bowtie6 Wiring – Part II –

Engine wiring is progressing right along,  albeit slow.  This part of building a car takes time!

So far the engine harness is complete.  All wires to the ECM have been accounted for and the main looms have been covered with crinkle tubing.  This tubing protects all wires and keeps things looking neat and professional.

Another engine bay picture showing the fuse box on the left, the coolant overflow tank, coolant lines and brake master cylinder and hydraulic clutch reservoir.  The coolant expansion tank is all hand made aluminium.  Missing from the coolant expansion tank is a small rubber hose going to an overflow tank behind the radiator; also hand made aluminium.  And yes, all the rubber coolant hoses are missing their clamps.  Just haven’t had a chance to get there yet!

Below, is a close up of the new fusebox.  On the bottom left, you see the new fuse box.  This is where all the relays, circuit breakers and fuses that control the engine compartment reside.  This is what it looks like:

So what do we have here?

Starting from the bottom:  below the box, hidden from view is a post that goes through the firewall.  This post is insulated with a Bakelite insulator.  From this post, wires feed battery power to the circuit breakers.  There are a total of seven circuit breakers; one for each relay.

Above the circuit breakers there are seven relays.  They are used as follows:

  1. Horn relay
  2. Electric Fan relay
  3. Headlight “on” relay
  4. Headlight high/low relay
  5. Starter relay
  6. Ignition relay
  7. Start button relay

Finally above all this are two banks of fuses.  To the left of the fuses is the electric fan controller and below that, the engine’s ECM.

Why so many relays?  The idea here is to use a relay for each device that requires high current, for example the electric engine fan.  The idea is to let the switches run low current controlling the electromagnet in each relay.

I know what you are going to say:  where are the turn signals and parking lights?  Yes, they have been left out.  Not by mistake, but by design.  Underneath the dash will be a smaller fuse box, containing fuses and four relays.  This is the part I’m working on now, and will be featured in the next installment…  Stay tuned.

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