Fearless fording
Page 32
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THERE WERE two news items in the March 16 edition of CM that I wish to comment on Page 22 contained an article on the 4 X4 Bedford van and the comment was made that this particular CF was equipped with automatic transmission, a feature of which the writer "heartily approves of on 4X 4s".
I would consider that automatic transmission is suitable where the vehicle is nor mally driven only over rough ground or in muddy conditions and is always within reach of outside assistance.
I do not consider it suitable for cross-country work where deep rivers have to be forded or for work in isolated areas where the vehicle and crew are very much on their own.
I have owned two LandRovers — one a diesel, one a petrol — and have travelled throughout the Middle East and northern Africa, and whenever deep water needed to be negotiated, I usually fitted on a rubber exhaust-pipe extension to prevent the water from flooding back up the exhaust.
With normal transmission, however, it is possible to over rev the engine and slip the clutch, thereby obtaining the necessary pressure to force the water out but severely limiting the speed of the vehicle to that suitable for crossing a rough river bed.
I had never realised the importance of this until last summer when I spent a holiday in Iceland and hired a Chevrolet Blazer K5 to tour the interior.
This vehicle is presently being
marketed in the UK by GMC under the name "Jimmyand
as a 6ft Bin-wide, 5-litre automatic transmission crosscountry vehicle, the ride is sheer luxury and it offers more space and comfort than the Range Rover.
The ride in this vehicle can only be described as superb and tireless, but when we had deep rivers to cross, the limitations of automatic transmissions became obvious only too quickly. One particular river — the Fjordungskvisi — was something like 150 yards wide at its fordable point and about 2ft 6in deep. Being a glacial river it was turbid and it was, therefore, impossible to see the bottom. Wading in first was impracticable because the power of the river was such that a person could not stand up against it The fact that this was the safest and most practicable point to cross the river; having already been determined the only way to get across was to drive in as far up-river as possible and then steering the vehicle in the direction of the stream, drive from one sandbank to another breathing a sigh of relief every time that the vehicle came out of the water with its engine still running.
It was not possible to drive across the direction of flow because the current was so swift that it would have turned the vehicle over.
The engine had to be revved up high to prevent the water pouring into the exhaust, but as it is flat possible to slip the clutch on an automatic, we were forced to cross the unknown bed at a far higher speed than desirable.
Had we not had factual information that there were no rock shelves at this point, it would not have been possible to cross the river with an automatic vehicle at all, whereas with a manual transmission vehicle the crossing could have been undertaken in a more sedate manner and with minimal risk to engine flooding and suspension damage.
Another problem came when negotiating an extremely muddy stretch of track.
We did very well until we got to the middle, when the engine suddenly stalled and showed no interest at all in restarting. I was not too worried as I knew that there was a four-wheel-drive bus about half an hour behind us and this vehicle eventually pul led us out and the event was recorded on about thirty cameras, but of course the automatic Blazer could not be bump-started and it was than that I realised just how vulnerable we were.
The engine was eventually re-started and we continued on our way, but it was necessary for us to keep to "recognised tracks" for the duration of our stay rather than roam completely wild. A manual transmission vehicle would have been a far better proposition.
W. A. SHARP, Ingatestone, Essex