Repair and disassembly guides for Epson printer. The company was founded in 1942 as Daiwa Kogyo, Ltd., but merged with another company in 1959 to create Suwa Seikosha Co., Ltd.
Black printing on WF 3640 got vague (other colors fine), checked ink level (OK), cleaned heads and nozzle, etc, then inserted new black cartridge and still no joy?
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