Thought I would never find a copy of the Technics SX-EN2 Service Manual until I found Owner-Manuals.com. Price was very fair and I received the download promptly. While a photocopy, it is quite readable and includes all the pertinent information and diagrams. Thank you Owner-Manuals!
Very good quality scan of the document. I am very pleased with what I got.
Text excerpt from page 3 (click to view)
How to Adjust the Rotating Phase of the Gear, Main Cam
1) Push down the hooking catch of the CHAS. MECH, and remove the TRAY. 2) Align the arrow mark of the Gear, Main Cam with the black round mark of the CHAS, MECHA as shown below. 3) Confirm that the Slide, Mech Cam is located in the right position, then insert the TRAY gently. Caution: If the rotating phase of the Gear, Main Cam is incorrectly adjusted, the chucking operation and tray movement will have malfunction.
Align the arrow 2 mark with the black round � mark.