SL-C6 Belt kit
With age, all belts become slack causing all kinds of malfunctions on the video. Symptoms include poor wind operation, inability to eject a tape correctly, tape counter failure.

When the belts fail, the whole lot should really be replaced. Sometimes though this is not always possible, either because the part is no longer available or because the unit needs to be fixed quickly. Cleaning the belts in a system is always a good idea.

Accessing the belts
Belt cleaning is not as easy as it sounds. Cleaning the belts themselves is very easy but getting to them is often quite difficult. Many of the belts in a machine are fairly straight forward to remove. Firstly remove the lid. From this position it should be easy to access several belts by removing one or two screws or a circuit. Take care when removing any 'C' clips as they are easily lost.

Secondly remove the bottom panel of the unit. On some machines you will now be able to see and remove the drive belts. However on other machines it will be necessary to first hinge up some circuit boards. Most boards are designed to hinge to allow service access to the underside of the deck. Look in particular for any service access screws normally coloured pink and often have an arrow pointing at the them on the board.

Do not be afraid to remove any connecting leads that may be required to hinge the board back but make a note so that they can be returned easily.

Note, some belts are extremely difficult to remove. In this case the belts are best cleaned in situ.

To clean the belts you will need some solvent, a lint free cloth and also some washing up liquid. Take the belt and inspect it for any physical damage such as a nick, tear or if it has perished. If there are any problems, the belt should be replaced.
cleaning fluid belt cleaning
Now add some solvent to the cloth and pull the belt through its full length about 10 times. A lot of black deposit will be removed. Do not attempt to continue this until no more deposit is removed.

Now take the belt to a sink a clean it using normal washing up liquid. This is quite important as it gives the belt back some of its stickiness.

Before replacing the belt, clean the surfaces that the belt was in contact with such as the pulley or roller using a cotton wool bud.

If the belt could not be removed from the unit, a cotton wool bud could be used to clean it in situ.

See also the pinch roller and head cleaning guide.