Thank you, Trigger for that explanation. I came to realize that the purge unit was not working properly. After several test prints, the black suction pad was pooled with black ink while the colored ink pad was 'dry.' When I examined the printhead, there was a large amount of black ink clinging around the long, thin print nozzle. I concluded that this excess black ink was not being cleaned from the printhead properly and was somehow smudging the paper at the bottom of the printed side.|
Taking the MP530 apart was much easier the second time as you indicated. This time I removed the purge unit which was held in by just two screws. I disconnected the long black tube and found another plug of dried ink in the plastic orifice where it connects to the body of the purge unit. A bit of alcohol on a Q-tip seemed to dissolve the dried ink, but I couldn't be sure. Neither was I sure that there wasn't another clog somewhere else in the device. I did not want to take the purge unit apart to clean it thoroughly. I was afraid I'd never get it back together again in working order. I was tempted to reassemble the printer with the second clog cleared and give it another try, but decided to sleep on it.
The next morning, convinced that the root cause of my problem was a faulty purge unit, I went on-line to find out the availability and price of a new purge unit, thinking that if the price was reasonable, I'd buy a new one. I found Beck's CRS in Glenview, IL. They had the purge unit for $32.50 + tax. To me that sounded very reasonable considering that one PGBK ink cartridge costs over $20 at OfficeMax. They also had the blotter kit with the clear mylar shield which, when installed properly, prevents ink from smudging the back of the printed page. It was priced at $14.99 + tax. Again, very reasonable. It's clear to me that the cost of repairing printers is not the cost of parts so much as the cost of labor. Knowing that my printer would have potentially years of life left if I could get it working again, I coughed up the $50 for a new purge unit and blotter kit.
I was a bit confused as to how to install the mylar shield. The purpose of the shield, the presence of a small rectangular shaped cutout in the shield, and two adhesive strips along the edges of the mylar strip were the clues I needed to properly install it. A call to Beck's confirmed my reasoning. The shield is fastened by the adhesive strips over the black print platten. The rectangular hole allows the center ink drain tube to pass through the shield. The kit also contained a short (1/4") piece of clear tubing and a connector. I can only guess that this tube is meant to be attached to the end of the black drain tube, maybe to provide a larger diameter opening at the end of the drain tube to prevent clogging??
Installing the new blotter was like solving a jigsaw puzzle. The blotter comes in several uniquely shaped pieces that have to be inserted in layers in the bottom panel of the printer in the proper order. There were no instructions with the kit, but the shape of the molded plastic bottom panel provides sufficient clues as to how the blotter should be assembled. The purge unit went in with no trouble at all. Note, the long black tube is not included with the new purge unit.
Having assembled the MP530 once before, doing it a second time went really fast. I had to be careful not to proceed so fast that I overlook a wire connection or two. Taking a few digital camera shots of the unit at strategic points in the disassembly is very useful when it comes time to reassemble the unit. Also, a magnetic tipped Philips screwdriver is a must.
I had seriously considered buying a new Canon MX870 printer when my MP530 went on the fritz. It can be had for just over $200 with a set of ink cartridges as an internet purchase. In the end, I spent $100 to refurbish my MP530 which is now working perfectly. But more than that, I learned a lot about my Canon printer, how to take better care of it and how to fix it when it goes bad.