Monday, 21 August 2017

Comical Flasks

 

Is there a Doctor in the house?

These two samples, though not quite the gruesome specimens they first appear to be, may be helpful in nursing 671 back to good health. 

It appears that fuel contamination is yet another factor in 671's heavy smoking. Taken from the filter bowls of the two brothers when (recklessly) I decided to change their secondary filters simultaneously, the sample of nice fuel on the left comes from 420 and the dark, murky fuel on the right, from 671.

Perhaps a kidney problem? 

In any case, I plan to drain and flush the fuel tank before the refurbished pump is refitted, and we can then test all the engine related work so far - which, by the way, we're now pretty much ready to do.

The mended 'python' is now back in place (further painting to be done in the vicinity) and the network of new fuel pipes - as comprehensive and impressive as the tube map - are all ready to go.

Meanwhile, while we wait for the pump to be delivered (by SUL coach, of course, during Kingsbridge Running Day), I'm about to begin work on 671's rear brakes - a task which fans of 270KTA.co.uk will be able to guide me through in their sleep, as it's now been 8 years since I last did it.

In readiness, 671 is now officially airborne, supported on axle stands and around a foot higher than nature (or Brislington) intended.
 
Unlike last time, I'm actually looking forward to finding out what state they're in...

And finally, burger fans will lament... 671 is no longer equipped with a towbar. This was fitted (appallingly) sometime around 2011 to enable the final indignity of towing a small trailer. I took great delight in removing this blight one Saturday afternoon, officially bringing to an end an era in which poor 671 had been treated as a circus mule. 


The cruellest of observers suggested that I should install it permanently at the front, but they obviously don't realise what a co-operative little bus 671 is turning out to be...

Tuesday, 30 May 2017

Deep Breaths

For those who fancy python wrestling without the risk, might I suggest one of these?


You'll find them underneath certain SUL buses - those built after 1964, and some earlier ones which were retrospectively fitted. What is it? You'd better read on...

This is potential cause number (3) of 671's white smoke issue, albeit the least likely, but a job to be done regardless. It's the exceptionally elaborate network of pipes through which air is drawn, cleaned and delivered to the inlet manifold of the engine. 

Perhaps less well known than the equivalent statistic about arteries in the human body, it's nonetheless true that if 671's air intake was stretched out end to end, it would actually cover ground from Minehead to Lynmouth and back - twice.

Now, a quick lesson in SU air intakes, for those who themselves gasp with excitement at such things: 

Early SU buses, and all SU coaches, were originally fitted with air intakes on the front roof dome. The air was drawn through trunking above the driver's head (hidden by panelling on the coaches but exposed on the buses), the sound of which made for a noisy cab environment when the bus was pulling hard. There was also no air cleaner to remove unwanted particles from the air before delivery to the engine. 

Western/Southern National modified its SU coaches to draw their air directly through an oil bath filter, fitted under the floor alongside the manifold - as exhibited by 420, whose original intake vent wasn't re-fitted when the dome was replaced on conversion to dual-purpose. West Yorkshire (and very possibly others) also fitted air cleaners to their SU buses; as we know the floor is lower in the SU bus than it is in the coach, hence the intake and cleaner had to be taken forwards where there was more space. Later SUs were built to this spec and as a result, 671 has this big long python...

More to go wrong! The rubber sections of 671's had collapsed, restricting the air flow. The air cleaner was full of muck. The end cone was rotten and in danger of breaking apart. So I thought it worth wrestling the python onto the bench.

A thorough clean of the air cleaner (ironic) and pipes followed, together with new hoses, elbow joints and clips. 


But what about that cone?


A moment of midnight inspiration made me wonder if any similar cones were made for tractors - you know those little musroom things that stick up through the bonnet? The answer was yes - but also an identical one, for a Massey Ferguson tractor.


A double result at just £20. Something else now ready to go back on...


... just as soon as the chassis is dry. I did mention I'm working on that, too?


Breathe deeply...

Thursday, 25 May 2017

Just The Start

"Where do you even start?"

Human beings are wired to ask this question whenever they see somebody else's unenviable task before them. Usually it's rhetorical, an attempt at driving home what an idiot they think you are for taking on such an impenetrable project. 

