Rebuilding a Westinghouse WC Vend Motor

[tkaz]

I decided to take a look at the vend motor on my new Westinghouse WC-78-MD, as it seemed like it was struggling a little bit to vend the bottles.  I took some photos of the disassembly for future reference for the folks here.

To remove the motor:
1. Pull the C-clip holding the vend mechanism, then move it up out of the way (red arrow in 1st photo)
2. Remove the two index switch bolts (yellow arrow).  There is a metal strip behind them that they screw into, remove that.
3. Remove the 5/16" bolt (green arrow)
4. Remove the two 3/8" bolts (blue arrow)
5. The assembly will now pull out, I didn't remove the wires as I felt that would have complicated things more.  Have a box or something you can work on the motor with sitting in front of the machine

To remove the motor from the gear assembly:
1. Pull two small screws from aluminum cover on the back of the motor.  Carefully pull the cover off the motor while pushing the wiring through the grommet (sorry, no photos)
2. Remove the four screws from the back of the motor (red arrows, second photo) Leave the bottom screws in so the rotor stays in place.
3. The motor assembly now pulls straight back from the gear box (third photo)

[tkaz]

Disassembling the gear box:
1. Pull the C-clip from the front of the motor shaft and remove the rotating assembly
2. Remove the two 3/8" bolts from the bracket
3. Mark reference points with a sharpie on the support metal, then remove the two 5/16" bolts
4. Make a reference line on the side of the gear box assembly, going from front cover to back, this will assist greatly in reassembly
5. Remove the three screws from the back of the gear box (red arrows, third photo)
6. Hold the assembly with the front up and the back down (otherwise the gears will fall out), and pull apart the assembly sections
7. Note the positions of the gears, all three are unique and will only go back into place one way

[tkaz]

Cleaning the gears:
1. Pull the gears out and label them for reassembly.  Give each gear a good cleaning, I use automotive brake cleaner and a nylon brush.  Inspect the gears for wear on the teeth, I found a couple of chipped teeth on the second one, requiring shims to miss the bad spots later.
2. Clean the flat surfaces of the gears with a red scotch brite pad or sandpaper.  I found rust buildup on a couple surfaces and removed it before it caused more problems.
3. Clean the insides of the gear casing with the same methods.

Reassembly:
1. Lubricate all moving pieces with silicone lube or another medium weigh grease.  Motor oil is too light and automotive bearing grease is too thick, avoid those.
2. Place each gear back on its respective stud, ensure that the four gears rotate freely
3. Place front cover back onto the back, using the reference line made earlier to align the two
4. The rest of installation is the reverse of the first two sections, replace bolts and test out the motor.

[collecture]

Does your motor have a model number?
That is a different make than most Westy S-O-M motors I've come across. Merkle-Korff made the ones I have seen in the machines and can't open them up.
Thanks for taking the time to post details!

[tkaz]

Here's a close look at the label on the gear assembly, I don't think there was any ID on the motor, but I can check for that tomorrow.