What was found
AFTER LANDING, THE THRUST REVERSERS AND BRAKES WERE APPLIED TO STOP ACFT. DURING DEPLOYMENT OF THRUST REVERSERS AND WHILE APPLYING REVERSE THRUST, EXPERIENCED AN ASYMMETRICAL PROBLEM WHICH CAUSED A LONGER THAN NORMAL ROLL AND DIFFICULTY STOPPING THE ACFT. CAUSE OF MALFUNCTION, FOUND JAM-NUT AT THE LT THRUST REVERSER HYDRAULIC VALVE PUSH PULL CONTROL CABLE TO BE LOOSE AND NO SAFETY WHICH CAUSED THE ROD-END TO BACK OFF FROM THE CABLE. THEREFORE EXTENDING THE CABLE BY .2500" WHICH CAUSED A MISALIGNMENT BETWEEN THE RIGGING HOLE AND THE OPERATING LEVER OF THE THRUST REVERSE VALVE. THE SAFETY OF THE JAM-NUT IS CALLED OUT IN THE SUPER 27, AMM 78-31-04. THIS ACFT HAS BEEN MODIFIED IAW STC: SA4363NM, SUPER 27 MODIFICATION OR VALSAN MODIFICATION, WHICH REPLACES THE POD ENGINES WITH JT8D-217C ENGINES AND WITH HYDRAULIC POWERED THRUST REVERSERS. DO A 1 TIME VISUAL INSPECTION OF THE JAM-NUT AT THE THRUST REVERSER PUSH PULL CONTROL CABLE. ENSURE THAT THE JAM-NUT IS TIGHT AND PROPERLY SAFTIED.