Help! I have attempted to drain the water from my Sterling Europa and need a bit of advice. My hand book tells me to pull back on a collar on a drain tube under the caravan and remove the plasitc end. The plastic collar will not budge, I have sprayed with WD40 but still no movement, to add to this difficulty the length of tube is very short and will not allow me to get a good hold, any suggestions will be very welcome. Could I simply cut off the end and allow the water to drain out? would the yellow drain tap under the seat then be sufficient to hold water once the caravan is in use next summer? Many thanks.