Can I please peek your brain as I have no experience with this platform.
I am currently repairing a Macintosh SE which shows a number of issues. Issue 1 was RAM oxidation on one module, I think I sorted that and yesterdat the Mac was booting up happily every time. I only have the mouse, I could browse the desktop.
Second issue was the gummed up floppy drive. I fully disassembled it and cleaned (did not disassemble the heads, I basically detached the loading mechanism, washed it in white spirit and then re-lubricated it with lithium grease).
When I went to test it
1. The Mac boots to desktop but as soon as I move the mouse the finder menu opens and that's the last thing the Mac does and I have to power it off.
2. I don't have a Mac formatted 800KB floppy unfortunately. But I just wanted to check if the loading mechanism worked. So I disconnected the HDD and let the Mac reach the "question mark" part. At that point if I load an MSDOS disk, the disk loads fine, it spins fine. Then I hear two buzzing noise coming from - I think - the heads. Then the drive ejects the floppy. Is this normal behaviour for "I cannot recognise this disk"? If I manually move the head away from track zero (with the Mac powered off), the head goes back to track zero when it tries to access the disk.
Well, the loading mechanism works. The disk loads and unloads perfectly.
As the Mac sometimes fails to boot altogether - with the grey screen - I might want to check those RAM modules again but I had a completelty different issue before - picture corruption and "sad mac face" pointing to the oxidised slot.
Any help appreciated!