An ink delivery system is provided for an inkjet printer. The ink delivery system includes a supply of ink and an inkjet printhead having a first port, second port and an ink ejection nozzle. The inkjet printhead is connected to the ink supply tank by a first fluid supply path. The first fluid supply path includes first and second check valves which permit ink to flow from the ink supply tank to the inkjet printhead, but prevent fluid flow in the opposite direction. The ink delivery system includes a second fluid supply path which is connected at one end to the first fluid supply path between the respective first and second check valves. The second fluid supply path is connected at its opposite end to the inkjet printhead's second port. The second fluid supply path further includes a bidirectional pump so as to direct fluid flow in either direction through the second fluid supply path. The delivery system operates in various modes including a re-circulate mode, pressure purge mode, maintenance mode and normal print mode.