My newly acquired PC Engine CD-Rom unit w/interface did not spin when I tested it out.... I was pretty dissappointed given I had already bought it on my trip to Japan
however, after reading this string, I too decided to pop the unit open...
After tweaking around, the inside of my unit looked pristine... so my engineering brain kicked in and figured the only thing I can really do is figure out which part drives the spinning... I then noticed there are 3 little gears that drivings the spinning motion.
I used one of my fingers to roll the gears... they won't budge but after i kept on trying.. it clicked and rolled with no problems
seemed like the gears had been stuck due to grease being dried up on it. excited, I put the parts back together and powered the baby up......
lo and behold now spins!!! I have been messing with some CD-Rom games and it works!!
so, i guess before we default to a dead laser head being the defect, for non-spin issues, gears can be a cause too - (fyi, symptons for me were: my drive powered up, said "PC" when I tried to run it, but nothing happened).
I hope this helps some other fellas to get his CD-rom unit to work!! good luck!!