Ok so cars water temp guage is reading about a quarter or so and has been doing this for a few weeks,before it went to half and stayed there. Thought it would be thermostat so changed that and still nothing. Radiator pipes seem a little on the stiff side when running so I bled the system today after I fitted the thermostat and until fan kicks it there no different and after fan goes off they do same again, any ideas what it can be?