About two weeks ago, we experienced a strange incident. We were lucky: it happened at the entrance to our driveway and there was no additional damage and no injuries. At 55 mph on a highway, it could have been a disaster!

What Happened?

The car involved is an older Lancia Ypsilon (if you are not familiar with this, it is an upscale Fiat 500) that we were borrowing from our garage. The tires are new. The front suspension is based on coil springs with the shock absorber inside the coil, and (unknown to either the garagist or us) one of the springs developed a crack over time – it was not visible because the spring is covered in a plastic wrapper to protect it from salt corrosion in winter or beach driving. The problem occurred as we drove into the driveway, and it gave the impression that we had driven over a stone about the size of a basketball. Your mother was afraid that a person was under the car, but when I looked, there was nothing there – no stone and no body – but the tire was flat. We moved the car farther inside the driveway (less than 100 feet) – still sounding terrible!

What had happened is that the crack in the coil spring had corroded and the spring broke about six inches from the lower end. With the weight of the car on it, the spring spread and jumped over the lower support. The broken piece fell off (I found it in the driveway) and the spring rolled around to puncture the tire. The pictures below show what had resulted from this.

Thought this might be interesting.

Dad