On The Road To A Breakdown ??? ( part 4 of series)

Hear that hissing sound and see steam coming from under the hood????

It's probably a busted radiator hose...

There are several hoses on a cars engine and each one serves a different function.

The Upper Radiator Hose:

Which carrries coolant from the hot engine into the radiator to be cooled.

The Lower Radiator Hose:

Which carries cooled down coolant back into the engine via the water pump.

The By-Pass Hose:

Which carries coolant from the water pump into the thermastat for faster engine warm-up.

The Heater Hose:

Which carries warm coolant from the engine into the passenger compartment heater then back to the radiator

With today's smaller engine compartments and higer output engines.

Hose failure is caused by excessive heat, contaminants, and friction caused by parts rubbing against them.


There are several ways that you can check hoses. After the engine cools

Visual inspection:

Look at all your hoses and see if there are any cracks or swelling on the exterior of your hoses. also look for signs of coolant seepage around each hose connections.

Physical inspection:

squeeze each hose and se if it's brittle or spongy feeling. Also feel the clamps and see if they are loose.

Replacing A Hose...

Gates engineers recommend that all coolant hoses be checked when the system is being flushed and antifreeze replaced -- about every two years -- or whenever servicing of the radiator or water pump is required. Hoses showing obvious signs of wear, and those more than four years old, should be replaced immediately. Most EPDM hoses tend to bond to metals, so removal of coolant hoses from fittings must be handled carefully. It is important to avoid forcing or prying a hose to prevent damaging the fitting. Instead, use a sharp knife to cut off a hose .


Always check the spout to be sure it is not distorted or corroded. There should be no sharp edges, or burrs, which could damage the hose. Always clean the neck of the spout with a wire brush or emery cloth.

When installing a hose, dip the ends in coolant to lubricate it and slip clamps over each end. In cold weather (25¡F to 30¡F), the hose may be stiff. Warm the hose with hot water.

After slipping the clamps on the hose, push the hose onto the spouts, installing the engine end first. If the hose does not fit properly, remove it and reverse the ends. Whenever hose replacement is required, it's a good practice to also replace the clamps.

Finally, tighten the hose clamps, and refill the radiator to the recommended level. Also, check the vehicle's owners manual. Certain vehicles must have all the air bled from the system and have bleeder valves to do so, usually located on the thermostat housing.