POST 36 AUGUST 2012 IGNITION SYSTEM & USB PROGRAMMABLE DISTRIBUTOR

By the end of this month that scary engine start up moment will be imminent with only the exhaust system, cooling and ignition left to fit.


In close to fifty years of driving old cars, I would say that nine out of ten problems I've encountered on the road have been electrical and often ignition related.  Back in the sixties, even brand new cars had problems, especially on cold wet mornings when they were reluctant to start.
With this in mind, I'm keen to ensure that my electrical and ignition installation will never give me cause for concern.  It would also be good to see a pristine 1950 engine bay.  This competing requirement will inevitably result in some compromises, but original HT leads and plug caps would be good.  The downside might be interference to my proposed DAB radio installation, electro magnetic interference upsetting my electronic ignition system or RF noise locking up my neighbour's digital TV's as I pass by.  I really don't know and can't find any one that does, so it will be a case of try it and see.  Fortunately I have access at work to a Spectrum Analyser which will display whatever nasty stuff is being radiated and provide precise data relating to the effect on digital radio and television signals.  I'll let you know the outcome.

Cap, conduit and HT leads not quite as original and needing
some attention

XK's for the first few years had the HT leads routed under the carburettors and around the back of the engine leaving the front uncluttered.  It was not until 1953 that they were routed over the cam cover, possibly for some technical reason or maybe just to save a few pence on a couple of yards of HT cable.  Again, no one seems to know.  As a very early 120 my car would have benefited from that original design and in the absence of any good reason to revert to the later layout I adopt the original route.  To minimise the possibility of cross firing between leads (one of several reasons mooted for the change) I run them in an aluminium tube with a central polypropylene rod and original Bakelite spacers to keep them separated.  The tube is heat insulated from the engine with a calcium silicate sheet.

Original HT lead conduit cleaned up beautifully with black
boot polish.  Note polyprop rod to keep leads separated.

Neat solution to route leads under carbs

Note red 'Champion' labels on plug caps.  Not sure if they should be there. 
Definitive answer for a December 1950 car anyone? 

To improve on the usual practise of simply relying on strands of wire pushed into retainers to make electrical connections, the HT lead copper conductor is carefully splayed within the brass connector to the distributor cap and soldered in place.

Centre copper conductors splayed and soldered to brass connector

Next consideration is the distributor.  I have over the years had many a disagreement with the Lucas unit in its various forms and as its not particularly prominent within the engine bay, it will have a modern replacement.  I fitted a 123 Ignition distributor to my Frogeye around three years back and have never touched it since.  The very latest version is the 123 Tune with a USB port to connect to a Lap Top and programme in whatever curves you want.

Superbly engineered 123 Ignition 'Tune' distributor with USB
 port to programme your choice of advance curves.

The software to run this is downloaded from :  http://www.123ignition.nl/downloads/software/123Tune/ 

Running the programme, the first screen displays a very comprehensive dashboard with clocks for RPM / Crankshaft advance, Coil current, Distributor temperature, Vacuum and a timer to compare acceleration between two pre-set RPM points.

The second screen allows you to select seven points of crankshaft advance and seven points of vacuum advance / retard.  Each series once selected can be saved to file.  The distributor is connected via a USB lead and two 'curves' selected and downloaded into it.  It is possible to switch between them by applying 12V or 0v to the distributor's yellow lead.

The XK workshop manual has sufficient information to allow you to emulate the original setting for the Lucas distributor or you can put in your own.  You can even play about with them on the road, using the timer to compare acceleration between settings, but only after confirming that you are a passenger and not the driver, a neat touch.  If you happen to have access to a rolling road and dynanometer then you could really have some fun.
I had the benefit of following on from friend Tony Hamnett who fitted one to his 120 a while back and emailed me a whole series of curves taken mostly from the 123 Ignition website and tweaked for his particular application.  I simply selected the two he found best, imported them and downloaded them into the distributor.
My most likely application for the two settings, given the shortage of 99 Octane in this part of the County of Yorkshire (12th in the Olympics Medal table or top by a very long mile on a population / medal basis) would be to switch between curves optimised for high and low octane fuel.

Heat shrink nicely finishes of caps and will keep moisture out

On the recommendation of a couple of respected enthusiasts, I fitted a set of Iridium needle point plugs to my 140 about eighteen months / 7000 miles back and its run like a sewing machine ever since.  They are quite expensive at around a tenner each, but so far show no signs of wear so they're naturally included in the 120 spec.

Iridium needle point plugs - probably the best present an XK could have

From an appearance stand point, the end result is just about as good
 as I had hoped for

So that pretty well ties up the ignition system, all done with great care and attention, and I have absolutely no doubt that when I switch on the ignition and press the starter button for the first time - it won't start!


Miscellany
Autobodycraft, the company doing the 120 body, staged their own charity Motor Show on Sunday 12th August.  More than 100 vehicles were on display, 1500 people attended and over £5,000 was raised.

