How to Replace the Motor to Base Wiring on an Old Fan (Dave Friedlund)

The most common restoration question on old fans is how to replace the wiring.. The line cord is fairly straight forward, but the wiring from the motor to the base is more difficult. Here's how I do it:

Step 1: Identify the Connections

Disconnect the wiring from the motor at the speed control in the base of the fan. There are typically 2-3 wires (most of the time 3). Mark each of the three wires. I like to use Liquid White Out. Make dots on the wire and a corresponding number of dots on the point where it's connected to the speed control. (ie 1-dot, 2-dots, 3-dots) Remove the wiring at the speed control. It's also wise to make a make a little chart and measure the resistance with an ohm-meter for every combination of the three wires. (this can save time during re-assembly)


1-2: ____ ohms

1-3: ____ ohms

2-3: ____ ohms

Step 2: Prepare for Removal of the Stator

The Next step is to remove the stator from the motor case.

1. Remove the motor from the fan. Make a diagram if needed for re-assembly.

  1. Remove all nuts and remove the motor cover. (usually from the back) If it's tight try and give the front of the rotor a tap with a wood or brass mallet and it will usually pop the cover off.

  2. Remove the rotor

  3. Remove the threaded studs that go thru the stator. I usually use needle nose vise grips and grab a portion of the stud past there a nut will go since the vise grips can damage the stud.

Step 3: Remove the Stator -Cast Iron Motor Case

For a cast iron motor case place a short piece of iron pipe inside the motor case (2-3" diameter) and gently tap it on a concrete or steel surface. The mass of the stator will usually break away from the case easily. A few taps and its usually out. If it's real stubborn try the freeze and heat/liquid wrench trick in 3A. Be extra careful if you have a Century skeletal or GE Pancake with an open frame motor.

Step 3A: Remove the Stator - Stamped Steel/Press Fit Motor Case

These stamped steel case stators can be a challenge (ie Westinghouse):

1. Remove the back cover of motor and completely remove stator housing studs.
2. Open a vise to precisely the ID of the motor case + a few thousands of an inch more.
3. Place edges of motor housing on top of vise jaws.
4. Get 4 long machine screws (10-32 I believe). (length > thickness of motor case) Screw them thru the housing into the stator. Make sure you get good thread contact into the stator.
5. Align two of them right over the vise jaws.
6. Use a hammer and tap the screws alternating between them. Rotate the stator 90 degrees and repeat. The stator should gradually come out thru the open vise. Go slow and don't let the stator get cockide as it comes out.

If this doesn't work and all else fails you can drill two small holes in the front of the motor case and use a pin punch to help motivate the stator to come out. The holes won't be too noticeable and it's a small price to pay to save a fan.

Before I proceed with this I would freeze the motor and then go around the housing with a propane torch to try and break the rust/corrosion hold. A little liquid wrench around the circumference might also help but go easy.

Note: For step #4 it might help to start with short machine screws which are less likely to bend and then switch to longer ones once the stator is coming out.

Step 4: Replace the Stator Leads

  1. Remove what's left of the old wiring from the stator. Once again make a diagram of where each wire goes. Be very careful as the wiring can be brittle and break the tiny lead from the stator. Get to where you have the 2-3 small magnet wire leads.

  2. Since you've already gone to this much trouble use good quality replacement cloth covered wire. (I recommend Olde Time Radio as a source) Clean with magnet wire leads down to bare copper and solder on the new leads. I use 2-3 small pieces of increasingly larger diameter shrink wrap tubing to cover and insulate the connection. (one covering is not enough and I avoid using electricians tape). Sometime you will need to use a small jumper magnet wire as am intermediate connection to the new lead.

  3. Make sure you have a strong mechanical connection to the stator. Wax ribbon string, dental floss, tie wrap, epoxy can all be used to insure you aren't stressing the delicate connection. Make sure your splices end up where there is clearance once the stator is back in the case.

  4. I always spray stators with epoxy insulating spray paint. It soaks into the old windings and re-insulates the old wiring. Mask off your new lead wires and the outer portion of the stator.

Step 5: Re-install the Stator

  1. Before you start re-installing the stator I like to very lightly grind the outer area to remove the old rust and to make it reinstall easily. (it has to be a tight fit though) I also like to put a very thin film of oil of vasoline on the outer area prior to fiting it back in.

  2. The best method is to press the stator as far in as you can by hand and then use the threaded studs and nuts to pull it all the way into the case. Some have suggested freezing the stator and warming the case prior to doing this. I also like to rethread the studs and cap nuts to clean them up prior to re-assembly.

  3. Measure the resistance per the table in Step #1 and reconnect to the speed control .