Sometimes the heater hoses on a car are two different diameters. The size is determined by the inside diameter (ID) of the hose. Hose comes in long rolls. Be sure that you select the correct size hose before cutting it off the main hose roll.
Twist the old heater hose to loosen it, and cut it carefully with a sharp knife if it does not remove easily. When installing the new section of hose, check the following:
- Be certain that the hose does not interfere with manifolds, belts or spark plug wiring.
- Check to see that the hose will not be damaged by movement of the engine or accessories.
Position the screw side of the clamp for easy access. On lower radiator hoses, an extra long screwdriver can be used from the top of the engine compartment. Be sure to screw the hose clamp is positioned so it cannot accidentally come into contact with the cooling fan.