Abstract: A flush control valve (10) for metering a predetermined amount of flush fluid, or other liquid, to a facility, such as a urinal, to be flushed. The flush control valve (10) has a push button cap (166) that is actuated to cause the primary valve assembly (33) to open and distribute the flush fluid from the inlet chamber (35) of the flush control valve (10) to the outlet chamber (36) of the flush control valve (10). Depressing the push button cap (166) activates a timing assembly (109), the interior working components of which do not come in contact with the flush fluid controlled by the flush control valve (10), thereby eliminating corrosion to that critical portion of the valve (10). The timing assembly (109) is pneumatically operated and is effective through a diaphragm (108) to actuate a pilot valve assembly (83) which controls the opening and closing of the primary valve assembly (33).