Yeah, it's possible. Why is it rusty? Are you running your chain dry (i.e. un-lubricated)?
Unfortunately, and I left it in the heavy rain this past month to top it off.
If the bike has 8-9spd rear cluster, then you can easily disassemble the cluster and clean the cogs off
with degreaser and some nylon abrasive pads which should take care of the rust as well. If the cogs
are rusty then the chain is even more likely to be so. Flash rust goes away with a bit of lube and
riding. If the bike is 6-7spd it may have a freewheel, not easily taken apart. Just clean, lube and
ride it.
Yes the free wheel does not have a removable pulley or anything. But, you are saying just lube it and it will come off is that corrrect? Do you have a list of things I need to buy? I have lube.