Car Maintenance Guide
Hoses

Hoses are used on many components of every vehicle. They carry liquids (fuel, coolant, transmission fluid) and gases (for air conditioning). Hoses also set in motion vacuum-operated components (such as cruise control systems and power brake boosters) by transferring vacuum from the engine.

Hose Inspection

Cold Engine Inspection

• Check for small leaks before you start your car, while your engine is still cold. Small leaks can be temporarily slowed by wrapping duct tape around the hose. This temporary patch should only be used in an emergency situation. If your vehicle is driven when it is low on coolant, serious engine damage may occur. Replace the hose as soon as possible.
• Firmly squeeze the radiator and heater hoses. A hose that feels very hard or makes a "crunch" as it is squeezed is deteriorating and should be replaced. You also should replace hoses that are extremely soft, sticky or oil-soaked, as they are likely to fail.

• After driving the car long enough for the engine to be fully warmed up, turn off the engine and immediately open the hood. Make sure the upper radiator hose is not collapsed. If it is, it may indicate a problem and should be checked by a qualified technician.
• Look carefully at all the hoses to spot any swollen areas. Such areas indicate weak spots.
• Inspect around hose ends for dampness, deposits or buildup of dried coolant. These could indicate that a "cold leak" is present. A cold leak is usually a very minor leak that occurs after the vehicle has cooled down, and expansion and contraction of components has occurred. All coolant leaks should be addressed as soon as you notice them. Over time, these leaks will get worse and could lead to an expensive repair. An inexpensive gasket or a simple tightening of a hose clamp may be all that is needed to avoid an expensive repair.

Visual Signs of Wear

• Cracking: Cracking is caused by heat and age.
• Bulging: Bulging is caused by high heat or oil or grease exposure.
• Soft: Oil or grease exposure can cause hoses to become soft.