they are really hard to force on, my hand were killing after i done mine. leave the side that will be attached in hot water a for around 5 minutes removed spray lubricant inside the pipe, put some rubber gloves on for better grip. when forcing hose on, slide bottom half at and angle so half the hose is on first and twist left and right until top half gets close. now the hard part, whilst the top of the hose it touching the radiator pipe, get a screw driver or something to lift the hose onto pipe whilst simultaneously forcing hose on the pipe. (this might take a couple of goes but has always worked for me)