How to Replace Cooling System Heater Core Hoses

The heater hose delivers the engine's coolant into the heater core. A blower motor blows air through the heater core to deliver heat into the automobile's interior. Symptoms that indicate you need to replace the heater hose are an engine gauge temperature reading that is higher than normal, the car's heater doesn't pump out heat or it leaks coolant. Follow a few steps to replace the heater hose.

Instructions

Precaution and Preparation

1

Check the level of coolant to determine that you have adequate antifreeze. Make sure that the car's engine and radiator are cool before you remove the radiator cap.

2

Make sure the radiator cap's rubber ring is in good condition. Squeeze the cooling hose to make sure it is still soft and pliable, and check for dry rot, cracks or weaknesses.

3

Place a drain pan or bucket under the radiator to catch the poisonous coolant. Safely discard the coolant if it is unusable and clean up any spills.

The Process

4

Drain the coolant by pushing down and slowly turning the coolant pressure cap to release the pressure. Open the drain valve on the bottom of the radiator.

5

Remove anything that is in the way when you replace the coolant system heater hose. This includes clamps, screws, other hoses, air intake boot, metal bracket mounting point and electrical connectors.

6

Take notice of where all of the parts are located so you can put them back in the correct place, and draw a diagram if necessary. Place screws and clamps in a safe place so they aren't lost.

7

Release the clamps on both ends of the heater hose with pliers or a screwdriver. Carefully work the hose loose from the fitting so you don't cause damage to adjacent parts.

8

Scrape off the old sealer and apply new sealer on the fitting when you replace the heater hose.

9

Slip the clamps on the new heater hose; make certain the hose ends are over the fittings. Check for correct placement of the clamps and secure them tightly.

10

Close the valve on the bottom of the radiator, pour coolant back in it and replace the cap. Check the gauge to make sure the liquid is at the full line, and start the engine to check for leaks.