[drh4683]

Chris,

The belt that zenith originally used is nothing more than an o-ring. For anyone curious, the original zenith fine tuner o-ring is p/n is 32-46. I'm sure the original belt is on the bottom of the cabinet under the tuner area. The aged belt develops a crack and just falls off when someone attempts to fine tune the set. It probably broke when you were adjusting it, as I doubt that TV was touched in the last 20 years! I just buy a few from the local ACE hardware, you'll need a #20, which is 1-3/16 x 1 x3/32". If you want to get some strange looks at the hardware store, you can always bring the tuner assembly in with you so you can make sure it works OK. The employees will ask if you need help and they'll see you carrying this "thing" around with you and they'll wonder what you're doing. That might be a good opportunity for someone to advise you that we made the switch to digital television and that you should just get rid of the old TV you're trying to fix....

Zenith used the o-ring as its essentially eliminates any backlash in the fine tuning. Also, be sure to check the actual gear that engages on the channel strip. The nylon gear is pressed over a serrated shaft, 9 times out of 10, the gear develops a hairline crack down one of the splines and the gear slips on the shaft making fine tuning either impossible or intermittent. Just turn the fine tuner and watch to see if if you can spot the crack. I remove the entire assembly, which is very simple, pull the gear off, add a little drop of super glue to the shaft and push the gear on and give it a quick turn so it sets up. Problem solved. In the pics, this is a different zenith actuator, but the nylon gear Im pointing to is exactly the same on belt drive types.