Tale of the bad cap top and the frugal sign guy
I had a customer that never replaced his cap tops. He owned a SP-540V with high mileage.
He meticulously maintained the machine, but he didn't see the value of replacing the cap tops. After all, he always kept the gasket clean, and always poured cleaning fluid down the caps when doing a maintenance cleaning. He never had a print defect that could have been fixed by replacing the cap tops.
One monday morning--as he arrived at his shop--he was welcomed by a puddle of red ink on the floor and quite a mess in the machine.
The sponge on the red/yellow cap had swollen and deteriorated so much that it significantly contacted the nozzles on the head-- and the ink started wicking from the magenta & yellow cartridges.
Change your cap tops every 6-12 months, or when the sponges look overly swollen or damaged.