Oom Matewis Pansegrouw has been teaching mathematics at the local high school for as long as anyone can remember. He has twice tried to retire, but was called back every time due to the current teacher shortage.
Many years ago, his name, which is the Afrikaans equivalent of Matthew, was aptly mispronounced by a schoolboy, with the result that he became known as Oom Matesis (an archaic Afrikaans term
for mathematics).
He has a Nissan 1400 bakkie of indeterminate age, but we seldom see it because he does most of the servicing. The other day, the Nissan refused to start and Oom Matesis asked me to help. I sent Japie, our apprentice, to his house.
Japie reported that, when the starter switch was activated, he could hear the starter motor spinning without engaging the ring gear teeth. He knew, when the starter solenoid was engaged, it would slide the starter pinion towards the ring gear. As soon as contact was made with the ring gear, the solenoid would bridge a pair of contacts and energise the starter motor. He assumed that the Bendix drive which causes the pinion to rotate while it is moving towards the ring gear was covered in gunge. This would prevent the pinion from moving to the end of its travel, so he removed the starter motor and cleaned the drive. They then tested the motor by connecting it to the car’s battery and saw that the pinion shot forward like it should. But, when the motor was re-installed, there was no improvement. The starter still whined away without rotating the engine.
Japie brought the starter motor to the workshop and asked August to have a look at it. A smug smile spread across his face while he casually announced that the over-running clutch had failed. “The what?” asked Japie. “The little gizmo that prevents the starter motor from over-speeding when the engine starts,” said August. He then showed Japie that the pinion was quite happy to rotate in either direction, whereas the one-way clutch should have allowed rotation in only one direction. A new one-way clutch was ordered and fitted the next day.