Hot, hot, hot!
There’s that one look that every classic car driver recognises in the height of summer. You’re stuck in a traffic jam, the sun is beating down on the bodywork, and as the sweat slowly trickles down your back, your eyes are drawn – as if by a magnet – to the temperature gauge. And lo and behold – the needle is sweating too. Slowly but surely, it creeps to the right, and suddenly you get the feeling that your own heart is doing the same. Welcome to the most wonderful – and at the same time, the most sweat-inducing – time of the classic car year.
Here at the Grand Tour Society, we know what we’re talking about. On our last rally, with temperatures that our classic cars took more as a personal insult than as ideal driving conditions, we had ample opportunity to study the relationship between old metal and intense heat. And as we all know, a problem shared is a problem halved, so here’s a little survival guide for anyone whose beloved car still manages without automatic climate control and an on-board computer.
The classic summer problem is the engine overheating in a traffic jam. As long as you’re driving, the airflow keeps the engine cool, but when you’re stationary, the mechanical fan barely turns, and the heat builds up under the bonnet. Here’s a trick that’s as old as it is ingenious – and one that does credit to the driver’s resourcefulness: turn the heating right up. Yes, you read that correctly. The heating draws heat from the engine into the cabin, thereby taking the strain off the radiator. For the passengers, it’s a sauna on wheels; for the engine, it’s a lifesaver. So anyone stuck in a traffic jam at thirty-five degrees, with a bright red engine light and the heating cranked right up, isn’t a madman – but a connoisseur.
The second major summer issue concerns, above all, fans of carburettor engines: the formation of vapour bubbles, known in technical jargon as ‘vapour lock’. In very hot weather, the fuel can evaporate whilst still in the fuel line, before it even reaches the carburettor. The result is frustrating and never fails to baffle: the car is running perfectly, you pop into the bakery, come back with some bread rolls – and suddenly the engine starts spluttering and simply refuses to start. A few minutes’ patience, until everything has settled down again, is usually the best remedy. Drivers of modern fuel-injected cars are no longer familiar with this phenomenon and look at you as if you were talking about a steam locomotive when you explain it. That’s precisely what gives it its charm.
To prevent this from happening in the first place, it’s worth taking a close look at the cooling system – ideally well before the first heatwave. A limescale-clogged radiator no longer cools properly, a worn-out thermostat opens too late, and a worn-out V-belt causes the water pump to slip. The coolant mixture ratio must also be correct, as the coolant not only lowers the freezing point in winter but also raises the boiling point in summer. Taking precautions here will save you from having to call out the breakdown service at the hottest spot on the most scenic mountain pass.
And then there’s all the stuff you don’t even think about at first. The oil temperature rises faster than you’d like in hot weather and under heavy load. Tyres that have seen better days really don’t like the scorching tarmac and should be checked regularly for age and fine cracks, as a good tread depth alone says nothing about hard, brittle rubber. And finally, the most important factor of all: the person behind the wheel, who is mercilessly cooked in a cabin without air conditioning.
So, to round off, here are a few simple tips that have proven their worth time and time again. Setting off early in the morning, when the air is still cool and the roads are still empty, is worth its weight in gold in the height of summer. Always carry enough water – for people to drink and, in an emergency, for the engine too. And if the temperature gauge does happen to climb into the red zone: pull over, let the engine cool down and under no circumstances open the hot bonnet. The boiling liquid is under pressure and will find its way out with a determination you wouldn’t wish on anyone.
At the end of the day, the heat is as much a part of summer as the rattling of an old engine. It turns a leisurely ride into a mini-expedition, every destination reached into a small triumph, and us riders into a close-knit community of slightly mad people who choose to sweat. And the next time the temperature gauge starts to sweat along with you, you’ll know what to do: turn the heating on, keep calm, and don’t eat your bread rolls until you’ve cooled down.