Abstract: A six-cylinder swash plate air conditioning compressor having reciprocal double-acting pistons within a swash plate chamber positioned centrally between axially spaced front and rear cylinder blocks having intermediate suction and discharge gas crossover passageways in the cylinder blocks. The swash plate chamber provides a crankcase for receiving lubricant returned from the front head suction chamber by means of piston blow-by during the compression stroke of the pistons. The suction pressure in the crankcase is at a higher level than the pressue in the suction gas crossover passageway while being at a lower level than the pressure in the cylinder head gas discharge chamber creating the necessary positive pressure gradient to circulate the lubricant internally within the compressor.