Functional Description - Pressurized Coolant Bottle

A multi chambered liquid coolant receiving bottle unitized from upper and lower plastic parts forming part of the closed coolant system of an internal combustion engine. When unitized the bottle comprises a pressurized coolant de-aeration chamber separated by a convexly curved stationary pressure wall from the overflow chamber. The chambers are arranged laterally side-by-side and are hydraulically connected to one another by a hose external to the bottle. The upper plastic part forming an upper portion of the coolant chamber supports a coolant filler neck that operatively mounts a pressure cap thereon. The pressure cap has a lower primary seal, an upper secondary seal and a vacuum breaker valve and cooperates with the filler neck so that coolant is transmitted to the overflow chamber from the de-aeration chamber when the coolant of the system expands and from the overflow chamber to the de-aeration chamber when the system coolant contacts and creates a vacuum.