But occasionally they genuinely do want to know the answer.

When it comes to restoring a bus there are different philosophies on the answer. Much as I look forward to making a visual difference to 671 (which in its current state prompts the rhetorical form of the question quite a lot), this idiot believes it's best to begin with the vital organs: all the various components and control systems associated with the chassis, the engine, gearbox, hydraulics, brakes, steering etc.

So that's where I've started on 671. 

Work since January has mostly been allied to the engine which was suffering with a severe white smoke issue. There are several potential causes, and consequently several work fronts to be started, all of which 'need doing anyway' whether or not they solve this particular problem.

First of all, the fuel injector pump. Having replaced the diaphragm in the pneumatic governor last year, it became clear that, really, the whole pump needed an overhaul. Of particular concern was that the cold-start mechanism was locked open, allowing excess fuel at all times and therefore one potential cause of the smoke (1).


Briefly, the cold-start is a device that helps the engine to start from cold by providing extra fuel. When the knob is turned, it allows the rack inside the pump (which governs the amount of fuel being delivered to the engine) to spring forward to a position where it's enabling maximum fuel to aid starting. When the engine fires, the vacuum created pulls the rack backwards, the spring inside the knob returns it to its original place, closing off the excess fuel position during normal running. 671's cold start mechanism was mangled and a tiny (but crucial) spring broken.


With expert help from Sheppard Senior and parts from my two donor pumps (useful having a pump that's common to the Fordson Major tractor, no?...), a strip-down and rebuild has resulted in a fully functioning cold start mechanism, and injector pump.

With pump absent, I've taken the opportunity to fully degrease, prime and paint the top of the block and some of the surrounding chassis. 

Incidentally, this operation was interrupted with an operation of a different kind on 671's owner, meaning that the first and second coats of silver were applied while trying not to burst nineteen stitches in the upper-abdomen - but that's another story!

Six goes with Jizer, followed by four coats of paint, have resulted in a much brighter and well protected environment. 


Learning from my endeavours with 420, my preventative pipe replacement programme has been extended to 671. I've made replacements for all the main fuel pipes, which were quite worn and mostly fitted with potentially troublesome press-fit olives. They all now have neatly braised 'proper job' ends, like these two seen under construction.


I've also had a new set of injector pipes made. Once bitten...

All this is now ready to be refitted, at which point we can address potential smoke cause number (2), the timing.


Meanwhile, in a world of many simultaneous workfronts, I've already been grappling with potential smoke cause number (3)... come back soon to find out about that.

Remember, this was just the start...

Monday, 22 May 2017

Since We Spoke...

Active restoration of BDV 252C has begun...


In fact, I've been 'at it' in earnest for nearly six months and there's now much to report. During a few rare moments with clean hands, I'll do my best to bring you up to date via a series of posts that show you the various work-fronts in action and explain what's been making me so filthy.

The project has continued apace since January, when 671 was moved from storage into an area where it can be immobilised and worked on in relative comfort for the first stages of its restoration.

Last year's preparatory work on the electrics and pneumatic governor meant that it would now start on the button and tick over without either stalling or gradually revving itself into oblivion - both little interim triumphs.

During the move, it was rid (at last) of everything that didn't belong to it, not least the dozens of unwanted bus seats which previous owners had heaped inside it. The interior, whilst depressingly worn after years of neglect, is all there and has dried out nicely after its first few months 'in prison' (for this is how it must feel to 671 after a lifetime out in the open).


Since January I've been gaining momentum with at least a day a week, often two or sometimes even three, dedicated to on-site restoration. Much else for the cause happens in between those days - the sourcing of parts and other spendings of money - but it's those days which move things along.

And moving along things are. Join us soon to find out how... and what this is....


Monday, 22 August 2016

Man 1-2 Guvn'r


During my little 'facts of life' lecture on the difference between SU buses and SU coaches, there's one major difference I forgot to mention.

671's Uncle Trevor writes:
"... the floor on an SU bus sits directly onto the top of the chassis; you've lost the luxury of having a couple of inches above it that you get on an SU coach, and you'll find that it matters when you come to try to remove the injector pump (or, to be more precise, the pipes to the governor at the end, which you'll find are ... extremely fiddly and difficult to get to!)."

