IF I knew what I was doing,which I don't, I would have a go at it mate. But from what I've read I've got to drain the system and start again. Apart from the fact I've nowhere to do that, I tried to fix it earlier and when I checked the temp gauge, it was a needles width away from being in the Red! That was enough for me, don't mind playing about but if I stuff it up, it's going to be one hell of an expensive lesson! What if it's not an airlock but something more sinister? I wouldn't have a clue! I may have already done damage letting it get that hot. I can sit and talk about cars all day long, mechanics/engineering however and I'm a very lost little boy
