Manoj defeated Vietnam's Huynh Ngoc Vien to enter the last eight stage. Also advancing to the quarters were Rohit Tokas (64kg) and K Shyam Kumar (49kg).
While Rohit defeated Australia's Muhammed Demirkaya, Shyam got the better of local favourite Thani Narinram. Both Shyam and Rohit are former medallists at this event having won a gold and bronze respectively in the 2015 edition.
But it was early bowing out for former Asian champion Shiva, who ended up sustaining a cut above his eye before losing to Thailand's Sonchay Wongsuwan in his opening bout.
It was curtains for Commonwealth Games silver-medallist L Devendro Singh (52kg) as well. Devendro went down fighting to Cuba's Frank Zaldivar Santisteba in his opening bout.
In the bantamweight category, Mohammed Hussamuddin was defeated by Filipino Fernandez Mario.