Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 144

तदा then, दत्तवरः who received a boon, सः he, शैलः Mainaka, अवस्थितः he became stable, बभूव became, हनुमांश्च Hanuma also, मुहूर्तेन in a short while, सागरम् ocean, व्यतिचक्राम crossed over.

Then mount Mainaka, assured by Indra became secure. And Hanuman also crossed over the ocean in a short while.