Your schematic is a little hard to look at for old eyes. Look at the schematics in the below discussion to see if you have something close to these. You can do like I did and modify these using MS paint. You might also do a board search for 4051 to see if there is a link to the schematic you used. If two of the three 4051 chips work, then the wiring or operating logic for the third ship probably needs to be looked at closely.
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1227132571/22