, I fitted the control wires for the winch. This was total out of character for me to be so forward thinking,

I made a box to fit to the dash containing the remote control plug from the original control box, and put a selectable push button control panel on the front of the box to enable me to control the winch which driving .