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Radiator and Heater Hose Replacement

Change your hoses without getting hosed

Unless you're driving an old rear-wheel-drive Volkswagen Beetle or lucky enough to be carving up the pavement in a pre-'98 Porsche 911, the engine underneath the hood of your car keeps from overheating by way of a liquid cooling system. Each time your engine starts, the process of internal combustion begins. Gasoline, diesel, or whichever fuel burning up inside the cylinders, begins to create heat. This heat must be channeled away from the engine, lest the pistons and engine block turn into a solid lump of molten metal.

Way Coolant

Surrounding the cylinders in which the pistons and valves do their internal combustion fire-eating act is a jacket that contains engine coolant. Heat from the combustion going on inside the cylinders is transferred to this coolant. The coolant is circulated by way of a water pump. The coolant travels through a series of channels on its way out of the engine, and through a rubber composite hose into the radiator. The radiator allows heat to pass from the coolant into the surrounding air and, presto, the coolant returns back from where it started through another hose and cooler than it was when it came out of the engine. In this way your engine keeps its cool.

In a brilliant stroke of engineering, the automobile heating system utilizes a smaller radiator of sorts called a heater core. Smaller rubber hoses bring hot coolant to the heater core. This miniature radiator along with a blower fan keeps your toes toasty in winter. So it goes.

Old Faithful

This cold and hot act takes its toll on engine coolant. Heat unleashed by the radiator and engine itself especially beats up the radiator and heater hoses. Inspecting and replacing the radiator and heater hoses once a year is easy. It's not only simple, it can prevent spending that summer afternoon picnic on the side of the road waiting for a tow, instead of down by the lake enjoying yourself.

The obvious sign of impending hose failure is coolant seeping from the hose itself—a miniature version of Yellowstone's Old Faithful geyser steaming out from a hose fissure is a dramatic manifestation of hose expiration. The radiator hose that looks like a snake that swallowed an egg will soon blow, usually on your way to a job interview or to pick up a pal from the airport. Less obvious signs of decay can be seen and felt by latching hold of a cold radiator or heater hose and giving it a good squeeze. Never grab onto a hot radiator hose or attempt to remove a radiator cap from a hot radiator. Hose material cracking, or a spongy or sticky feel are bad signs. Since most sane automobile engineers place the radiator up at the front of the vehicle for the best possible heat transfer and engine cooling, replacing the radiator hoses is usually a basic job. Heater hoses, being smaller in size and trickier in routing, can present more difficulty.

Service Time

The best time to inspect your heater and radiator hoses is during coolant service, since the first step to removing the hoses is draining the system of coolant. A little preventative cooling system maintenance can stop problems before they start.