It pays to check your car regularly

Oil becomes contaminated with use and dirty oil can play havoc with hydraulic tappets.

Oil becomes contaminated with use and dirty oil can play havoc with hydraulic tappets.

Published Sep 28, 2012

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It’s strange how apparently sensible people sometimes fail to practise what they preach. For example, a man who runs an old Escort CVH never has it serviced, but is fanatical about getting his daughter’s Golf done at regular intervals.

Therefore, I was surprised when he called on me complaining of a rattle which showed itself when the engine was fully warmed up and appeared to be coming from the top of the engine.

Someone had told him the noise came from the hydraulic tappets.

Engine oil becomes contaminated with usage and the oil in this engine had not been changed for a very long time. Really dirty oil may play havoc with hydraulic tappets, so an oil and filter change was carried out and I treated the engine to half a tin of upper cylinder lubricant and took it for a longish test drive.

The Escort ran well enough and after about a half-hour run using plenty of engine revs, the rattle disappeared.

Incidentally, using the correct oil is wise on any vehicle, but especially so where hydraulic tappets are concerned. I have known those who have used a thicker than recommended oil in a bid to cut oil consumption.

All they achieved was problems. Use only the correct grade.

Like most things these days, tyres are expensive and many of us are forced to buy used tyres from a breaker when renewal becomes necessary. Nothing wrong with that, but careful vetting is essential. Look not only at the treads for wear and damage, but thoroughly examine the inside of the tyre too. Another possible visit to the breaker was caused by a sinking clutch pedal. The owner said that the sinking occurred overnight and the following morning he simply pulled the pedal back up under pressure and the clutch was okay for the rest of the day.

He had been told that the fault was due to either the master cylinder (very expensive) or the slave, which was not quite so pricey – hence his thoughts about buying from a breaker.

CLAMP THE HOSE

It did seem like a master cylinder fault and I suggested clamping the flexible pipe overnight to find out if the pedal still sank. If it did, it would point to a defective master cylinder, but if it did not, then the slave cylinder was the likely culprit.

We had a Renault on which the brakes were working well, but if pressure was kept on the pedal it sank slowly to the floor. This happened more readily when the engine was running.

There was no loss of fluid and no swelling of hoses. All the brake cylinders were leak-free and apparently not sticking and in good condition. And so, with no leakage or swelling hoses, the master cylinder had to be the main suspect.

Clamps were fitted to all the flexible hoses and the pedal applied. It still went right down proving that the master cylinder was at fault.

If it had not, the clamps would have been released one at a time and the pedal applied. When one is released and the pedal sinks, this will show the problem area. - Star Motoring

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