Chevrolet pickup trucks utilize an electric heaterfan to push hot air into the cab. Hot engine coolant leaves the engine andflows through a heater hose to the heater core, a small copper brass oraluminum radiator mounted in the vehicle's firewall. The heater fan blows airducted either from the passenger compartment or outside the vehicle
, over theheater core's fins, drawing heat off the core. Electric or vacuum-controlleddoors in the interior heating system's ducting controls whether the hot air isblown at the floor, dashboard vents or against the windshield.
? On a Chevy pickup, the heater fan is locatedalong the firewall inside the passenger side fender. Stand in front of thevehicle and look at the air-conditioning condenser mounted on the engine.Follow the hoses that lead back toward the air-conditioning coil. The hoseswill connect to a large fiberglass box bolted to the firewall---this is theheater case. If your vehicle was not originally equipped with air conditioning,follow the heater hoses back to the fiberglass box. The heater fan will bemounted on the left side of the heater case (your left not the vehicle's) justbehind the fender well. Removal
Beginby disconnecting the ground cable from the negative battery terminal. Loosenthe bolt on the clamp and pull the ground cable off the negative batteryterminal. Locate the heater fan and disconnect the positive and negativeelectrical leads. Take notice of which terminal on the electrical motor theblack wire is connected to. Black wiring in automotive applications representnegative or ground. The wires must be installed on the new motor in the sameposition as they were on the old. They will be attached with plastic connectorsthat can simply be pulled off the contacts. The heater fan is bolted to the heatercase with three or four hex head screws. Remove these screws and pull theelectric motor straight out. With the motor removed, you will be able to seethe plastic fan blades mounted on the back side of the motor. Remove theretaining nut that connects the fan blades to the electric motor and pull theblades off. Installation
? Installation is the reverse of removal. Beginby reattaching the fan blade to the electric motor and reinstalling theretaining nut. Then slide the heater fan assembly back into position in theheater case. Reinstall the three to four hex head screws that secure the case.Then reconnect the positive and negative electrical leads, making sure toconnect the black wire to the negative terminal. Finally, reconnect the groundcable to the negative battery terminal.
Read more: Replacing a Chevy Pickup Heater Fan ' eHow.com