1. You have availed loan which you shall have to repay with agreed interest within agreed period,
2. You can not call it security cheque for the mere fact that it was blank but was signed by you,
3. If you sign a unfilled up cheque and handover to someone, it is imperative that you are giving him the right to fill it up at his suitable date which he has done in your case,
4. You can only escape your liability to pay for the dishonourded cheque if you can establish that the said cheque was not issued against any of your dischargeable liability,
5. Being 60 years old is no ground for escaping the repayment liability,
6. Talk to the Bank and try to settle the matter amicably.