What was found
SJO - FLT 521 - WITH FLAPS SELECTED TO 23 DEGREES, LEFT FLAP INDICATED 23 DEGREES, RIGHT FLAP INDICATED 28 DEGREES. A/C ROLLED TO THE LEFT. WITH FLAPS SELECTED TO 35 DEGREES, LEFT FLAP INDICATED 35 DEGREES, RT FLAP INDICATED 42 DEGREES. A/C ROLLED RATE INCREASED TO THE LEFT, ON GROUND FLAPS INDICATED NORMAL IN ALL POSITIONS. REMOVED AND REPLACED FLAP CONTROL VALVE AND RIGGED IAW DACO MM. OPS CHECK OK. (M)