Details, Details

October 16th 2013

Now that I've tried the new engine and installation at two events I have just about settled on the spec.
Coming away from the last event at Sedbergh I had a couple of things that really needed attention.

Manifold air leak and rear fiddle brakes.

Air Leaks. I already knew the flange on the manifold was not totally flat. The welding I have done created a bit of bowing. The centre of the flange was the highest part so I had hoped that, using a thickish gasket paper, it would seal properly. However it meant that the lugs on the carb couldn't be tightened right down. there was also a risk that they may crack.
I had already asked my engineer friend if he could plane it on his milling machine, but as the two flanges were offset in two dimensions he couldn't mount it securely on his machine.

This was the original adaptor

Then I added a water jacket to help avoid carb-icing problems. This extra welding probably caused the bowing of the flange.
So I made a jig to hold the flange level.

 I took this for machining and asked him to put a groove in so that I could seal it using a rubber O-ring.

This highlighted the unevenness of the hole I had cut!  I'm not bothered and am not going to smooth off the welds on the inside of the adaptor throat either. This roughness should help tumble the fuel mixture at low revs.
I've now fitted the adaptor and carb. The seal seems to have worked properly and the engine runs well.
I've also connected the water jacket using loads of bits of rubber hose I got from the scrap-yard. This seems to have worked and there are no water leaks.


Fiddle Brakes. I've always felt there wasn't enough travel on the fidddle levers and Brian, who I bought the car from, had had the same feeling.
The master cylinders were 0.70" bore and I found that 0.625" ones were available.

 That amounts to about 10% smaller. Not a lot, but the extra movement on the lever should allow more sensitive control and using the same "pull" would achieve greater clamping pressure.

Taking the pads out showed that the nearside pads (the inner one particularly) had not bedded in as well as the offside ones.

 Nearside

Offside

A competitor suggested this may be due to the custom-built nature of the hubs, discs and calliper mounts. They may not be entirely parallel and high spots on the pads may need wearing down.

I fitted the new master cylinders and after bleeding I jacked the car up and ran in-gear against the brakes for 5 minutes or so. I've yet to pull the pads (which I have marked with dobs of paint, so I can put them back in the correct place) to see if the wear has improved the pad surface.

I've also fed the oil vapour pipe from the rocker cover to the air filter. I'd had it exiting beneath the car but it covered the sump skid with oil mist. That prevents me spotting real oil leaks.

The next things to address are very minor. I want to repaint the rear wheels and close off the hole in the bonnet.

But now I've got the bits of the car working pretty well I need to address getting the thing up some hills. If I don't have to overcome brakes and throttle issues it gives me more scope to concentrate on the surfaces and the grip. Oh and steering in the right direction.