I have a coin-op washer model CA2742TQO that only fills 1/2 full on the rinse cycles, but fills full on the wash cycle. Any suggestions?

Get an operators manual and read if that is perhaps the "normal" operation of the machine !
You did not mention that what you notice is a sudden change of operation.

Try any of the following Sears links :

Sears on-line website (http://www.managemyhome.com/mmh/rails)

http://www.sears.com/Service (http://www.sears.com/shc/s/home_10153_12605)

http://www.searspartsdirect.com/partsdirecta (http://www.searspartsdirect.com/partsdirect/index.action?sid=PSHx20080114x00001I)

http://www.searspartsdirect.com/partsdirectb (http://www.searspartsdirect.com/partsdirect/index.action?sid=PSHx20080204x00001a)

Success!
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