WD My Book Premium passed away?

For the last two years I have had My Book Premium 500gb External HDD partitioned (using Disk Utility) into two equal volumes that I have named MyBook 1 and 2 respectively. I use My Book 1 for for my Time Machine backup drive and  My Book 2 for odds and ends and my iTunes library.  My Book 2 get

Recently my iMac has been slow booting up.  I checked all my volumes (including my iMacs internal HDD) over for errors and found a number of serious erors in Mybook 1.  I was prepared to reformat this volume and start over with the Time Machine backups because this volume had corrupted before about a year ago. Anyway Disk Warrior got my MyBook working again for about a week however I recall that it mentioned DW reporting that it had made 'Volume Wrapper repairs where necessary" or something similar.

Anyway the other day both volumes disappeared from my desktop.  I fired up Disc Utility, then Disk Warrior but neither programme could see the MyBook Drive. Then my iMac refused to boot up.  I got the ‘white screen of death’.  The MyBook began making a faint clicking noise about once every second or so.  The only way to get my iMac to boot up was to disconnect my MyBook Premium HDD from the Firewire connection.  I couldn’t even boot from my Disk Warrior DVD unless the MyBook disconnected. 

I am thinking my My Book has died.  Is there any way to recover it even though my iMac won’t start up with it connected?

Here’s an update.  I’ve got it working again. I can barely believe it myself.

The iMac was off but I noticed that the MyBook was still spinning after several hours so I pulled the power cable out of the drive.  The spinning stopped but for some reason the round blue display on the front remained lit up.  In fact it only went out when I removed the Firewire cable from the MyBook leaving the iMac end in situ .  The MyBook was quite warm but not hot.

I decided to leave it alone overnight and went away.  Came home from work this evening.  Pondering about the problem I turn off Time Machine in the System Preferences pane and wrote the above account.  

An hour later I plugged the MyBook back in with the iMac running.  Nothing happened but I didn’t expect it too.  So, on a hunch, I restarted my iMac.  Lo, it fired up immediately.  Not very very slowly or stuck at the grey screen.  Both volumes appear on the desktop.  The only difference is both have the yellow and white Firewire icon, presumably because I have turned off Time Machine.

So my hunch is that Time Machine has an issue - not necessarily with Snow Leopard.

I spoke to soon.  It’s gone down again.  

iMac slow to start up (but at least it does start up now) and the drive just does a quick buzz every second or so.  Blue light on front is on continuously and neither Volume appears on the Desktop.  Disc isn’t spinning as far as I can hear unlike the other day when it wouldn’t stop until I removed the power connector.

Funny but it was working fine again yesterday.