A portable air compressor assembly includes a tubular frame having a pair of parallelogram shaped side sections. A support plate is connected between the side sections and horizontally positioned in a compressor normal operating position. A plurality of operating components connect to the support plate. A fluid pressure tank is supported perpendicular to the side sections and forward of the operating components. The frame envelopes the operating components' outer perimeter and angularly extends to a stop point rearward of the operating components. When tipped rearward to the stop point, the compressor assembly returns by gravity to the compressor normal operating position. An instrument and connector panel including an engine on/off switch is mounted in a protected position. Wheels and structural feet are removable and a handle is retractable and removable for shipping.