DURING TAXI OUT CHECK; A CRJ-200 FLIGHT CREW NOTICED RUDDER DID NOT GO FULL LEFT AS INDICATED ON EICAS SCREEN. ITEM DEFERRED; ACFT DEPARTED. ACFT LATER FERRIED BACK TO BASE DUE TO RUDDER CONCERNS.

Narrative

ACFT WAS IN REMOTE AREA VERY CLOSE TO TXWY AND EMER EQUIP IN AREA FOR ANOTHER ACFT. FLT WAS PUSHED BACK FROM GATE AND TAXI CHK BY FLT CREW REVEALED RUDDER INDICATION DID NOT GO FULL L. UPON BOARDING ACFT; I VISUALLY SAW THE INDICATION ON EICAS SCREEN. APPEARED TO BE 'DCU 1 ISSUE.' R&R'ED DCU 1; DID NOT CHANGE INDICATION. REINSTALLED ORIGINAL DCU; INDICATION DID NOT CHANGE. MAINT CTLR SAID ITEM WAS DEFERRABLE PER MEL; SO WE BEGAN WITH THE DEFERRAL. FROM THE GND WITH THE RUDDER L; THE INSPECTION STRIPE APPEARED VISIBLE; NOT KNOWING WHETHER THE CREW HAD FULL DEFLECTION OR NOT. WITHOUT COM TO THE FLT CREW THEY THEN WENT RUDDER R AND AGAIN THE INSPECTION STRIPE APPEARED VISIBLE AND PARALLEL. NOTIFIED CREW THAT ITEM WAS DEFERRABLE AND WAS BEGINNING PAPERWORK WITH MAINT CTL. WITNESSED CREW APPEARED TO BE VERIFYING RUDDER DEFLECTION WHILE I WAS COMPLETING DEFERRAL. DISCUSSED THE DEFERRAL WITH THE FLT CREW AND THEY FELT COMFORTABLE AND CONFIDENT WITH IT AND HAD NO QUESTIONS. MAINT CTL CONTACTED ME LATER IN THE DAY AND TOLD ME THAT ACFT WAS FERRYING BACK TO ZZZ BECAUSE THE CREW WAS NOT COMFORTABLE WITH THE INDICATION FOR L RUDDER TRAVEL. APPARENTLY; ACFT WAS MODIFIED TO INSTALL THE WITNESS INSPECTION STRIPES FOR RUDDER TRAVEL INDICATION TO ALLOW FOR THE DEFERRAL PROCESS. THE ACFT WENT IN FOR PAINT JOB IN APRIL 2008 AND SOMEWHERE BTWN MODIFICATION DATE AND APRIL 2008 THE INSPECTION STRIPE FOR L RUDDER INDICATION HAD BEEN MOVED FROM ITS ORIGINAL LOCATION. SO WHEN VISUALLY CHKING RUDDER TRAVEL INDICATION FROM THE GND; L RUDDER TRAVEL WAS NOT FULLY PARALLEL WITH THE WITNESS STRIPE. IT WAS LATER FOUND RUDDER CTL SYS WAS FREE OF ANY DEFECTS. THE RUDDER INDICATION POTENTIOMETER WAS ADJUSTED; AND THE WITNESS STRIPE WAS REPOSITIONED TO THE CORRECT INSTALLATION.