Most automobiles use curved coolant hoses to transfer heat from the engine to a radiator. These hoses are specifically designed for each engine model, which have numerous clearances for hose paths. Replacing a tight-fitting hose that winds through a small engine can be time consuming, taking the average backyard mechanic about an hour.
Instructions
- 1
Drain the coolant from the system by turning the radiator petcock counterclockwise and allowing the coolant to drain into the drain pan. Without a petcock, the lower radiator hose must be removed to drain the coolant. Pinch the hose clamp with a pair of pliers, or turn the clamp screw counterclockwise and work it from the radiator nipple. With the clamp moved, the hose can be wiggled free of the radiator nipple and the coolant will rush out. Have the drain pan already in place. Release pressure by turning the radiator cap counterclockwise.
2Locate the opposite end of the lower radiator hose, buried into the engine and fastened to the water pump. The upper radiator hose is typically routed in a straightforward fashion, while the lower hose will worm through the belts and pulleys to reach the pump. Once the opposite end is located, note how the hose clamp is holding it to the pump. The angle of this clamp will usually determine the process of gaining tool access to release it.
3Most times, removing the radiator fan and fan shroud will help in working a tool into the area of the water pump. By unplugging the adapter that connects the fan to the wiring harness, the four corner bolts can be turned counterclockwise and the fan assembly can be taken out.
4Work the hose clamp from the water pump nipple, then twist the hose to free it. Over time, the hose has been heated and cooled to the point where it will bind to the water pump nipple, and take considerable force to break free. A common replacement procedure is to cut the hose at the nipple and remove it, then scrape off the encrusted hose remains from the pump. Once freed from the water pump, the hose can be backed out of the engine toward the lower radiator connection.
5Replace the hose with a new unit by working it back through the engine, following the path of the previous hose from the lower radiator nipple to the water pump opening. The bends placed into the hose are unique to each engine model, and usually only the proper hose will fit. Press the water pump end of the hose in place first, then secure the lower radiator connection, placing a hose clamp at each end. Tighten the hose clamps either by pinching the tabs or turning the clamp screw clockwise while the hose is covering the nipples on both ends.
6Refill the system with fresh coolant by tightening the petcock and pouring the coolant into the radiator cap opening.