Very wise words from a man who's been there, face down on the floor of his own SU bus, West Yorkshire SMA 5.


I suspect Trevor's hands are as cut and bruised as mine have become during the struggle to replace the rubber diaphragm in 671's pneumatic governor. This is the part on the back of the injector pump (top right) which regulates fuel to control the speed of the engine.

On an Albion EN250 engine, this happens by varying the vacuum on one side of a rubber diaphragm, linked to the rack in the pump. This sliding assembly is spring-loaded so that its default position allows maximum fuel. When the engine is running, a vacuum is created which fights against the spring to pull the governer to tick-over speed; as the throttle is increased a butterfly valve in the manifold is opened which allows air into the system (reducing the vacuum). Thus, the assembly moves in favour of the spring and the fuel is increased - so the engine speeds up. When the diaphragm is worn or rotten, as 671's was, the vacuum is compromised and the engine tends to tick-over too fast and becomes harder to control.

The job itself isn't too much of a challenge, if very fiddly for two hands, but getting to the governor is a different matter. The bolts are just about accessible on an SU coach (I've done three of those!) but, as Trevor warned, the lower floor of the SU bus means that only angels and small children are able to find their way in. Being neither, I eventually managed to access the bolts from under the bus by blindly poking around with a socket on the end of FOUR extension bars, fed across the top of the gearbox from two bays back!

I'm an idiot.


As it happens the job was worth doing. 671's diaphragm wasn't too bad, but the special adjuster screw on the back of the governor (which allows angels and small children to fine tune the movement of the assembly inside) had been worn to an oval shape by years of hunting. Luckily, the Blue Peter of SUs, I just happened to have another one ready to go.

Refitted, there's much improvement - but guess what? That adjuster screw now needs turning and there's absolutely no way....

Unless... know any kids?


Tuesday, 26 April 2016

Little Jobs

I can't decide if this is a fine sight or a worrying one...


Not only was this the first coming together of the two brothers since 671 arrived, this was almost certainly their first meeting in over 40 years. They're likely to have encountered one another in the early 1970s, when both worked on Somerset routes around Taunton; one day, perhaps, we'll find a photo to confirm it.

For now, I'm quite happy with these ones, opportunistically taken in the yard during an essential move around. (Actually, it was deliberately arranged for pure indulgence - nice try, Sheppard.)


Followers of 270KTA.co.uk will know that preparations for the 2016 Penzance Running Day have taken priority in recent weeks. Nonetheless, I've completed a few little jobs on 671 to enable major work to begin in earnest soon. I've fitted a new set of batteries so that I can test the work I'll be doing on the engine (yes - it not only runs, but starts on the button!). 671 arrived with 'leisure' batteries fitted, designed to power utilities in a caravan and not really suitable for firing up Albion EN250 engines...

I've also investigated the excessive exhaust smoke issue (see the video for details!), and suspect that a combination of timing, poor adjustment of the cold-start facility and a worn diaphragm in the injection pump governor is to blame. Having sourced the necessary parts, these will be my first tasks to tackle over the next few weeks.
The keen-eyed will notice the awful make-shift rear number plate has been removed, enabling a template for new glass to be cut.  And, for the little it matters at the moment, it's had a good wash...


With a successful Penzance Running Day now in the bag for 420, it's time to get stuck-in. Seeing the mischievous smiles at the top of this post gives much encouragement and reminds me that, after quite a few 'little jobs', even really naughty SUs can eventually be tamed. My early impressions are that 671 may be a little more co-operative than (br)others have been along the way... but that's probably a dangerous thing to say.

After all, it's now two against one.

Tuesday, 5 April 2016

It's a Long Story...

I think I'd better explain how I've come to be writing this blog.

Regular readers of 270KTA.co.uk will know that my irrational love of the Bristol SU-type gets me into all sorts of trouble. Having helped to restore the SUL coach owned by my family since 1993, I bought another one of my own in 2009 and have spent nearly seven wonderful but calamitous years trying to tame it. Here I am in 2016 having bought yet another one to restore, this time an SUL bus. 

(Read a quick lesson on the differences between buses and coaches here.)

