Cracked Coil
My sad news is that Syd (one of our mechanics) has decided to return to the UK after more than 25 years in SA. He inherited some money and his wife qualifies for a British pension. This will make the transition easier. He will still be available to us as a consultant. The truth is that crawling round under cars, especially on winter mornings, is fine for a young man, but loses its appeal when you get older.
Luckily, I found a young mechanic, trained by a friend of mine, who wanted to get out of the city, and he has taken Syd’s place. Within days, we discovered that he had a wonderful sense of humour. This made the change easier for us. His name is August and when I asked him whether he was named after the month or the emperor, he gave a hearty laugh and replied, “The Roman emperor, of course.”
Soon after August started, a Fiat Bravo broke down quite close to our workshop. At the time I was in the spares department at the rear of the workshop and the first I heard of it was when August rushed in to inform me that a man with a moustache like a stasiebesem (station-platform broom) wanted to speak to me.
Stasiebesem’s dress and manner of speech left us in no doubt that he was a Brit and the car’s number plates confirmed that the car was also a visitor to our country. One of the front suspension coil springs had collapsed and we had to tow the car in.
It seemed like a clear case of a going too fast over the shocking dirt roads that we have in this part of SA, but August, who by this time had put the car on stands, pointed out that the springs looked very rusty for a car that showed only just over 30 000 km on the odometer. Springs normally get some kind of coating at the factory, but in this case there was no sign of it.
While ordering parts, I decided to speak to the workshop foreman at the Fiat dealer in the nearest big town, and he confirmed that this model does not have a reputation for breaking springs in South Africa, but that it happens a lot in the UK for some unknown reason.
I then e-mailed Syd in the UK and asked him to do a spot of research, while August got on with the job of removing both front suspension struts. You never replace only one, because the other one will also be weakened.
Syd’s reply was absolutely fascinating. The British AA had discovered that by far the majority of breakages occurred in April and May, at the start of the British summer. Germany showed the same pattern but very few breakages occurred in countries with mild winters, like Spain and Italy. Further investigation showed that the salt solution sprayed onto the roads during winter in cold countries cause a condition known as hydrogen embrittlement. Electrolytic action between the salt and the iron generates free hydrogen atoms that enter the steel and cause microscopic cracks that tend to weaken the springs. This process needs time to spread, which is why damage done in winter only shows up a few months later.
Broken Leaf
Many farmers are very capable when it comes to fixing simple mechanical objects, but sometimes a little theory also comes in handy. Take the case of Oom Hansie Holtzhauzen (no, I’m not going to mention his nickname!) of the farm Mooimeisiesfontein. His one-ton Toyota bakkie was often expected to carry a great deal more than one ton, so he modified the rear suspension. He combined the leaves from two old springs that had been lying around and the leaves from the existing Toyota springs to make up two springs that were considerably stiffer than the original parts. For a while the arrangement seemed to work but after three months the main leaf on one of the springs broke.
He brought the bakkie to us, and the general opinion in the workshop was that the springs were simply overloaded. But I reserved judgment. The springs looked a bit unusual because the lengths of the leaves no longer tapered off gradually at each side, but showed a jagged edge. This meant that the carefully calculated leaf lengths that ensure a uniform stress distribution throughout the spring have now been rearranged.
The rebound clips were also missing. They tie the leaves together on each side of the central clamp to ensure that they all take part in the action when the spring rebounds. The extra leaves, as well as the missing clips, tend to increase stress levels in the main leaf, with the result that a breakage was a strong likelihood.
Oom Hansie admitted that he had left the rebound clips off because once the extra leaves were added, the clips were too small. He thought that as long as the spring clamps were tight the clips would not have any work to do. I had to explain to him that the correct procedure would have been to get a spring service centre to fabricate stiffer springs.
