Green light kirby vacuum

SOURCE: Engaging belt on Kirby G5

first things first...take the powerhead off of the front of the kirby. If you look at where the powerhead connects to the front of the kirby you'll see a large hook...turn the hook using the crank on the front of the powerhead so that the belt is pulled up and away from the brushes. The hook stretches the belt so that it can fit over the fan drive.

Next, place the two "feet" of the powerhead onto the "perch" on the front of the kirby....lock it on by turning the silver lever on the top of the kirby (the one under the hood/light)

then turn the belt lever from off to on.

the G5 should have a light on the powerhead that comes on (green) if the belt is spinning the brushes. That will let you know if you've got it on correctly.

SOURCE: how do you install the belt on the kirby vacuum

Step 1: 
UNPLUG YOUR KIRBY VACUUM CLEANER. Before you go any further, take your time with this belt change. It's not that difficult, just a little different than most other vacuums. These belts are very easy to find on the internet. Step 2: 
You should be facing the front of your Kirby vacuum. The height adjustment lever will be on your right. Push the lever all the way down. Lift the light hood with your left hand. Turn theKirby vacuum belt lifter counter-clockwise with your right hand. Unlock the accessory lock. The accessory lock is located under the light hood. Move the lock to the left to disengage it. Remove the front of the vacuum cleaner.
Step 3: 
Turn the vacuum belt lifter all the way clockwise until the belt drops down. Unlock the roller plate by releasing the two latches on the rear. Pull the roller plate up slightly and then off.  
Step 4: 
Bend one end of the roller bracket just enough to remove the roller. Remove this end of the roller. If you need to replace the roller take it all the way out. Remove any carpet fiber, string, or hair from the roller with a scissor.

Step 5:
After you have removed the old belt, slide the new one back on the middle of the roller. If you're Kirby vacuum cleaner has a belt indicator light, the roller will have a magnet built onto one end of it. It's very important to install to install a roller with a magnet on the same side as the indicator light. The roller actually will only fit into the roller plate one way.
Step 6: 
Place the roller back in the roller bracket. Place the roller bracket back and lock it into place with the 2 latches. Rotate the vacuum cleaner belt lifter counter-clockwise. You should feel the the belt catch. Look inside to make sure the belt is being stretched onto the vacuum belt lifter. Reassemble the machine. After you have reassembled your Kirby, turn the belt lifter cockwise, releasing the vacuum belt onto the vacuum motor shaft.

SOURCE: Kirby Sentria

If the green light is off, then its time to replace the band. This video shows you how.

SOURCE: ALUMINUM ON KIRBY VACUUM

You can take it to the nearest Kirby dealer to get it buffed out for about $25. Most of us use buffing pads on a bench grinder. The polishing compound can be found at Lowes or Home depot in the tools area next to the buffing pads. Three compounds are usually used. First a cutter, then a cleaner, then a finish polishing compound. You can get by pretty good with just the last two. Make sure you clean the pads between the different compounds. You can do this by gently placing a flathead screwdriver in to the buffing pad to clean it. Wear safety glass and an old shirt.

SOURCE: How to put a Kirby Vacuum belt back on

To put on a kirby belt all you need to do is put on the belt on the brushroll, put the brushroll into the housing making sure the marks on the end of the brushroll are the same. Take the spin dial in the front and "hook" the belt till the dial reads off. Put the head back on the machine and spin the dial to "on".