I purchased a Teac 4010 SU in 1968. It still sits next ot my other equipment and is used almost daily. In 1968 I bought a cleaning and head lubricating kit (Head cleaner, Rubber cleaner and Head lubricant). All three little bottles smelled exactly like denatured (isopropyl, rubbing) alcohol. When the bottles were empty I only filled one and that was with denatured alcohol. That was 42 years ago. The heads, tape guides, capstan and pinch roller have never been changed. All original and still pumping out fine sound...