THE CHALLENGES OF DRIVING – AND CAMPING – AT (REALLY!) HIGH ALTITUDE

Did you know: We typically think of water boiling at 100 degrees Celsius, even though this is only true at sea level. At 14,000 feet (4,267 metres) water boils at 85.5 degrees Celsius. To make water safe for drinking, technically the higher you go the longer you should boil it. In many countries this is more of a technicality since you can’t go high enough for it to make much of a difference, but in Central Asia you can!

Tajikistan’s Pamirs were always going to be a highlight of our journey across Central Asia, something I could just feel in my bones from the outset. The altitude that we needed to travel at – as high as 4,655 metres elevation – posed the challenges that I had anticipated, but also one or two that I had not. It was entirely expected when I found myself more breathless than usual working to set up camp around 4,000 metres, though I was surprised when I kept waking on the first night due to a sensation of suffocating. What was happening, or so I believe, is that my automatic ‘sleep-sized-breaths’ lacked enough oxygen at that altitude. The kids all seemed to cope just fine, and other than headaches on the first night Sylwia and I did too.

By going from one camp at 3,200 metres in Kyrgyzstan to the next at 3,900 metres in Tajikistan, we would appear to have broken an important guideline of not sleeping more than 400 metres higher than the previous night.

We considered that the time we had spent between 3,000 and 4,000 metres in Kyrgyzstan in the preceding weeks should assist with our quick acclimatisation to life above 4,000 metres in Tajikistan, and it generally worked out fine.

The dependable Mitsubishi turbo-diesel engine never failed to start… though it did so on the icy high-altitude mornings sounding rather like a 40-year-old tractor chugging slowly to life. Once warmed up it ran perfectly fine, other than some black smoke that’s not normally present, plus notably increased turbo lag; both symptoms of the thin air.

An unexpected issue arose when I discovered that my diesel-electric tent heater does not like high altitude; it began to encounter reliability issues much above 3,000 metres! Even though we reached the Pamirs weeks later than originally planned – autumn rather than summer – it can get cold above 4,000 metres at any time of year and as such I had hoped to rely more so on the tent heater. We experienced nights as low as minus 11 degrees Celsius, so this was something of an issue! What occurs is that the air/fuel ratio becomes skewed in the direction of being too rich, this owing to the thin air present at high altitude. Whereas the car engine is eventually helped out by the turbocharger kicking in to force feed additional air, the heater has nothing similar to aid it.

At the heart of my home-made tent heater is the same type of diesel-electric furnace commonly used to safely heat caravans and motorhomes. Ordinarily a consumer with a failed one of these units would be advised to take it to an authorised service centre for repair… that’s simply not practical on a trip such as ours though!

Time and experience have taught me that it’s hugely beneficial to acquire the skills to fix whatever may break yourself. I’d never repaired one of these, but there was nothing to lose by trying and everything to gain (the nights were cold!). Motor assembly off… glow plug out… separate combustion chamber from heat exchanger… and the issue was revealed. As suspected, the rich fuelmix had caused so much internal soot build-up as to choke off any possibility of ignition being achieved.

All that was needed was thorough cleaning and reassembly, which was good, however I failed initially to realise that as long as we remained well above 3,000 metres this was a process that I would find myself repeating daily. And all just to get a couple of hours of heat before it would fail again! Fortunately, this was only for the few nights we camped at such high altitudes and once back below 3,000 metres the heater returned to reliable operation.