Ok I stupidly decided to check the Thermostat whilst waiting for the Hose to arrive from Supplier to make sure it opens properly, Now I know why I should,ve left it alone 4hrs later arm cut to pieces the thermostat starts opening at about 90 degrees, maybe a little high please let me know if it ,s to high. Drilled a 3mm hole just for good measure seems to be general consensus of opinion, thermostat back in it,s housing, but here lies the problem When I removed the housing from the locating hole found an "O" ring which I assume seals the housing to the pump outlet cant for the life of me see how to fit it to reinstall it checked manual not a lot of help, any ideas??