OEM 2003 Buick Century Heater Core

2003 Buick Century Parts Questions & Experts Answers

• Q: How to replace the Heater Core on 2003 Buick Century?

  A: The first requirement for heater core replacement tasks involves getting the Hose Clamp Pliers (J 38185). You must begin with removing the fuel injector sight shield from 3.8L engines and draining the coolant first. The Hose Clamp Pliers (J 38185) should be used to move the heater hose inlet and outlet clamps off the heater core before disconnecting both hoses. The removal procedure begins with taking out the vacuum tank together with the floor carpet and rear floor air outlet duct through the floor reinforcement holes. Disconnect the heater core outlet cover and vacuum harness bracket by removing each respective bolt. Remove the bolts from the vacuum harness bracket and place it aside before you remove the screws from the heater core outlet cover by positioning the cover towards the floor and the rear for disconnection from the rear area floor duct assembly. Begin by opening the heater core outlet cover then extract all screws from the heater core cover before discarding both seals (1,2) found within the heater core cover and caulk from the heater core cover. First remove the outer seal from the heater core before taking out the screw from the heater core support bracket along with the heater core support bracket itself. Remove the screw from the heater core pipe retainer clamp before extracting the heater core from the HVAC lower case along with the heater core pipe retainer clamp from the heater core pipes. The HVAC lower case requires seal removal of its lower seal together with center seal and upper seal and side seals. Start by positioning the side seals followed by the upper seal and center seal and lower seal on top of the HVAC case. Afterward install the heater core pipe retainer clamp to its respective heater core pipes and place the heater core onto the HVAC lower case. Follow the installation of screw to secure the heater core retainer clamp with 1.5 N.m (13 lb in) torque before installing screw to the heater core support bracket where torque should remain at 1.5 N.m (13 lb in). The next step requires you to install the outer seal to the heater core followed by new seals and to the heater core cover. Then apply caulk to the heater core cover before installing screws that must be tightened to 1.5 N.m (13 lb in). Secure all heater core outlet cover screws with 1.5 N.m (13 lb in) torque then install the HVAC vacuum harness bracket with its screws tightened to 10 N.m (89 lb in). After connecting the heater core outlet cover with the rear floor air outlet duct you must install the duct through the holes in floor reinforcement before laying floor carpet and vacuum tank. To complete the installation thread heater core inlet and outlet hoses and clamp them with Hose Clamp Pliers (J 38185) while reinstalling the fuel injector sight shield when working on a 3.8L engine and filling coolant.