My iPod's battery died a few days ago and I opened the case to install
a new one. The installation went smoothly and now the iPod works well
in regards to battery, but the it doesn't sync e. When I connect it to
my computer it flashes "Ok to Disconnect". It's out of warrenty so I
can't replace it. The last time I uploaded new songs was about 2 weeks
before the battery installation, so I don't know if I damaged
something when I opened the case but I find it hard to believe.

I found an article in apple's support website and tried everything
they suggest(http://docs.info.apple.com/article.html?artnum=61711); I
tried to press and hold the "Menu" and "Play/Pause" buttons
simultaneously for approximately 10 seconds to reset the iPod. It
didn't help. I downloaded the iPod Updater to restore it, but the
computer doesn't recognize it's connected. I also checked it with
other computers to no avail.

I believe the problem has to do with the firewire port. The guys at
PDAsmart.com have describe this problem on their website: ?There is no
strain relief on the firewire port attached to the mainboard. The act
of just inserting and removing the firewire cable stresses the 6
connections to the mainboard every time you do it. Over time, the
solder joints that keep the port connected to the iPod's board
providing signal and power between your iPod and the host or charger,
are broken causing a failure. If your iPod will not charge or if your
computer cannot "see" your iPod anymore and you've tried all of the
normal troubleshooting steps, it is probably due to a damaged firewire
port.?  They offer a service where people send their ipod and they fix
it for 55$. The problem is that I?m currently stationed with the
israeli corps in the middle east and this solution would turn out to
be quite expansive. I?m looking for information on how to solve this
problem without sending it to them. I have no trouble using a solder.
You might even be able to get this information for the guys at
pdasmart.com  ( (512) 258-4500). That?s about it, Thank you!

If the i1394 port is the problem, you may be able to temporarily 'fix'
the cold solder joints by apply very slight pressure to the connector
while attempting to sync.

I tried, thanks for the tip. It didn't help.