Tuesday, November 17, 2009

Things That Go Bump...

After returning from our expedition to the Granite Belt, I noticed a distinct tinny rattling noise which emanated from somewhere to the rear of the car.

It sounded like it was coming from the boot, and I found it to be a great source of irritation.

MX-5s aren't supposed to make tinny rattly noises. They're supposed to go "Zoom-Zoom" not "plink-plink".

I began to try to identify the source. It wasn't the exhaust system. After risking third degree buns, I discovered that it was attached as per specifications.

Next I took all the gear out of the boot (space-saver tyre, wheelbrace and jack). It looked as if the wheelbrace was contacting the jack in its cradle, so I packed a piece of towel around and between these two items. It made no difference at all. Plink-plinking continued.

Because the noise began to be heard after our Granite Belt trip, I racked my brains (this didn't take long) to think of anything unusual we did on this trip. Apart from drinking a little bit more red than usual, I was unable to recall anything significant. In any case, the quaffing of red wine and driving the MX-5 have always been mutually exclusive activities.

Then I remembered. We had to pack the boot pretty tightly. At the top and rear of the boot cavity are two very slim torsion bars held in place by a plastic clip.

A close inspection showed that these two skinny rods had separated from the plastic clip, and were merrily "plink-plinking" every time the car hit a small bump. Stuffing soft gear into the boot to the brim must have dislodged them.

The remedy was simply to put them back in the clip.

Hopefully this will help save someone else a fruitless search. It's back to "Zoom-zoom".