Abstract: A wobble plate engine mechanism includes a stabilizer mechanism operating between a wobble plate and a mounting on the engine cylinder block or associated engine case. The stabilizer mechanism has first and second mutually inclined, elongate link means, the first link means having one end connected to the wobble plate by a first pivotal coupling and the second link means having one end connected to the mounting by a second pivotal coupling, spaced axially with respect to the mainshaft from the first coupling, with the link means being connected together at their other ends by a third pivotal coupling. The third coupling is centered on a bisecting plane for the wobble plate, the plane bisecting the angle between the wobble plate and a plane perpendicular to the longitudinal axis of the mainshaft.