Maintenance Station, Schmaintenance Station!!!
I have a 1204, 1304, and a 1604. I do not pay ridiculous maintenance contracts or ridiculous service calls. Two were bought used and one I bought new 7 years ago from signwarehouse and I have printed like crazy with it. I have no formal training in these printers other than I use them daily in my sign business.
If you haven't messed with anything else on the machine, for the first 5 years or so 99% of the time it's the maintenance station, or more specifically the cap on the station. The rubber gets stiff over time and will no longer seal against the head. You can replace the cap only on the station for about 30 bucks, or the maintenance station for $280 to $380 off ebay if you are a little price savvy. Don't pay OEM Pricing, ($600) or (100)
Take the side cover off at the panel.
Take the two hoses that exit the pump to the black part above the waste ink tray and pull them out of the black 'receiver' or whatever you want to call it.
Put a plastic or other solvent proof "T" onto those two hoses in effect bringing them into one single hose that you will have to add on. Make sure the one single hose is also solvent proof silicone.
( a good thing to use is fuel proof silicone tubing that they use in .40 size gas model airplanes.)
After you do that leave the single line long enough to exit the bottom of the machine by drilling a hole in the plastic hand hold under the chassis.
Now you accomplish three things: You will only have to change your waste tray pads about 1/10th of the time as normal, and secondly you have a vacuum line that you can hook a large plastic or glass syringe to and check your maintenance station from time to time to make sure the head is sealing good. Finally, every time it runs a cleaning cycle you can see the ink moving and know things are working as they should. When not in use run the longer waste line into an old alcohol bottle or something to catch waste ink from cleaning cycles and empty as needed (like the 1304 and 1604 do.) Now only the ink from the wiper goes into the waste tray.
If the printer isn't printing well, put a syringe on the exit line and try to suction it. If maintenance station seal to head is good, you will pull ink and it will be difficult to pull the syringe. If it is not, you will hear it pulling air and it will be easy to pull. The techs do this sometimes to prime the system without clicking the percentages off of your cartridges. You can get clogs in the waste line that will prevent ink from pumping properly, you can get clogs in the small lines that run from the cap, down to the pump, etc. MOST of the time the problem is at the cap or below. I have rarely seen anything from the head all the way back to the ink cartridges, except for an occaisional o-ring malfunction and one color won't stay primed. It is usually all in the down line starting with the cap at the bottom of the head.
These things are qwerky. NOT USING ONE is way worse than running the dog mess out of it. They don't like to sit idle.
This weekend I bought a VJ1304 in pristine condition that the owner had let sit for too long (he thought) I bought it sight un-seen other than pictures for $1750. I drove 8 hours and picked it up. Took it to a friend's shop in a neighboring city and had it printing like a new one within one hour. The bottom end was gooped up, large buildup of ink on wiper, and overflowing off cap, etc. I spent ZERO dollars on parts. I just made sure some of the tubing was clear on the bottom end, cleaned all the goop off best I could and BOOM> new printer. The life times were all full on the internal counter for head, pump, and motors. There are many more out there like this. Knowledge is $$$$ Learn your printers inside and out and you will save big. Purchase a service manual offline on ebay in pdf format and learn it.
Just my 2 cents. !