My heater motor squeals
Posted: Jan 31, 2006 9:39 AM
PROBLEM My heater blower squeals, or does not work some of the time.
Solution Heater blower motor needs cleaning, lubrication, or replacement.
How do I know? Sluggish heat, noisy fan on highest or all settings, no fan, eventually smoke in the cabin from burnt blower motor.
Fix: Pull the blower motor and replace it with a new unit. Sometimes, cleaning the old motor and contacts with electric parts cleaner and lubing the shafts and bearing points can buy you some time. Pulling the motor is not difficult and takes about 1/2 hour from start to finish. Disconnect battery if safety is your thing. Remove the hood seal, and the mounting screws for the firewall cover. Cut zip ties to the wiring harness and move wiring out of the way. You should be able to access the blower housing at this point. Work with the plastic fan covers until you can remove one or both--they're(usually) flexible so pull them outta there. Unsnap the retainer for the motor, disconnect the leads and pull the assembly out--watch your knuckles. Flush the motor with electric parts cleaner and lubricate the bearings with machine or turbine oil* (McMaster-Carr P/N 1244K14) if you want to try to use the old blower. Assy. is reverse of removal.
*Do not use PTFE-containing lubricants such as Tri-Flow, as the PTFE will clog the sintered bearings.
Solution Heater blower motor needs cleaning, lubrication, or replacement.
How do I know? Sluggish heat, noisy fan on highest or all settings, no fan, eventually smoke in the cabin from burnt blower motor.
Fix: Pull the blower motor and replace it with a new unit. Sometimes, cleaning the old motor and contacts with electric parts cleaner and lubing the shafts and bearing points can buy you some time. Pulling the motor is not difficult and takes about 1/2 hour from start to finish. Disconnect battery if safety is your thing. Remove the hood seal, and the mounting screws for the firewall cover. Cut zip ties to the wiring harness and move wiring out of the way. You should be able to access the blower housing at this point. Work with the plastic fan covers until you can remove one or both--they're(usually) flexible so pull them outta there. Unsnap the retainer for the motor, disconnect the leads and pull the assembly out--watch your knuckles. Flush the motor with electric parts cleaner and lubricate the bearings with machine or turbine oil* (McMaster-Carr P/N 1244K14) if you want to try to use the old blower. Assy. is reverse of removal.
*Do not use PTFE-containing lubricants such as Tri-Flow, as the PTFE will clog the sintered bearings.