Technically this post is about the preparation of the de Dion tube, and the location of it in the chassis. It’s only really installed when the radius arms, shock absorbers and A-frame are installed.

I started by locating rear brake lines, which were in different boxes, because of the length of the left-hand-side.

The manual (v1.2 and v2.0) calls for the holes on the top of the de Dion tube to be enlarged to 1/8″. Unfortunately, I don’t own a 1/8″ drill, so I tried a 3mm first. This did not provide enough clearance for the pop rivet, so I enlarged them again 3.5mm. I know this a little over the specified 1/8″, but the pop rivet should be able to fill the gap.

I then protected the bare metal with POR15 and left the paint on the de Dion tube to dry, before attaching the brake lines.

Note the P clip direction

There are a few things to note. The P-clips for the left-hand-side and right-hand-side point in opposite directions, and the fittings are imperial (not metric), but I am getting used to that by now.

I made a mistake here, and decided to install the rear brake hose when the de Dion tube was in the chassis. Although the task isn’t impossible, it would have been easier to install the rear brake hose on the bench, before placing it in the chassis.

Cutting the protection fuel hose without slicing chunks out of myself led me to squeeze the fuel hose in my Workmate and slice the fuel hose as straight as possible.

Once cut, the fuel hose simply slipped over the rear brake hose, and a few tie wraps completed the process. This fuel hose protection of the brake hose is an IVA requirement.

Before placing the de Dion tube into the chassis, I decided to put a little protection in place: a layer of cardboard on the fuel tank, some pipe lagging on the chassis tubes and a rag on the de Dion tube end I was going to feed through the chassis.

Placing the de Dion tube into the chassis involves careful manoeuvring: The A-frame mount initially points towards the front of the car, and the tube should be angled towards the ground, until the end (ear mount) clears the differential. At this point, the tube can be pushed in and rotated into the correct position, A-frame mount pointing towards the ground. I am sorry I didn’t get any pictures, my hands were rather full at that point of time.

With the tube in place, I attached the rear brake hose. First I tightened hose into the T-junction first, then I tightened the lock nut. The best fit I found for this lock nut was 14mm metric.

Tools Used

  • Drill
  • Knife
  • Manual pop riveter
  • 7/16″ 3/8″ drive socket
  • 3/8″ drive ratchet
  • 7/16″ ratchet ring spanner
  • 14mm combination spanner
  • 1/2″ flare spanner