1. First, check if the clean tank leaks when it’s not installed in the machine. If it doesn’t, go on to step 2. If it does, try the following steps:
a) Unscrew the black cap & and re-attach. Make sure it’s screwed on straight and tight.
b) Check the tank for any cracks. If it’s cracked, you can replace it here: http://www.bissell.com/clean-tank-2038370?productid=2949
c) Check the circular “umbrella” gasket in the center of the tank on the bottom (below the Formula Fill Line). This gasket should be circular in shape. If it’s not, the gasket may be warped. If that’s the case, you’d need to replace the tank (see above link).
d) Did you use vinegar in the tank? If so, you may need a new tank. Do not use vinegar in the tank—it may damage the tank and gaskets.
2. If the tank doesn’t leak when it’s not installed in the machine, unscrew the cap on the clean solution tank and make sure the small black rubber gasket on the end of the cap is present. The small rubber gasket fits over the white “x” shaped piece. If this gasket is missing, the machine will leak water as soon as the tank is installed. You’ll need to replace the cap, which you can do by clicking here: http://www.bissell.com/clean-tank-cap-with-insert-2036800?productid=2949
3. If the gasket is there and your cleaner still leaks, please take your vacuum to a technician. You can find your nearest BISSELL® Authorized Service Center by clicking http://www.bissell.com/support/product-support/service-centers or by calling 1-800-237-7691, available 24 hours a day.