Road and workshop
Page 51
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by Handyman
Vehicle recovery: tricks, trucks and tactics (13)
• So far I have dealt with reasonably straightforward jobs. However, transport produces something new every day, and in due course you find yourself kneedeep in an unusually tough assignment.
I have in mind a recovery which did not at first appear a problem: an 8 cu.yd. capacity tipper was one of a number working at a river mouth, and operating along a temporary causeway of gravel and larger stones. Inland of the causeway was more gravel at least 10ft deep, seawards was river silt of unknown depth.
While the driver was out of his cab, and unfortunately with his engine still idling, the tip of the causeway fell away in a small landslide, and the vehicle slid or ran down into the river, which was at full tide at that time. Recovery was assumed to be a simple task and a local garage team was sent out to the site. It had to wait for the tide to drop to get a lashing out to the tipper; this was accomplished after obtaining some dwelling house doors from a demolition site three miles away.
The four-wheel crane coupled up, but made no progress whatsoever. The crane could not obtain a firm grip on the gravel and made not the slightest impression on the vehicle in the silt.
As a result the crane was withdrawn from the operation, and a slow but heavy Pioneer was called out. However, this unit was 26 miles away, and by the time its best pace of 16 mph brought it to the scene, the tide was on the turn.
However, the Pioneer was coupled to the existing lashing which was no more than two turns of a lin-cable around the chassis. The driver's first pull was futile. Two things happened: the Pioneer began to ride on the gravel, and then the cable began to squeeze the chassis frame.
A halt was called, as with no anchor point anywhere near, and no grip for anchor spuds, it was clear that the heaviest wrecker could not unstick the tipper singlehanded; nor were the lashings adequate if additional power was available.
So as the tide fell and the vehicle could be approached over temporary duckboards, a two-legged sling or trace was arranged at the junction of the chassis cross-members. This was a slow and dirty task for the chassis was submerged in silt so fluid that it could not be shovelled away. Next a double sling was made to a common bull ring, although it had not been possible to block the chassis as one would have wished, so a risk of sorts had to be taken to make progress.
Two part-loaded eight-wheelers were brought along and positioned on the safer gravel behind and to each side of the wrecker; these were shackled by chain to the front platform or cross-frame carrying the hauling winch, and lightly tensioned. Two of the heaviest double-snatch blocks were laid out—one was shackled to the wrecker and the other to the bull ring.
The winch cable was drawn out and formed in four large loops between the blocks, the cable end being shackled to the block at the ring. The cable was then fed through the four sheaves and the block latches closed and pinned. With 36 static tons as an anchor, and a 5 to 1 ratio heave from the winch via the snatch blocks, power was applied steadily to about quarter-throttle, at which point the tipper broke free from the grasp of the silt and was hauled to hard gravel.
The blocks were removed, as a straight winch pull could do the rest, and the bedraggled tipper was once more on solid ground, although unfit for work, as all its hubs had to be stripped out to clear the silt and salt water. Dif, gearbox and engine had to be drained and washed out, and the vehicle thoroughly washed and greased, not forgetting that a squeezed chassis had to be squared up. This, of course, was the result of the Pioneer making its first pull with the single lashing.
Although the recovery had finally been accomplished and the now decidedly grubby team could clean up, it could be said that a suck-it-and-see technique had in this instance turned out a little expensive overall....