Car Care: Keeping cool on the road

Jack Biddle
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If you own a vehicle with a heavy workload, it’s worth spending money to keep the cooling system in good order.

If you own a vehicle with a heavy workload, it’s worth spending money to keep the cooling system in good order.

Cooling systems need attention

Walking into a rented house that had been closed up for several days revealed wet floorboards, saturated carpets and the hissing sound of leaking water. The cause of the problem was quickly traced to a split in the main water pressure hose connection feeding the home’s hot-water cylinder.

Thank goodness for tradies who make themselves available 24/7 to handle such emergencies.

Long story short, the plumber was able to carry out a patch-up to get the occupants through the weekend. The long-lasting fix and recommendation involved the removal of skirtings and gib board, plus a scramble under the house to check the condition of the plastic pipe and a thorough inspection of any other connections.

It’s a similar but different scenario with the way cooling systems operate in motor vehicles. Replacing only one faulty hose, for example, can be a very temporary repair indeed. It can sometimes lead to severe engine overheating a short time later.

When one cooling system hose shows signs of leaking or fatigue, you can almost guarantee there will be others in a similar condition.
Repairing one obvious leak only places increased pressure on the next weakest link in the cooling system chain. If the hoses were fitted at the same time, in theory, they should deteriorate at roughly the same rate.

So if you get the call from your repairer that one hose is past its use-by date but they want to replace a couple of others to be safe, it’s hard to disagree.

The danger is these sorts of jobs can snowball out of control very easily, especially the older a vehicle gets. There is often a fine line between removing the thermostat, giving the entire cooling system a clean and flush or simply draining the radiator, doing the obvious repairs, adding some inhibitor, pressure-testing the system to check for obvious problems, closing the bonnet and leaving well enough alone.

The old bangers that are almost on their last warning with owners are at the highest risk of problems after their cooling systems have been given a big flush and new inhibitor added.

Leaks can start to develop in heater cores, radiators, frost plugs and head gaskets because the sludge has kept leaks at bay.

At the end of the day, it comes down to the trust you place in your repairer and the workload on the vehicle. The holiday season is renowned for cooling system issues, because the trusty old family car is suddenly expected to carry extra loads or even tow for long periods in high temperatures.

Flushing of cooling systems can also become an easy on-sell for some repairers.

From new, most cooling systems these days don’t require flushing for up to 200,000km — or 10 years in some cases — and provided the correct additives are used, hoses certainly don’t deteriorate like they used to.

If you own a vehicle that is expected to undertake a high workload, it’s worth spending the money to keep the cooling system in good order.

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