I have am Eureka Super Plus Wide Track Bagless vacuum:
http://i1.ebayimg.com/07/i/001/47/f1/88c0_1.JPG
I can’t seem to open the vacuum to change the brush at the bottom since the brush cannot move so i need to change the belt but i can’t find somewhere on the vacuum to change the brush.
I believe there are 4 phillips head screws holding the bottom on. they are screwed in from the top of the vacuum into the bottom. On the photo you provided, at least two of them would be inside the recessed holes shown on the left and right of the top of the vacuum roller section (just above "power" and just above "12").
take an ax and beat it till it comes out.
Try google and put in your model #. You may be able to find a book on it. There should be a way to take the bottom off. Some come off by removing the cover or guard around it. There may screws underneath there holding the plate on. You’ll need the model # if you want to buy a belt for it.
How to change belt on Eureka
Step 1Locate and purchase the correct belt for your Eureka vacuum cleaner from the local grocery or department store. Vacuum belts come in different sizes according to your model of vacuum. Check your owner’s manual or the vacuum itself for your model number.
Step 2Turn your vacuum cleaner over so that the bottom of the unit is facing you. Remove the cover plate from the bottom by undoing the screws that are holding it in place with a screwdriver.
Step 3Locate the belt pulley rod near the back of the vacuum base coming out of the motor. With the vacuum cleaner base turned upside down and facing you, the motor and pulley rod should be up near the top of the base.
Step 4Slide the vacuum brush roller out of the slots at the bottom of the vacuum base and remove the old belt from the brush roller and pulley rod. With the brush roller off of the unit, clean the brush by removing any strings or cords wrapped around the tube.
Step 5Install the new belt by looping it over the belt pulley rod next to the motor and then looping around the end of the brush roller in the belt slot. Hold the brush roller and pull back on it to tighten the belt while you slide the roller back into the slots on the vacuum base.
Step 6Replace the base cover plate by snapping it back into place and securing it with screws. Turn vacuum back upright and turn it on to test the belt and verify the unit is working.