Gretchen, I believe that the number 2142 is the motor number. The plate that is on the bottom front of the machine (tipping the head back slightly) should be where the model number is. It will probably be something like 158.1752 or maybe 158.95. It should also have a serial number. Kenmore manuals will sometimes cover more than one model. Did the pictures in the manual look very similar to the machine you have?
Janey - Neat people never make the exciting discoveries I do.