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.sears.com/Service

http://www.searspartsdirect.com/partsdirecta

http://www.searspartsdirect.com/partsdirectb

Success!
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