Hi, Beko198 made a very in depth stripdown which is very handy.
The clutch is easy to access.
1) Use a coin or flat screw driver to turn the 3 grey plastic screws 90 degrees anti clock wise and remove the soleplate.
2) Remove the brushbar by lifting the right hand side out, tilting it up slightly and turning the brush as you remove it off the belt.
3) Remove the internal hose- The end with the grey piece pulls off and the other end connected to the brush housing twists off.
4) Remove the brush housing by rocking the joints up and down as you pull, it unclips on either side all the same.
5) Remove the clear U bend at the back of the vacuum, underneath the hose by unclipping it by the grey latch.
6) Using a torx T15 screwdriver, remove the 3 screws holding the black clutch cover on. Two screws are easily visible underneath the grey clutch know and there is one awkward to reach screw. It requires a T15 torx screwdriver about 3.5 inches long. This screw is accessible behind where the U bend sits.
7) Remove the clutch cover, it just comes away and you should now see both belts. There is a small rubber belt from the moor spindle to the clutch and the larger belt for the brush. Has the smaller belt snapped? If so, it's best to buy a replacement clutch. The clutch is easily removed as so;
8)pry off the grey brush control clutch knob from underneath the head and at the top of the head with a flat screwdriver.
9) The clutch can now be removed from the cleaner head by pulling on the belt(s). Be careful because the clutch can spring out because of the tension it's getting from the rubber belts.
And remember, no matter what breaks on your Dyson DC33, it CAN be fixed! Literally all parts are 100% replacable. This includes the moor, small tiny plastic bis, the main body, etc!
Hope this helps!