How do I replace the Coupler?

You’ll need: allen wrench, possibly a // socket driver and maybe a hammer

Make sure the motor is unplugged

Instructions for all upright model glass washers with motor mounted above water.  Note: There is no Coupler on submersible glass washers.

Make sure the motor is unplugged!  Once the motor is determined to be bad you can still use the unit in your sink as a manual brush cleaner until the new motor arrives.

The set screws around the bottom of the motor where it meets the stand pipe need to be removed using a XX allen or xx open end wrench.  Once this is done you can remove the motor from the stand pipe.  If the motor is difficult to remove you can coax it by using a hammer on the underside of the motor hitting it gently along the bottom edge to loosen it.

Pic of coupler assembly

Once the motor is removed, using an xx allen wrench loosen the allen screw on the Coupler and remove the Drive Shaft from the Coupler.  Inspect the Drive Shaft at this time for rough or uneven teeth.  Consider a new Drive Shaft at this time.  Note where the old coupler is located on the motor drive shaft.   Remove the old Coupler from the motor by loosening the allen screw and lifting or prying the Coupler off the motor shaft.  The new Coupler should be placed on the motor shaft at the same level the old coupler was.  Using the blade of a butter knife as the gap should be about right.  Hand tighten.  Slip the gear Shaft into the Coupler and hand tighten.

Pic of shaft through bottom bushing

Replace the motor by slipping the Shaft down the stand pipe and through the Bearings.  Slip bottom collar of motor over stand pipe and push down on motor until completely seated.  Turn the machine on its side and check to see how far the shaft protrudes through the bearing.  It should be completely through but by no more then 1/8 inch.  If you need to adjust the shaft, remove the motor and adjust the coupler position on the motor shaft appropriately.  Return motor on washer as described and hand tighten 3 set screws.    Plug into a ground fault receptacle and clean, clean, clean!

Cause or how do I avoid this problem from repeating?

Using a quality recommended low foam bar glass cleaner is the most effective way to avoid wear and get the best results.  Using the wrong brushes for your glassware, pushing down hard on the brushes and washing pictures on the washer is detrimental to your machine and will cause premature wear.