Orphir walk

Mentioned in the 1136 Orkneyinga saga the Orphir circular Kirk is the last remaining circular church in Scotland. The plan is said to be inspired by the rotunda of the Holy Sepulcher in Jerusalem which was increasingly visited by pilgrims following the capture of the Holy Land in the first Crusade. One of these was Earl Hakon who traveled there to atone for ordering the death of St. Magnus on Egilsay in about 1116. The Orphir Kirk may have been built after his return and before his death in about 1123.

Orphir round kirk Orphir round kirk

The St Magnus trail follows the coast round the north shore of Scapa Flow.

Shoreline near Orphir

The wall round the edge of the field has a heavy covering of lichen.

Lichen on a stone

Further along the headland are a pair of fishermans’ cottages.

Fishermen's huts

The tip of the headland looks out onto the stretch of water where on 5th August 1917 Squadron Commander Edwin Dunning became the first person to land a plane on a moving ship.  Taking off from Smoogro in a Sopwith Pup he landed on the flying off deck of HMS Furious dodging the funnels and the turbulence they produced.  Well before the invention of arrester wires a grappling party of the ship’s deck hands grabbed hold of ropes that had been attached to the plane in order to restrain it.  Unfortunately five days later he died attempting to repeat the feat when, despite the best efforts of the grappling party, his aircraft fell off the side of the deck and he drowned.

Shoreline near Orphir

Continuing along the path the coast line flattens out and there is now a fish farm close to the shore.

Shoreline near Orphir Shoreline near Orphir and fish farm offshore

Returning to the fishermens’ cottages and heading inland near Gyre farm there is a small area of woodland, very unusual for Orkney.

Gyre farm woods Gyre farm woods

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Standing stones walk

The first set of standing stones were the Stones of Stenness.  The name comes from the Norse Stein Ness meaning stone point which suggests they have been the dominant feature of this area for most of human history as this is one of the oldest henges in the British Isles.

Stones of Stenness

Behind the stones is a settlement.  This features a large building surrounded by circular borders and the entrance to the Standing Stones faced in this direction suggesting it had some form of ceremonial significance.

Barnhouse settlement

Next to this is a building with two hearths that is constructed in a similar way to burial cairns which suggests this was also a significant, non-residential, building.  Behind this is a residential building, similar to those found at Skara Brae.

Barnhouse settlement

Following the path towards the Ring of Brodgar past the Loch of Stenness the peaks of Hoy are visible in the distance.

Loch of Stenness and Hoy

The Ring of Brodgar is a much larger stone circle that is 500-1000 years newer than the Stones of Stenness and is the third largest in the British Isles.

Ring of Brodgar Ring of Brodgar

The path returns to the Stones of Stenness and on the other side of the cuaseway that links them lies Loch Harray.

Ring of Brodgar Loch of Harray Standing Stones of Stenness

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Replacing the primary jet in a 2CV carburettor

The later models of 2CVs come with a twin choke carburettor with the primary (smaller) being used at low revs and a mechanical linkage opening the secondary (larger) as the throttle is depressed further.  Fuel is allowed into the venturi from the bowls by small brass jets (screws with calibrated holes in the middle), the size of which controls the fuel/air mixture.  As standard the primary jet is a 102.5 which, for modern fuels, is slightly undersized leading to a slight flat spot in acceleration from low revs.  To eliminate this fitting a 107 jet is recommended.

The secondary jet is easily accessible at the base of the fuel bowl but the primary is a bit more complex.   The first step is to take the top off the carburettor, with the elephant’s knee (air intake pike) removed there are six flat head screws – one of which holds the choke cable in place – and the top of the carburettor lifts off.  As the jets are at the bottom of the bowls they will need any residual petrol in them removing.

Interior of a 2CV carburettor

Now comes the tricky part.  On the back right (as you look at it when standing in front of the car) corner of the carburettor is a 12mm bolt head – this is the access port to get to the primary jet.  With that bolt removed there is now a head on approach to the primary jet – shown arrowed here:

Interior of a 2CV carburettor showing primary jet location and access

The jet has a slot cut in it for a flat head screwdriver which needs introducing through the access port.  Fortunately in my tool box I happened to have a long electricians’ screwdriver that could have been specially made for this exact job as it extended clear of all the obstructions in this area and made this job much easier than I was anticipating.

