I included a link on Youtube to my Nextra where I show how I clean the filter (watch it from 08:55 onwords). Just remove the kick strip and unscrew (philips screwdriver needed) the little screw on the filter itself, then turn it anti-clockwise but while you're doing this make sure you insert the kick strip underneath to gather the residual water. Repeat this operation 3 o 4 times until the sump is totally empty, make sure you don't let the kick strip fill up too much otherwise you'll be spilling water all over the place, so just turn the filter clockwise everytime you want to stop the trickle of water. It's not too complicated and it won't be too messy if you follow these instructions carefully. Good luck ;-)
I had a heavy knocking noise and found it to be the counterweight ( or stabilizer) whiich looks like a lump of cement, had come loose and was slapping around. Managed to tighten bolts holding it to the drum whiich solved the problem.
Click on Hoover (below FIXYA) on this website, type in your model number & search. You will get a shortlist; click on your model,below the page u will get Manual/Guides. Click on the blue, you have your manual on line. And dont forget to rate me on this great site.