We have a MHW2000AWW Neptune washing machine. It is starting to have the same problem that we experienced over a year ago. The washing machine goes through a complete washing cycle but does not perform the spin cycle so that the clothes are totally soaked at the completion. We can manually rotate the control knob around to the extra extract spin cycle point and start the machine. It will complete the spin cycle. At the end of this manually started spin cycle the clothes are damp as expected and there is water sitting in the flexible seal by the door next to the drain. What can we do to correct the problem of not doing the spin cycle as part of the normal washing cycle and leaving excess water in the flexible cylinder seal near the door without having to replace the motor and control board again which we did in April 2010?

This is probably simply a problem with your empty pump filter being clogged. The empty cycle is timed and if it can't get all the water out in time because the filter is blocked and slowing the empty down, then it will fail safe and won't step on to the final spin cycle with excess water in the drum. Your repeat of the rinse/spin cycle is giving it extra empty time and then the spin works OK.
You need to locate and clean the filter. Depending on the model (not sure which with the model you mention) there is either a round filter cap on the front of the machine at the bottom (It may be behind a small door or hidden behind a clip on panel on the bottom) Many models of this design also have a small hose to the right of the filter cap that you can pull out, remove a plug from and drain off any water in the filter before you remove the filter and get your floor wet, so take a look for this before you remove the filter and get soaked.

OR

You will need to access the debris trap from the back of the machine. If there is no filter at the front, pull the machine out and you will see a roughly oval panel at the bottom of the rear of the machine. Unscrew the 3 or 4 screws and unclip. Directly below the drum, you will now see a rubber "Cup" like bulge in the black pipe, with a plastic tube connected to a plastic pipe. The cup is held in place by a large jubilee clip. Unscrew the clip, pull off the rubber boot to expose the debris trap (A conical plastic cage with a ping pong ball in it) Take out the ball and the plastic trap, clean out the debris and replace the trap and the ball (Note that the cage may have a slot in it that locates in the rubber boot, make sure it lines up, or it won't reassemble correctly). Now push the boot back onto the fitting at the bottom of the drum where it came from and tighten up the jubilee clip, making sure that it is fitted correctly (it too may have a small slot out of it that fits around a protrusion on the bottom of the housing).