Using a long screwdriver to unscrew the primary jet from a 2CV carburettor

With the jet unscrewed it will need removing from the carburettor.  As it’s brass the traditional use of a magnetic pick-up isn’t an option so I found a cocktail stick worked well as it wedges in the middle of the jet without damaging it and holds it just enough to withdraw it.

Using a cocktail stick to remove the primary jet from a 2CV carburettor

Fitting the new jet is, of course, the reverse of removal – making sure to reconnect the choke cable when replacing the top of the carburettor.

When everything is buttoned back up check the car starts and runs – it will probably need some cranking to re-fill the carburettor bowls.  Then, when the engine is nicely up to temperature the idle will need re-setting.


2CV Bump Stop Replacement

When replacing Judith’s chassis we had to go with the front bump stocks that were on the shelf. These use hold the rubber onto the mount with folded metal [shown on the left below] which isn’t the best method (although it’s cheap). The better option are the bonded bump stops from ECAS [shown on the right].

2CV friction fit bump stop on the left, bonded bump stop on the right.

This borne out by the fact that the near side (why is it always the near side) rubber had fallen out on the old bump stop.

2CV friction fit bump stop on the left - missing the rubber, bonded bump stop on the right.

Access to the bump stops is pretty easy, with the front of the car jacked up the swing arm clears a reasonable amount of space and, once you’ve worked out the best angles of attack, I found they came out with minimal persuasion – although a small pry bar was really helpful with this.
2CV front near side bump stop mount on the chassis

With them coming out so easily, fitting was the reverse of removal: finagel the bump stop bolt into the hole in the chassis plate and do the nut up to the standard torque setting of FT.



Replacing a 2CV’s oil feed pipes

Being an air/oil cooled engine the pipes that feed oil to the 2CV’s cylinder heads are a key part of the system. They take oil fresh from the cooler and distribute it to the cylinder heads where it passes round the exhaust valve sleeve to cool it before entering the rocker covers to keep that area well lubricated, then returning down the push rod tubes to the sump.

The factory fitted steel pipes which, as they carry hot oil and are right at the front of the engine immediately behind the cooling fan, are somewhat susceptible to rust. When carrying out previous work I had noticed that there was a lot of surface rust on them but there’s no way of knowing how structurally compromised they were – and the consequences of a failure would be spraying high pressure oil onto the hot cylinder barrels, a situation that would be classed as far from ideal. A preemptive replacement with new, corrosion resistant, pipes was thus in order.

New copper-nickel 2CV oil feed piples

Whilst replacing them “only” involves three bolts, those bolts are located behind the tinware, which in turn is secured through the front engine mounts. And it’s behind the headlight mounting frame for good measure.

2CV with bonnet and wings removed showing engine

Removing all that lot falls into the category of “not technically difficult but laborious and time consuming”. However, once it’s done, access to the feed pipes is very good.

2CV oil feed pipes highlighted on an engine with the tinware removed 2CV oil feed pipe cylinder head mounting

Removing the three banjo bolts (taking care to track which one came from which location as the one on the block is different to the ones on the heads) allows the pipes to lift off cleanly. Some new copper crush washers that came with the pipes were fitted, these are one – folded – spectacle type piece which are much easier to fit than individual washers that were used on the original.

The banjo bolts were refitted and tightened to a torque of 11 Nm (8 ft lbs) – being steel bolts going into lumps of aluminum this torque is both low and very important to observe. (It’s also less than the lie of 13 Nm printed in the book of lies Haynes manual.)

Whilst you’re here…

Bolts and nuts

With the tinware off it was a good time to do another job whilst the access was good: replace the manifold seals. (TL;DR: unbolt the manifold, lift it up, replace the seals, then bolt back on.)

In order to do that the manifold had to come off which made it a good time to do another job: re-torque the heads. (TL;DR: slacken off the head bolts then re-torque per the manual.)

In order to do that the rocker covers had to come off which made it a good time to do another job: replace the rocker retaining bolts.

After doing that it was a good time to do another job: adjust the valve rocker clearances.

Thanks

Thanks to TomB engineering and the Kung-Fu Panda for their invaluable help with this job.