Great example of Yorkshire humour

Rat car with monster truck turbo diesel

Next Post beginning of September

POST 35 AUGUST 2012 NO MORE BOOT LID BLUES

The saga of the boot lid could fill a couple of books all by itself.  To recall.
It was missing along with many other parts when I bought the car back in 2010.  I did eventually acquire one which had had the bottom third of the ash frame replaced, but when offered up to the car, the overall shape was wrong.  I returned it to the supplier along with profiles cut from hardboard showing the exact shape required.  It was duly reworked and returned and a trial fit confirmed that it was now fairly close to being right.
However, close inspection (a little late in the day I will admit) showed that the aluminium skin was secured to the frame in many places by steel nails. Body shop man Alex was less than happy with this and I was sent packing yet again, booted out, boot lid in boot so to speak to find a solution.

Lid No 1    Less than ideal skin, lots of holes and a few nails.

 I allocated a whole day to resolve this and played around carefully removing the steel nails and replacing them with specially made (by me) aluminium pins bonded into the ash with the intention of welding the heads to the skin. After several hours of prating about, it became very clear that I was pissing in the wind (I apologise for the language but it best describes the mood) and went home.
The following day, a Sunday morning I am back with renewed spirit, take afresh look at mess I've made and decide to do something else instead. 
Contemplating the purchase of a complete new lid at circa £3000, I recall a conversation I had about a year back. A friend of a friend said he may have one but it was probably beyond repair. A couple of phone calls and an hour later I'm in the garage of Rob Hind at Sadberge and looking at a rotten wood frame with perfectly good skin.
If I can fit this good skin to my OK-ish frame that might be be the answer.

Lid No 1    As well as repaired bottom frame, steel strips are rusting

Back at the workshop and further investigation indicates that opening up the wrapped around edges of the skin will be difficult.  I try annealing first but can tell that anything more than slightly opening the seam will end in tears.
I eventually manage to remove the rotten frame from the skin and and determine that it should not be beyond my wood crafting skills to fabricate a whole new frame to fit into it rather than use the repaired one.  This massive misjudgement is dealt with in detail in post 29 (Boot Lid abandoned). 
As outlined in this post, after many hours of wood wasting, I eventually find and order up an exact copy of the original frame for £250.  As requested, it is delivered in pieces enabling me to build it into the skin.  I am now back in my comfort zone and work proceeds apace making up new steel strips to screw onto the frame and slip into the aluminium skin.  The frame is temporarily built up with hinges, handle and catches and a trial fit looks promising.

First trial fit of temporarily assembled boot lid frame looks good

Next I need the aluminium trim pieces to fit around the edges and Contour Autocraft come up trumps again with a really good fitting set.
Having established that the frame is fundamentally the correct shape I prime and refit the steel strips, inject Tiger Seal into the folds then assemble the frame into the skin.  Crimping the skin back in place with a special tool borrowed from Alex was very easy, but the addition of the sealant means almost certainly that it will never come apart again. 

Edge crimped onto steel strip and sealed in with Tiger Seal

Ash and softwood laminated frame match the rear end shape exactly

Back to the body shop and Alex tweaks the fit, bashes it around a bit then skims and shapes it before giving it back to me.  All that's left is for me to glue it all together and fit the corner pieces supplied with the frame kit.  Its finally taken back to Alex who is at last satisfied that once painted, it will look perfect and more importantly stay looking perfect.  My final job will be to fit the inner plywood panel but this will be done from underneath with the boot lid fitted, to ensure that no twist occurs. 

Rare view of boot lid from petrol tank location.  Ply panel will
be fitted from here to ensure no twist occurs.

Once screwed in place this adds an unbelievable amount of stiffness to the whole boot lid structure.
Just for fun I tap into our companies small works costing programme for jobs based on time and materials.  I put in my time spent, material costs and associated travelling - three time to Newcastle and twice to Harrogate.  With an hourly rate of £37.60 a nominal overhead cost and mark up it totals up to £3,267.27  There is a moral in there somewhere. 

Miscellany - related topics

Croft Nostalgia Weekend
Preceding the Croft Classic Weekend I was invited to a Press Day along with a few other JDC members to help promote the event.  It turned out to be a thoroughly enjoyable day with plenty of opportunity for track action and quite well organised compared to last year.  BBC regional News gave it a half minute plug in the evening and my 140 appeared for a nano-second at the back of a bunch of cars on the track and a few seconds later at the front - if only!


The Croft Nostalgia event is a fabulous weekend with all the atmosphere and a good deal of the spectacle of the Goodwood Revival, but without the huge crowds. The BRDC have a full programme of classic racing and everyone has access to all areas including the paddock. At £25 for both days its quite a bargain. No doubt it will cost a little more next year.

Set up 1955 Photo I took end of July at Croft Press day

Trailer mounted Rolls Royce Griffin V12 ticking over. Only a couple
of wheel chocks stop it shooting off down the runway when opened up.

Next Post mid August