SE will only boot when turned on side or upside down

[plat]

I thought it was all working fine when I was testing it open, it would boot multiple disks and run fine. It turned out only because I had the floppy drive sitting upside down (to access contacts on the bottom of the board I was testing). Now that it is fully back together and sitting upright it will immediately kick back out most disks, a handful it will start trying to read, show the happy mac then panic and kick it out. A couple times it has crashed on error code 6 on the top row, FF on the bottom while booting.

Just turning it on the right side boots every disk fine and also formats disks fine. If after it has booted I turn it back upright it continues to read and format disks fine. Only boot seems to be a problem and not sure what to think about that.

Any ideas or seen something like this before?

 

[plat]

Sorry a couple of revisions to that, when it was working opened up the machine was also facing screen down on the table so I don't know if it was the orientation of the floppy drive or the rest of the machine that made the difference there, but does seem most likely it was the drive and the positioning of the heads affected by gravity. And I mixed up the sad mac code in my head, it is actually 0000000F on top and 00000066 on bottom. I have been trying to decipher it but struggling to follow the information I find about it.

If in fact the heads are moving due to gravity to a bad position when upright, how would you go about fixing/adjusting that? I thought they were pretty well spring loaded and run on guides to keep them in position in any case.

 

[Byrd]

Hi plat,

Yep, that's an odd fault Have you stripped down the drive and cleaned the heads, re-lubricated the metal frame and checked if the eject gear is fully working - it sounds like it isn't engaging properly in the floppy mechanism but gravity allows the floppy to somehow get in the right position.

While there, I'd also check analog board voltages and for any dry solder joints - as in, maybe putting the SE into a different position than how it's usually sat for 40 years might suggest a dry/stressed solder - maybe another reason why the floppy doesn't engage as the voltages are out of spec ... and recap.

 

[plat]

Hi Byrd, and thanks for the reply. So far I've only done the bare minimum, opened it up originally to replace the smallest gear in the eject mechanism which had broken and I also lubricated the overall mechanism. I have to say I'm afraid of touching anywhere near the heads because if they got out of adjustment I would probably never get them back again (my understanding is it can be tedious and require special equipment). That is a good idea, if it wasn't the drive then something else must be loose and I can try looking for it.