Can't install OS 9 on CRT iMac after firmware update

Question

This is a bit long winded, sorry!
I bought a "working" 2001 iMac, 500MHz, slot-loader, 20 gig HD, CDRW off eBay (the CDRW didn't!) that ran in OS 9. With an external CDRW it worked well, booting the OS discs fine.
The previous owner had left his details on a supposedly deleted OS X account, so I decided to do a clean install to remove them with a supplied disc. I noticed in Utilities that a firmware update was available, 4.1.7, so used it, then did a clean OS 10 install, remembering to install the OS 9 drivers too. I bet you can guess what's coming!- yes, the OE discs wouldn't load OS 9.
Having read postings on this forum (thanks, guys!) I bought a retail version of 9.1 to use, the white/gold one with Sherlock, but this won't load either.
The main problem facing me now is that I can't update to a proper OSX without updating the firmware to 4.1.9, for which I need OS 9 installing!!! (I'd quite like OS 9 back too!)
I've reset the PRAM,and even wiped & reformatted the HD and reinstalled the 9 drivers again using the OSX disc and then powering down (you're not meant to, I know!) and still I couldn't load 9 up, trying both ways to load, just getting the "question mark on floppy" symbol.
Any help, please? Haven't tried target disc mode transfer yet, but could get another machine to do it.
Thanks for your patience with this matter, Mark Mac.

Answer 1

I had a similar problem once (I'll spare you the details!) and what I did in the end was this:
1. Take the hard drive out of the iMac and put it in a FireWire enclosure.
2. Erase it and put OS9 on it down the wire from another working Mac. You don't necessarily have to use the installer CD; you can just copy the OS9 system across from another Mac and it will work as a valid system.
3. If you don't think it installed properly (as mine hadn't) put the installer for the firmware update into the startup items folder of the OS9 installation.
4. Put the HDD back into the iMac and reassemble.
5. Turn it on, whereupon it should automatically start the firmware update, running natively in OS9. Delete the firmware update installer from Startup Items.
6. Update to 9.1 if not already, as that is the minimum for installing OSX
7. Restart in 9.1, introduce OSX install discs and begin installation.
I know all this sounds a faff, but it worked for me and is quite logical if you think about it - not much can go wrong as long as you don't wreck the iMac while taking it to bits. One extra tip: don't install anything later than Panther on an iMac G3, because it won't be happy. And even with Panther, you might want to consider installing using XPostFacto (see versiontracker) which helps older Macs cope.
Good luck - let us know how you get on.
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