To try and be as fair as possible, I need to follow up on my Epson 4900 post. The old thread wandered a bit off topic, so I'm starting fresh.
First, I was disappointed by both Epson and their recommended service center here in Fullerton CA.
This site was WAY more informative about my printer than any other resource.
With my printer "condemned" to needing a new head by both Epson and the service center and unwilling to pay the $1,600 repair, I had little to loose and attacked my printer.
After disassembling the unit and removing the head block, any and all possible clogging was nearly instantly cleared by flushing a little water through the channels.
Reassembly, braving the purchase of a full set of inks so I could re-start/initial charge the unit - I figured it was still a 50/50.
Short answer - after an initial charge and a single nozzle check and normal cleaning, I was missing about four nozzles (total) after having had NONE of the nozzles printing
A few test prints and I had ALL the nozzles working again. An automatic head alignment and I was back in business.
NOT for the timid but I am back to printing.
The post here in the forums listing where to purchase the service manual and service software was absolutely essential and the only expense outside the cost of ink.
Very frustrating but a MUCH better outcome than it first appeared.
I still love the output from this printer, even if we now have a slightly less rosy relationship.