In this first post, I explain how the obsession began, despite the SU having long since finished in service by the time I was born. The SU coaches entered my consciousness by accident, at bus rallies and road runs, their pleasing lines and smiling 'faces' doing their own work to charm a schoolboy with a weakness for such things. The SU buses had to work a little harder to get themselves noticed, but only because there were very few in active preservation at that time. 

I'd seen them in books (he says, like an adolescent schoolboy describing how he'd first encountered the opposite sex). My Dad thought they were ugly, but I liked the look of them. Small and quaint, they had the same mischievous look as the coaches. And, like the coaches, they had a habit of lurking around in the background, puncturing the grandeur of the bigger, more purposeful buses.

The first SU bus I actually saw was this one, a long-term, decaying resident at the yard of W. Norths of Sherburn-in-Elmet (who also played a significant role in 671's continued existence, as you'll read in the potted history to the right). 
My Dad and I visited Norths a few times when I was 8 or 9 to find spares for our Bristol Lodekka. The SU was Western National 634 (348 EDV), although by the time I saw it there was nothing left to identify it. 634 was an instant hit with me, not just because it was an SU but also because it had no remaining steering mechanism which meant the steering wheel could be turned round and round with next to no effort. This was a vital feature for a nine year-old aspiring bus driver. 

I soon met (and drew) the SU buses at Colin Billington's place in Berkshire, as well as Trevor & Shirley Leach's beautiful red West Yorkshire example - by which stage it was too late to stop the growth of what has been an ambition ever since: to own one.

The first I knew of BDV 252C (671) was this photograph. I bought this quite soon after I started collecting photos of SUs (as an addict would) in the early 1990s and was excited to see there was still a Western National SUL bus in a good state of repair. 

A little investigation showed it was privately preserved in the North of England by a father and son team, Dennis and Dave Say of Yokefleet, assisted by Dave's future wife Christine and, later, Dennis's partner Margaret. I collected many other photos of it whenever they turned up, both in service and in preservation, the latter always showing it turned out well and confirming it was in safe hands.

Dave Say has very kindly shared with me some tales of their time with "the happy bus", as 671 was known, and I'll be posting these in due course as a tribute to the vast contribution the Says made to 671's survival. 

All went quiet from 671 in the early 2000s when it was sold on to a truck enthusiast who required a bus to ferry his friends to shows. The new owner wasn't actively engaged with bus preservation so 671 quietly disappeared from the scene and we interested parties all lost track of its whereabouts. 

Concern was mounting for its continued existence until, in around 2012, it emerged looking like this...
... a far cry from its cup-winning days with the Says. There was concern for its future among enthusiasts as it passed between short-term owners, deteriorating further each time. 671 had become an emergency.

Twice before I've narrowly missed out on buying 671. On both occasions it was sold for quite an excessive price given the amount of work required for the restoration. First time it moved to Bath, where the owner promptly listed it for sale on eBay, a dangerous marketplace for historic vehicles. Despite a realistic but generous offer from me, it was sold again to a new owner in Somerset. 

Having established contact, I was kindly given first refusal when the time came to sell 671 - and after the anguish of missing out twice in recent years, I didn't dally around!


The sale was agreed on 13th (oh gawd) January 2016 and, after a preparatory visit to bleed the clutch and reattach the prop-shaft, we collected my prize by low-loader on 4 February 2016, my long-suffering Dad at the wheel quoting the Laurel & Hardy phrase "Another fine mess you've got me into"...


Highlights of a memorable but smooth journey 'home' can be enjoyed in the video below.


Now safely home, the scale of the restoration task can be easily assessed. It is huge, though I'm surprisingly undaunted. That's not because I'm either naive or arrogant (our other vehicles kicked any last vestiges of those traits out of me years ago) but this time I want to take my time. I'm lucky enough to have other buses I can drive in the meantime so, unlike previous projects, I'm under no immediate pressure to have 671 on the road.

Instead, the priority is to enjoy the restoration and do a thorough job over the next few years. Whatever horrors we find - and, trust me, there will be some, if not many - we'll deal with them gradually and watch as it slowly comes back to life.


And that's why I'm writing this blog - enjoy watching...