Radiator Pipes

Out with the cardboard and scissors to plan the route for the radiator top and bottom hoses.

Top hose = easy. 45deg bend out the thermostat (with 8mm take off for header tank)into a 450mm long straight bit of ali pipe, then some flexible hose into the top of the radiator which is at a jaunty 20deg angle.

Bottom hose = difficult. Loads of posts on the cobra forum about this, hoses going under the steering rack, very close to the floor, or alternatively hoses going through the middle of the camber compensating rods. After an hour of blue petering we arrived at a compromise solution, made even more difficult by the fact that the lower engine water outlet is 45mm, the radiator is 35mm and the fan switch I bought is 38mm.

Eventually, we came up with the following route: 90deg 35-38mm elbow out the radiator straight into the fan switch. That goes into a 90deg 38-46mm elbow which takes you onto the fore/aft alignment, roughly in the centre. 150mm ali hose joiner into a jauntily angled 45 deg elbow that takes you  OVER the top of the steering column. Another short straight hose join (with a 3/8 tapped hole for the 16mm ID header tank take off) to a 45deg elbow, another very short hose joiner (76mm from Merlin is their shortest standard length) into another 45 deg elbow to get you onto the lower water inlet of the engine.

Throttle Cable

The throttle cable is now fitted to the carb. Haven't done the pedal end yet but its fun to stand and pull the cable by hand and open/close the throttle. I bought the standard cable from Dax which came with a single spring and a bracket which goes on one of the rear carb fixings. There was a tiny hole drilled in the bracket to take one end of the spring but it was too close to the body of the carb and the spring fouled on some of the external throttle mechanism so I drilled a new 2.5mm hole a bit further out so the spring didn't catch.

Video of clutch working:

There isn't quite enough travel on the release arm. The clutch disengages on about 90% pedal travel and when the prop shaft is turned by hand you can feel it dragging slightly with the pedal all the way to the floor. Sadly this is because my clutch master and slave cylinders are mis-matched. I've got 7/8 slave and 3/4 master so I've got less movement at the slave (onto the clutch arm) per pedal distance moved. Most people have it the other way round (d'oh!). Due to our clutch release arm being chopped by 1.5 the stroke required is slightly less (but more effort) so I reckon that 7/8 master and 7/8 slave should be sufficient, with the clutch biting about halfway down the pedal. Not ideal but I'll give it a go. The one good thing about getting this wrong is that we now understand fully how it all works, rather than just bolting the parts together and moving on to the next job. It does mean that the excellent job we did of filling the system with fluid and bleeding it now has to be repeated.

before and after

Just realised how far we've come

Final Engine Connections

Getting closer to engine first start. This afternoon I fitted the heater hoses to the manifold and water pump as I got some 1/2NPT to 16mm hose barb(whatever that is in old-man fractions) from Summit racing in the states. Its absolutely impossible to get them in the UK unless you want brass plumbing fittings, which look rubbish.

Having said that I got an absolutely horrendous looking blue anodised 3/8NPT to 1/2 hose  barb for the vacuum hose from the brake servo. Couldnt get it in chrome, or any other material for that matter. It makes me sick to look at it, piece of jap tuner crap but its all I could find that fits. The hose I've got is actually 7/16 but with much huffing and puffing I got it on the 1/2 hose barb. Luckily the air filter will cover it up when its fitted. The servo bends in a nice S shape to the brake servo so any condensed fuel will run back downhill into the manifold rather than to the brake servo.

Ah yes, I had to remove the carb to fit the hose barb thing. That was a bad idea. I almost pooped myself when I knocked a tray of screws flying and I thought one had gone into the manifold. After a full hour of searching I had accounted for all screws and washers so thankfully didn't have to remove the inlet manifold.