Blew the fuse ? You mean in the wiring, not the printer ?
If this is so read on. It's important !
The wallwart probably has a ground fault, or it used to. Now it might be running through some leakage paths and able to deliver 18V without load. You must load it with something, A 50 ohm would do but would have to be like a 20 watt. best you use a 100 watt regular light bulb. When not heated it should be way less than 100 ohms and will provide a load to see what happens. If the 18 volts drops like a rock it is the adapter, but then test by substitution, you should be able to find an
18 volt source somewhere.
There is one problem, it might not work if the adapter fried the printer board. In this case you are lucky that the PC works, and you will be lucky if the printer port works when you do get another printer.
The good news is that even if it did blow out the port, whether USB or LPT, you can get add on cards so you won't have to scrap the motherboard.
If I had to but a new printer I would look into something other than an HP unless it was a laser printer. They are good, but it seems there is no support for parts or anything, except of course ink cartridges. Some of their cartridges were setup so you can't even refill them I heard. I got an HP 1100 laser and when it runs out of toner I will be right there with a drill and some copy machine toner.
If I become a captive customer I never buy from the company again, and indeed I will NOT buy anything HP except for a laser printer. I don't want their burners, PCs, nothing. Just the laser printers, and they are overpriced.
When you buy an inkjet printer you are getting something like a VCR, cheap. As I tell people when they ask what to buy I tell them "It's all cheap, so get it cheap, minimum money for what you want it to do". Buy a VCR from a "good" company ? why bother they didn't build it.
Don't get me wrong, HPs aren't bad printers, but the extra money they cost is a waste, and I found the support to be no better than the others.
JURB