i have just renewed the seals on the front timing cover for the water and oil ways on grand voyager 1997 3.3 as it overheated and that was the only leak i could find.After refilling coolant and roadtesting i notice the seperate expansion tank level keeps increasing which would suggest to me that it was pressurising.The fans work, the gauge reads halfway and theres no white smoke from exhaust.I could not find any bleed valves on cooling system so just filled system and ran it until bubbles stopped.Any ideas please?????