Cars today are very reliable and generally built to a high standard. It was not always so and back in the dark days of the 20th Century it was not uncommon to see motorists stranded by the roadside, steam pouring from the under the car bonnet. Blown radiator hoses and thermostats were probably the reason. So, although things may be better today, it is still important to ensure that cooling system parts are checked regularly and replaced as necessary. Your local repair garage can advise.
Car Cooling Today
Today’s vehicles (classic cars excepted) now have sealed cooling systems. These are much more efficient and constructed with more durable materials. There’s better science behind the antifreeze and coolant mixtures in the system, far superior for preventing an engine from overheating. Modern design produces better cooling air flow and consumables like hoses will last much longer thankfully, especially if the vehicle is annually serviced at your local car servicing garage.
That’s not to say though that overheating is out of the question and it is often in summer when faults will be found out, for obvious reasons. There won’t be the flow of cold air through the radiator that we get in the winter, for example. The air will already be warm (we hope). If a car does overheat then these days many drivers would be at a loss as to know what to do. Further, in these technical times, the problem can sometimes be more complex than a simple thermostat. Here’s what to do:
Check The Coolant Every Week
Note: Always let the engine cool down before investigating.
Overheating could be due to a loss of coolant, a damaged radiator caused by rubbish from the road, a faulty radiator fan, a split hose or even a blown head gasket.
When the engine is cold, the coolant level in the expansion tank (see the handbook) should always be on the marked level. Systems are sealed so this should never change unless of course the car is losing fluid. The expansion tank is the first port of call. Make this a weekly job. It doesn’t take a minute.
Check The Rest Of The System Too
Search for any tell-tale splits or water damage on hoses and, where possible on complex modern cars, the radiator. If the engine head gasket has blown, the tell-tale sign is revealed by removing the oil cap on the top of the engine and looking at the oil. If there’s a milky sludge, the problem might lie there, so call the garage immediately.
Keep An Eye On The Dashboard
Dashboard warning lights are there for obvious reasons. If there is an issue with the cooling system and the car is overheating, the warning light should illuminate. Usually the pictogram is of a thermometer. Stop as soon as it is safe to do so. Trying to carry on will make a dodgy situation worse and the result could be seized engine and a rueful look from the garage proprietor when passing over a substantial invoice.
Turn On The Heater & Check The Fan
If the warning light illuminates, turn off any air-conditioning and turn the heater onto maximum. This won’t in any way solve the problem but it will help to draw heat off the engine while you find a safe place to stop at. Open the windows; it’s going to get hot. Upon stopping, open the bonnet – don’t touch anything – and with the engine running watch the fan to see if it is working. If the engine is hot, the fan should be switching on and off. If it isn’t, well, that may well be the issue.
What Next?
What you do not do is continue driving. The results of continued overheating can and will be catastrophic for the engine. Unless you understand complex modern engines the likelihood is that the car is garage bound where a diagnostic check can be made.
Modern vehicles are much more reliable and you would have to be unlucky to experience overheating problems on a properly serviced car. Keep up the weekly checks of the system. The vehicle’s handbook will have the details. It’s much better than standing at the roadside waiting for help.