Day 25: oils and brake bleeding

I intended to start the engine for the first time today. But... shortages got in the way. The bottom LH corner of the radiator is missing a drain plug. I hadn't even noticed it when I put it on the car, it's not mentioned in the Assembly Guide, and Derek at Caterham was surprised it wasn't there, as they usually just arrive in place.

Oh well. So, nevertheless, I filled the gear oil with about 1.3l, and the differential with about 1.5l. The gear oil is easily reached, although the drain hole is very hard to access.

Like many other builders, I made my own tool from a piece of 3/8" steel, gripped by an old 3/8" spanner.

Dremelling off a section of 3/8" square bar from an unwanted socket set 3/8"-1/2" convertor

Gearbox overflow tool. Narrow enough to get between the tunnel wall and the gearbox

The diff oil is best attacked from above, removing the wooden and honeycomb floors. However, now that the rollover bar is in place, I can't remove the honeycomb floor section, so just propped it up (covered in masking tape, as it is very sharp and easily could damage the paintwork).

Filling the diff oil

Brakes
Then onto bleeding the brakes. I went for the traditional 2-person method, rather than use my Eazibleed. No real reason, other than I wanted to work on it with one of my kids, who sat in the cockpit for ages pumping the brake pedal.

Couple of things worth mentioning:
- it takes a long time
- there are two bleed nipples on each front upright. I only remembered this when I removed the front wheels to see why things were not improving. I bled both
- as the bleeding process goes on, the handbrake starts to be able to move, having been jammed on in the lowest position earlier

I think the brakes are due another round of bleeding before I'm happy with them.

So now, I'm just waiting for:
- stainless rear wing protectors (wrong size delivered)
- radiator drain plug

Day 21: rear brakes, handbrake, speed sensors

The kit arrived a month ago. I thought it would take me two months to build, but I'm very much at the end of the build now. Despite days wasted due to shortages, things have progressed nicely.

Today was finishing connecting up the rear brakes, handbrake cables and starting on the interior.

The rear brakes are supplied with hydraulic fluid via a brake pipe through the tunnel. Then pressure is delivered via a flexible pipe into the RH rear brake, and connected to the LH brake via another rigid brake pipe, mounted on the live axle.

The rigid brake pipe will need a bit of manipulating. But working along, clipping it into place, it just needed finger-bending and settled into place easily.

LH rear brake. Brake pipe visible going off to the RH rear brake. Speed sensor visible on left of photo

Rigid brake pipe fixed to live axle using small plastic clips

The speed sensors are easily fitted, and a few more cable ties keep them neat (I must have used nearly 100 over the car by now...). 

RH rear wheel from behind. From the bottom, you can see the flexible brake pipe, the rigid brake pipe and the speed sensor 

The two handbrake cables are connected easily into the brake drums, and are then taken into the tunnel, crossing over on the way. It all feels very logical and clear. 

Axle from RHS, with handbrake cable visible lying just clear above the axle

Back of the tunnel, from above. The handbrake cables connect to the T-fitting on the back of the handbrake bracket

 Lastly, most of the above pic was covered up by the tunnel plate, rivetted on. 

Day 15: Handbrake and differential

Having pretty much completed the front of the car (save for the cycle wings and indicator repeaters), it's time to attack the back.

First job was to fit the handbrake. On the face of it, this is easy. But a couple of tips:
- the handbrake is much narrower than the gap between the two brackets. You need to nip up the nuts and bolts so that the gap is drawn together and the handbrake doesn't wobble
- the electrical connections both turn on and off with the switch. Tested with a multimeter
- I put some heatshrink around the lower connector, as it was very close to the chassis (and would have shorted)

Looking at the RHS of the main handbrake, you can see 1) the white connector for the handbrake warning light, below that 2) a bit of heatshrink around the other terminal then below that 3) the red earth connector

Handbrake assembly from above

Second job was to fit the differential into the rear axle casing. This is taken from the Suzuki Jimny, but the rear axle is then comprehensively tweaked, re-welded, etc etc. In doing so, various slots and rebates are cut, to allow the diff in.

Now, that's the theory. In practice, my diff didn't fit at all. There is only one way in: with the ring gear (the biggest gear wheel) dropping into the deeper part of the axle casing. But the rebates had not been cut too well, and it jammed.

So, after a big head-scratch, out came the Dremel, and two small areas were ground back by less than 1mm.

The rebate on the LHS shows where my attempts to fit the diff started to scrape the casing...

So I took the corner off with the Dremel...

On both sides..

Hey presto, the diff dropped in perfectly, and was easily torqued up. The breather feels insubstantial, but is easily fitted.

All fitted together, with gasket leaching out between the two (probably put a bit too much on)