Day 11: more plumbing, and the airbox

I'm waiting for a Caterham engineer to come and look at my chassis, to fit the header tank bracket rivnuts. I was willing to do it myself, but Derek wanted to send someone over insteadair

ull points to Derek, but if I was running Caterham, I'd improve QA to avoid this kind of expense.

In the meantime, my fuel pipe arrived, so I fitted the pipe between the throttle and the fuel purge valve, and tied it to the gearbox breather, and a couple of other useful fittings along the way.

Fitting the heater was done a while ago (while waiting for something else to arrive!), but now my son and I fitted pipes and the heating valve to the copper tails.

Lube the tails before fitting, and consider cutting a bit shorter for a neater fit

We cut them 10mm shorter than specified in the Assembly Guide, as this allows the valve to sit nicer between the battery and heater unit. The heater cable itself is an easy one to fit, and didn't need any adjustment. If you've fitted bicycle brakes, then you'll know how it's done here.

The airbox is about as far as I can go without the header tank, so I fitted the base of that. Again, easy.

A nice easy job, and a big engine bay space now filled

The air filter is from a Ford Fiesta (1729854)

K&N claim that replacing an air filter with their brand can add "between 1 and 4 horsepower". When you've only got 80hp, that's a 1.25-5% increase... at £50 that could be £10/hp, which seems cheap!

The whole question of upgrades and especially performance upgrades is something for another post.

The air mass sensor is from a Renault Clio (8200373771). 


The large hole had already been cut in the air box lid, but needed a bit of shaping to seat the air mass sensor in properly.

I didn't have the right bolts to fit the air sensor, or the lid of the box, but I've bought a couple of boxes of nuts, washers and nyloc bolts and am substituting as I go.

Day 2: waxoyl, front suspension start, and heater

A bit of a frustrating start, as I don't have the IVA parts that are needed to:
- put around the indicators
- cover the ends of the steering racks
So I couldn't complete the front suspension as planned. But some progress made.

I Waxoyled the chassis, focusing on the areas where the frame meets the aluminium panels. The Waxoyl plastic hand pump turned out to be a waste of time, not maintaining enough pressure for more than a few seconds of fairly violent and messy squirting, but that may have been user error...

In the end, I warmed the cannister up in a bucket of hot tap water, stirring regularly and eventually achieving the consistency and appearance of melted garlic butter. Then, it's very easy to paint the frame/skin joins with a 1" paintbrush. The white spirit solvent runs into the gaps, and then evaporates, leaving buttery wax behind. Before the engine goes in, I will go round again, from underneath, and make sure nothing was missed. And also the gaps between the skins around the cockpit, which I will resurrect the hand pump squirter for one last go!

The steering rack is easy to sort out.

Cross-member for mounting the steering rack

And the lower wishbones went in. A couple of tips:

1. make sure the chamfered washers are 'back-to back', i.e. the chamfered edges are on the outside of each pair

2. it is a real squeeze to get the washers in, but they will go in. Essentially, you're fighting against the bush, which is pushing outwards. I managed it by pushing the bolt through the first (rear washer), and then gently tapping the front washer into the gap using a screwdriver blade and rubber mallet (sounds like high-risk tactics, but I mean really small taps). The Coppa Ease that covers everything will help them slide in place

3. once you think the washers are seated properly, then you can gently drive the bolt through them, and beyond through the chassis

4. by contrast, the front arm is much easier to get the washers in. If possible, clear the threads out in the chassis before you start - mine had a bit of paint/swarf which needed clearing.

RH lower wishbone, rear bolt, not tightened up

RH lower wishbone, front bolt

And another coat of varnish on the boot plywood floor, both sides.

Then, I fitted the heater, which is easy. I did run a thin line of clear sealant around the plastic lip at the top of the heater, and about half way down the sides - it looks as if rain could possibly get in along the top, and then run down into the heater casing. This squeezed nicely into place when the bolts were done up.

LHS, heater & fittings

Inside, LHS, heater vents. The two electrical plugs fit together easily

On the inside, the heater vents can be spun around the face the right way (I went for a jaunty angle - see above).

Hopefully, Derek will get me the missing IVA bits tomorrow and I can finish each front corner suspension.l