Valve assemblies (320; 420)are provided in a track tensioning system or in other applications. The valve assemblies allow pressurized fluid (grease or hydraulic fluid from a power machine) to be introduced or evacuated from the same port. The valve assemblies use either a single check ball or poppet configuration, or a dual check ball or poppet configuration which are moveable from a first configuration, in which fluid is blocked in one direction while allowing flow in the other direction, to a second configuration where the reverse is true. A track tensioning element (300; 400; 600) includespiston retaining features (515; 550) which retain a piston (505) within a track tensioning cylinder tube (510). A track tensioning element can also include a no-pre-load spring (605) positioned in-line with the tensioning cylinder (610). Disclosed track tensioning systems and track tensioning elements can, in various embodiments, utilize any combination of all or some of the disclosed features.