Sony 800K 3.5" drives: I/O Error Block #0002

[buggie@aix05.unm.edu (stephen e buggie)]

About two years ago, I bought a dozen used "Mac 800K drives." These are 
the older type of external drives, used on Mac Plus. Its a beige case, 
slim low height, no eject-button,and NOT plug-compatible with Apple II. 
I understand that the internal mechanism is identical to the Sony 800K 
mechanism in the platinum 3.5 drive, and I have transplanted the innards 
into platinum 3.5 drive cases with good results, in the past.

I tried doing this transplant with these drives, and none of the drives 
seems to work. The light comes on, the motor spins, and the intake and 
eject mechanisms work fine.

THE PROBLEM with all 12 drives is that they will not read or write disks. 
The rotation turntable motor works, but after a minute's spinning, I get 
an error message on the screen, 

                        "I/O ERROR BLOCK # 0002"

I have cleaned the heads and the mechanisms, and have tried the mechanisms 
in other casings, still the same error. Is anything easily fixable???
The drives are in excellent physical shape ---- good "kerchunk" intake and 
explusion of the disks. I am installing them correctly ---- 3.5 mechanisms 
known to work, work fine when installed in the casing.

Please advise me!   Thanks,   Steve Buggie      Gallup NM 	
buggie@unm.edu