If the fan motor is running loud the fan motor can be lubricated by removing the
four screws holding the circuit board in place. (On later desirnged smoke unit
designs the housing is split and only the two screws next to the fan motor need to
be removed to expose the fan impeller).

Remove the board and you will see the fan impeller (it is black). The impeller is
held on by a friction fitting, it just pulls off. After you pull the impeller off you will
see the motor shaft.

Put a few drops of household oil on the shaft. Run the smoke unit being careful
not to touch the heaters or short the top board to ground. The noise should quiet
down.

Then, remove the remaining lubricant with a paper towel. Make sure the impeller
doesn’t hit the bottom of the housing and that it turns freely.
If the fan motor still isn’t operating quietly, replace the fan motor. Remove the
impeller and find two tiny Phillips head screws. When you remove them the fan
motor will drop out.

NOTE: Install wires to smoke unit motor as before to ensure proper impeller
rotation. Also, remember the fan motor uses DC, a battery (8.4 v NiCd) will
operate the motor for testing.