Bench Preparing Heater Blower Motors

You might not think that there is much to do to prepare a blower motor for install.

We recommend running a new blower motor on the bench for up to 5 minutes prior to installation. This is done to reduce the amount of brush material that is blown on to the evaporator in the first few minutes of operation. As the motor starts life it has a round commutator that a square brush rides on. This causes the brush to have quick wear as it first begins to ride on the commutator and wears to match its’ round shape. Once the brush has worn to match the commutator the wear reduces due to the additional surface area on the commutator and therefore less brush material is blown down wind. The reason this is worth considering is that the brush material can be corrosive to certain types of metals, like the metals in heater cores and air conditioning evaporators. Take a few minutes before install to ‘prep’ your blower motor and help your evaporator to last as long as it can.