Thursday, 9 December 2010

A Winter Warmer

The keen eyed* will have already observed that a new Winter banner has arrived on the blog, marking not only the coldest week of the year so far, but also twelve months since 270 KTA was delivered to her new owner.

It was Sunday, 6th December 2009, just days after I'd agreed to buy her, that she arrived from her previous home in Cornwall behind a tow truck.

I remember arriving in a half-light to find her ticking over impatiently in the yard, her front panel missing and smelling strongly of leaking fuel, and the mixture of elation and horror in realising it was now over to me.

Who would have believed that twelve months on, the elation would still be just as strong (as is, at times, the horror.. and come to think of it, the smell of leaking fuel - but we'll say nothing of those). My aims for a return to the road within weeks of that day have proved naive, but there's been much progress, and an awful lot of learning to be proud of.

And proud I am, of us both.

We eventually put her inside, before spending the rest of the evening in darkness trying to revive the tow truck, which had itself conked out. I chose not to take it as an omen...

*Those with even keener eyes will observe that my Winter theme has called for some artistic licence. The SU on the right of the banner is in fact 273 KTA, seen crossing snowy Dartmoor sometime between 1969 and 1971. The terrain is just like that which her sister will need to conquer en route to MOT next year. As for the weather, well...

Thursday, 2 December 2010

COLD AIR & VACUUM

If you think you're cold, spare a thought for our six-wheeled friends who are currently braving a relentless run of sub-zero temperatures. Tonight in the South Hams, 270 KTA and friends will be huddling together for warmth in surroundings of -8 degrees C!

And if that hasn't melted your heart, spare a thought for those of us who have been working on them in the arctic...

Here I am wearing three jumpers, two vests, six socks and Compo's hat (from "Last of the Summer Wine") last weekend.

After a couple of weekends storing up heat, I've begun work on my list of jobs-to-be-done-before-we-go-anywhere (to appear here in full shortly). The aim is that, once I've worked through the list, I should not only have cured all the outstanding issues which have so far hampered attempts at an MOT, but I'll also have performed a good deal of preventative maintenance which seems to have been lacking since... well...

First and foremost, I've been tackling a problem which seems to be at the heart of the braking issue. Comparing the vacuum gauge to that on her sisters during the Kingsbridge weekend, 270 KTA is having great trouble building up vacuum.

For the uninitiated, whilst the brakes on an SU are hydraulic, they are assisted by a servo which is operated by vacuum. Without the servo, or the vacuum, the brakes will still operate but with limited force, and are pretty useless on the road. Sounds familiar, doesn't it...

After weeks of isolating sections of the system in search of a leak, I concluded that the exhauster itself (which creates the vacuum) must be at fault. Mercifully, Colin Billington was able to provide some spares, and last weekend I became the world's leading expert in changing Bristol SU exhasuters... in the cold.

With a replacement exhauster fitted, the gauge reached levels of vacuum never before achieved, and with full vacuum the brakes worked really well. However, a trip up the drive revealed that vacuum was still too slow to build...


It's possible that, whilst the replacement exhauster is more effective than the original, it's still not quite up to the job, and with that in mind I'm going to try a third exhauster before drawing too many conclusions.

Though I might wait a few days for slightly warmer weather...

Sympathies also to SMA 5, Trevor Leach's former West Yorkshire SUL bus, who is currently snowed in "in a cold, wet building on a farm in North Yorkshire". Your South West cousins are thinking of you and rubbing their tyres together...