Turntable stopped turning one day last week. Will turn slowly without glass plate on spindle, but not with any weight. Is there a schematic for turntable drive somewhere?

If the oven is STILL heating, but the carousel isn't turning, this problem is commonly attributed to a turntable motor that has worn out and may need to be replaced. The motor is attached to the center plastic piece (called a turntable shaft, turntable ring or coupler) under the middle of the glass tray. The following link explains how to access and replace the motor:

http://www.fixya.com/support/r3555716-replacing_a_turntable_motor_on_a_microwa

This is a very simple repair, that usually is not expensive. The price will be determined by the model and manufacturer. This repair can also be performed on an over the range model microwave oven WITHOUT uninstalling it.

You can refer to any of the following websites for comparison:

searspartsdirect.com
pcappliancerepair.com
appliancepartspros.com
repairclinic.com

The first three sites listed have helpful exploded view diagrams to assist you with locating and properly identifying the part(s) you may need.

The average price for a motor is about $25 to $45. If your model number is not listed at all the sites, use the part numbers from the Sears site and use them for your search criteria. The model numbers don't always cross reference, but the part numbers do. The part number for a replacement turn table motor for the model you have listed is WB26X10038 (listed as item 43). If your model number does not cross reference to all websites, use the part number from the Sears website as your search criteria.

NOTE: Even though the carousel may not be turning, you can still use the microwave while awaiting parts. You will need to physically rotate whatever you are heating about midway through the cook time to ensure even heating. Early model microwave ovens were not equipped with a rotating carousel and this was the common procedure.