We study four bijections, which are promotion, evacuation, rowmotion, and rowvacuation, on generalized Dyck paths in rational Catalan combinatorics. We define the maps on generalized Dyck paths, which have their origins in maps on Dyck paths and non-crossing partitions. They include rotation, Kreweras complement map, Simion--Ullman involution on non-crossing partitions, and Lalanne--Kreweras involution on Dyck paths. These maps have an expression in terms of the four combinatorial bijections. By extending the bijection studied by D. Armstrong, C. Stump, and H. Thomas on one hand, and the correspondence of RSK type studied by B. Adenbaum and S. Elizalde on the other, we present the equivalence between the two bijections, promotion and rowmotion, on generalized Dyck paths through these bijection and correspondence. For this purpose, we provide an alternative description of the correspondence of RSK type in terms of Dyck tilings.