In the last post we took a look at a Sony TC-355 that I recovered from the recycle pile. After a thorough cleaning we were able to test it. Unfortunately, only the rewind function worked correctly, and it was obviously necessary to get inside the machine. Here is what we found:
A look at the guts of the tape machine reveals that there is one drive motor, several drive wheels, a primary belt, and lots of sliding and pivoting components. The whole thing was lubricated in the factory with a rather nasty grease that has since become petrified. The same sort of grease was encountered during the repair of a Zenith all-in-one phono/AM/FM machine from 1973 or so. That stuff may have been super-duper when new, but when it ages it becomes terrible.
The various sliding parts needed to be cleaned and re-lubricated with modern products. That was tedious, but not a problem. Spindles were lubed with special oil as directed in the owner’s manual which was readily available online. The big problem, however, is that the pinch wheel would not move to the running position. When the selector handle is turned to Forward for either Play or Record then small pinch wheel moves up and toward the drive capstan. The wheel pinches the tape against that capstan causing the tape to be pulled through the machine. Something is causing the pinch wheel to not pinch. I am willing to bet that it is bad grease.