As far as I was concerned this morning, tracing the water loss to the pump was good news. Obviously I would have preferred it to be a dodgy O ring on the coolant tank cap but as it wasn't the head gasket, I was fairly happy. Reality check. They put it together with Torx headed bolts. Order socket set for same. I'll need to get the fan off. Ok, lock up the pulley and whack the nut. OOps! My car doesn't seem to have one. The clutch is a close fit to the pulley and the expected 36mm nut isn't there. Refer to German manual. Looks as though there is only an Allen bolt to remove and the fan assembly comes off. Is this the case, please? The Haynes requires me to set no 1 cylinder to TDC and remove the TDC sensor. Is this right for the M605 engine? Pardon my ignorance but even allowing for two manuals, this job looks to have potential hidden problems so I would like to know what I am letting myself in for. Thank you for any advice.