hi,

see there is no age age limit for applying in cat exam, and there is no mention of maximum year gap. the basic eligibility criteria for appearing in cat exam is you need to have graduation degree in any discipline with 50% marks in graduation. however some top institute like iims, sp jain, fms delhi and top bschool has gd and  interview session after clearing cutoff score of entrance test. so you may asked to explain the year gap. thats why be prepared for it. however you are definitely eligible for cat.