Hi, I have a couple Apple ][+ that I received from my dad, who bought them at yard sales years ago and has stored in his attic. :-/. I cleaned them up and powered up with only 48k and disk controller in slot 6, single drive. I know the controller and drive are both good as I have another Apple ][+ (mine) that boots fine with them installed.

What should I be looking for on the main logic board? The computers try to boot from the drive, the head does its normal sounding initial clack-clack to return to track 0, but then spins the diskette forever.
Any socketed ICs I should try to swap from my working ][+? Any capacitors, diodes, etc?