November 30, 2020

16. Engine Loom Build

It was that time to make a start of the engine wiring loom. Spent many evenings planning the loom out with a spreadsheet, plan was to have two Deutsch HDP20s as bulkhead connectors, the other side of which will be right next to the PMU/EMU Black.

Here is a list of every connector I had planned for the engine loom:

Coolant Fans
Headlight Left and Right
Windscreen Wiper
Injector 1, 2, 3 and 4
Coils
Starter Motor
Throttle Body
Dephaser Solenoid
Crank Sensor
Coolant Temperature
Intake Air Temperature
MAP Sensor
Engine Oil Temperature
Engine Oil Pressure
Oil Level Sensor
Knock Sensor
Fuel Pressure Sensor
Alternator Signal
Gearbox Oil Temperature
Brake Pressure
Wide Band O2 Sensor
Brake Fluid Level
Wheel Speed Left and Right
Fire Extinguisher Button
Battery Isolator Kill Button

I had previously made a wiring loom, many years ago, for a formula student car so knew that planning was key. Wanted to try and make it as robust as possible so watched the HPA wiring course which gave lots of useful information and design ideas.

First step was to plan the routing and then make a template, used a couple sizes of rope to make it and lots of cable ties.

This template was then transferred onto a board with each branch/junction marked with a cable tie mount.

Then could start running wires marking them off one by one of the spreadsheet and putting a cable marker at the bulkhead end to make it easier for when I come to pin the bulkhead connectors. Once I had placed all the wires I started to remove the cable ties and replace them with kapton tape.

For sleeving I used adhesive lined heat shrink from hilltop products and raychem SCL (rigid heat shrink) for all joints and branches. I added a cable tie at each branch to add some additional support.

Once all the sleeving was complete I fitted the loom into the car which then meant I could complete all the connector ends. Found it just as easy to complete these with the loom in the car as then all the lengths could be bang on. So same as running the wires I worked my way through the spreadsheet marking each connector off as I went. I will do another post with each of the new standard OEM electrical connectors I found.

That just left the 2 bulkhead connectors to do. The Deutsch HDP20 connectors are great, very easy to crimp and pin so would highly recommend and are a fraction of the price of Autosport connectors.

I did have some boots for the bulkhead connectors but I had not left anywhere near enough room between the connector and branch to allow the boot to be slid past the end of the wires to pin the connector first so that one thing I would do different next time but the connectors are meant to be water proof without the boots so should be fine.

Then had the other side of the bulkhead connectors to do which only had a short length of wire to the PMU and EMU Black.