Brush won't turn.

A common problem is for hair to get wrapped around and forced into the end bearings which causes the motor to work harder or drive belt to slip. Cleaning the hair out can be a short term fix but new bearings might be needed. It's also a good idea to replace the drive belt at the same time as the slipping belt is probably not going to perform well even with new bearings.

I can't tell for sure from the pictures, but there are two possibilities - the drive belt to the brushes broke, or the brush can't turn due to excessive hair wrapped around the shaft. If the belt is OK but the brush does not turn, you should smell burning rubber.

If the belt is broken, you have to remove the bottom plate to expose the brush, remove the brush and the broken belt, and replace the belt, and put it back to gether. While you have the brush out, now would be a good time to clean it - remove the hair, etc from the brush and around the shaft. Good Luck!

There is a good chance the belt is broken. The reason belts break is because the brush seizes up due to hair wrapping around tight at the ends of brush. Inspect closely with a flash light to check for this.

Yep - that's usually the culprit if the brush stops turning. However, pull off the skid plate (bottom panel) and make sure you haven't picked up any string or some other obstruction that's wrapped itself around the brush & stopped it from turning. Things like hair/string don't always end up in the bag/bin sometimes if they're long enough they just wrap themselves around the brush.

The turbo brush may just need to be cleaned. If hair or other large debris gets wrapped around the brush, it can prevent it from spinning. Since the top of the turbo brush is clear, you can look in and see if there is a lot of hair wrapped around the brush. If so, you can open it up by removing the two screws on the bottom of the brush and popping the clear cover off, then cleaning all the debris from the brush (scissors work well if its hard to get dog hair off). Be careful to see how the brush goes back together as you take it apart.

If cleaning the brush doesn't fix it, the belt might be broken. As you're looking at the top of the brush, there is a little belt that goes from the brush itself to the large blue/green gear (it's red on some models) so that if you reach your hand in and turn the gear, the brush should spin. If this belt is broken or missing, it will need to be replaced. You can probably find a replacement belt online, or you can order a whole new turbo brush from the Bissell website for $24.99.

If it is a smell of burning rubber - most likely your vacuum belt is overdue for replacement.

At this point - remove the brush roller, remove the old belt, clean off your brush roller and remove any string or hair that may be bound up around it (usually around where the belt goes or on the sides), and put on a new belt. Your Kirby should act good as new if your bag is replaced at the same time.

If the brush roller has too much string and hair wrapped around it, many times the brush roller will not spin as fast as the belt is driving it and you will get that burning smell.

I have had problems with the belts on my Mach 5 overheating (smell of burning rubber) and also with the motor overheating and shutting down.
I learned the hard way that one of the issues might be that the roller/brush on the bottom of the unit has a metal bearing inside the roller/brush that can become clogged with hair (both human and pet hair) which effects performance of the unit.
Another item to check is if your dust filter is not plugged up which is located behind the removable dirt cup. This is the cup that you remove that collects the dust/dirt/hair from your floor. Take the removable dirt cup out by depressing the gold button and then look behind where the dirt cup sits for filter. This can be cleaned out by washing it with soap and water in the sink but make sure you let it dry overnight before placing it back in the machine. This probably causes some of the overheating when not enough clean air is passing through the machine.
It’s fairly easy to fix.
Lay the vacuum on the floor so that you can see the roller/brush. Then remove the phillip head screws that hold the protective plastic plate over the roller/brush. (There are about 6 screws that hold this plastic protective plate in place) Also, you will be removing the (1) screw that also holds the plastic plate over the belts. There are (2) belts that you can remove and when in doubt replace these (2) belts for around $9.00.
Once you have the protective plastic plate off that covers the roller/brush disconnect the belt is around the roller. Take the roller and cut off any hair that is wrapped around the roller. Next, grab the roller by each end and twist the ends caps and (1) of the ends will unscrew. Once you have unscrewed one of the ends remove any hair or dust that is trapped under this cap. (Be careful not to lose the small metal washer that sit on top of the bearing)You will notice under this cap is a metal bearing that can become clogged and jammed with hair. The hair should come out fairly easy and allow the brush to spin fairly easy once you have screwed the end caps back in place test that it spins freely. If it doesn’t spin freely replace the roller/brush with a new one for about $23.00.
When you put the belts back on the thick rubber one (Belt # 40201-271) has probably become stretched and should be replaced for about $3.00. The small diameter belt that goes over the roller/brush probably does not usually need to be replaced and does not usually fit very tight. I have heard that people will take the small roller/brush belt and turn it upside down to get a better fit.
I just did this on my Mach 5 and it runs like a new machine. I did end up replacing the roller/brush head.
Hopefully you will find this useful.

I have had problems with the belts on my Mach 5 overheating (smell of burning rubber) and also with the motor overheating and shutting down.
I learned the hard way that one of the issues might be that the roller/brush on the bottom of the unit has a metal bearing inside the roller/brush that can become clogged with hair (both human and pet hair) which effects performance of the unit.
It’s fairly easy to fix.
Lay the vacuum on the floor so that you can see the roller/brush. Then remove the phillip head screws that hold the protective plastic plate over the roller/brush. (There are about 6 screws that hold this plastic protective plate in place) Also, you will be removing the (1) screw that also holds the plastic plate over the belts. There are (2) belts that you can remove and when in doubt replace these (2) belts for around $9.00.
Once you have the protective plastic plate off that covers the roller/brush disconnect the belt is around the roller. Take the roller and cut off any hair that is wrapped around the roller. Next, grab the roller by each end and twist the ends caps and (1) of the ends will unscrew. Once you have unscrewed one of the ends remove any hair or dust that is trapped under this cap. (Be careful not to lose the small metal washer that sit on top of the bearing)You will notice under this cap is a metal bearing that can become clogged and jammed with hair. The hair should come out fairly easy and allow the brush to spin fairly easy once you have screwed the end caps back in place test that it spins freely. If it doesn’t spin freely replace the roller/brush with a new one for about $23.00.
When you put the belts back on the thick rubber one (Belt # 40201-271) has probably become stretched and should be replaced for about $3.00. The small diameter belt that goes over the roller/brush probably does not usually need to be replaced and does not usually fit very tight. I have heard that people will take the small roller/brush belt and turn it upside down to get a better fit.
I just did this on my Mach 5 and it runs like a new machine. I did end up replacing the roller/brush head.
Hopefully you will find this useful.

It could well be the dog hair. You'll need to remove the roller brush and completely clean it off with the hair which sounds like it has wrapped itself around the brush and the brush end washers. Check that the entire roller brush is completely clear and if any dirt is found at the sides, remove it.