It depends on the model. In the Multifruit commercial juicer it is located on the back of the machine and you will need to remove the waste bucket to access it. In the case of the other juicers, it is located on the bottom or on the sides of the machine.
Make sure the juice tank is correctly in place and secured in its two bolts. If it is not properly secured, the most likely cause is that the bolts are dirty and have juice residue on them. If this is the case, apply a degreasing spray and leave it on, then move the bolts until they work smoothly.
