We consider several hydrodynamic problems in unbounded domains where in the vicinity of the instability threshold the dynamics is governed by the generalized Cahn-Hilliard equation. For time independent solutions of this equation we recover Bogdanov-Takens bifurcation without parameter in the 3-dimensional reversible system with a line of equilibria. This line of equilibria is neither induced by symmetries, nor by first integrals. At isolated points, normal hyperbolicity of the line fails due to a transverse double eigenvalue zero. In case of bi-reversible problem the complete set ℬ of all small bounded solutions consists of periodic profiles, homoclinic pulses and a heteroclinic front-back pair (Asymptot. Anal. 60(3,4) (2008), 185–211). Later the small perturbation of the problem where only one symmetry is left was studied. Then ℬ consist entirely of trivial equilibria and multipulse heteroclinic pairs (Asymptotic Analysis, Volume 72, Number 1-2 , 2011, pp. 31-76). Our aim is to discuss hydrodynamic problems, where the reversibility breaking perturbation can’t be considered as small. We obtain the existence of a pair of heteroclinic solutions and partial results on their stability.