Auto Gossip

Press, Volume CXI, Issue 32553, 12 March 1971, Page 15

Auto Gossip

by

A.J.P.

Tiring faults Vibrations and noise are two of the most tiring faults a car can have when it comes to long-distance driving, and also to long distance journeys as a passenger. Some cars which are very acceptable around town are less than acceptable on trips just because of the noise level, in the same way as a holed muffler (assuming it doesn’t gas you) may be bearable in town, but you know what it’s like after 250 miles on the open road. All of which, in my mind points to two things: the importance of finding out just how noisy a car is on the open road before you buy one, and the importance of doing a noise and vibration check before long trips in the family vehicle. Wheel balance Vibrations are almost invariably caused by faulty wheel • balance, although worn steering and suspension parts—much more expensive to remedy—can also . cause this trouble, and so can a bulge in the casing of a faulty tyre. And a slightly worn suspension, of course, will really amplify the vibration from out-of-balance wheels. With higher speeds and smaller wheels, I think more motorists today appreciate the importance of wheel balance, but many forget that a wheel J that seems perfectly bal-1 anced at city speeds mayi cause terrible vibrations! when the car is travelling! 20 or 30 miles an hour faster. Rear, too Again, many motorists do ; not seem to realise that a badly out-of-balance rear, wheel can cause as much! unpleasant vibration as a badly-balanced front wheel. The difference is usually' that the front-wheel balance' fault is felt easily through! the steering, while the rear wheel trouble is felt mainly; through the frame of the car. Balance, once remedied, can easily go wrong again, too; usually because of a puncture repair, or because a balance weight has been thrown off. Propellershaft and universal-joint disorders can often be mistaken for bad rear-wheel balance, and vice versa, so the vibration problem is not always as easily solved as one might think. All modem cars are sensitive to wheel balance, but some far more so than others. Felt and fur Wheel-balance is a task; for an expert, but noise is a problem most motorists; can do something about: themselves. Undersealing is obviously a great help, but considerable reductions in noise can be achieved by

the judicious placing of heavy felt, or similar material, on the floor of the boot, under the rear-seat squab, under carpets and against bulkheads, and even under the bonnet lid. But if you glue anything under the bonnet, make sure it is firmly fixed and well clear of anything that could set it alight Interestingly enough noise reduction is one of the major advantages of a car-roof-covering process now being offered to motorists in Britain. The roof is masked off, coated with a special glue, and elec-trically-charged nylon fur is fired at the glue, giving the roof a tight-packed nylon coat. Apparently the finish is easily washed, and is so durable one can even scrub the finish with a wire brush without damage. Oh, and when you are trying to reduce the noise-level, don’t forget all those tools lying about in the boot, will you?