How do I refurbish the ink absorber pads on a Canon MG3600 series?

Although not directly addressing your issue, here is some good information for troubleshooting the Pixma MG3620.

TROUBLESHOOTING TIPS FOR CANON PIXMA MG3620 PRINTER

Description of Trouble with this Printer (any or all of these):

1). Straight lines across the page were not straight (random misalignment)

2). Some small print was not clear (ghosting)

3). Some words were not printed properly (partially or completely missing)

4). Occasionally whole sentences were not printed (as if they were blocked

       out by post-its).

5). Printed page not completely ejected and stuck in the printer. Pulling on the page did not release the paper until I shut off the machine. (see #4 below)

Recommendations by Canon Technical Support: (in this order)

1). Clean Encoder Plastic Strip (search YouTube on this topic for specific

       Instructions on how to perform this action).

2). Next to perform the Regular Print Head Cleaning. Do this action 2 times. Press and hold

      the STOP button until the yellow “Alarm Lamp” flashes 2 times, then quickly

      Release the stop button (Note – the Alarm Lamp is a triangular button on the

      Control Panel). Print Head Cleaning will begin.

3). To perform the Deep Head Cleaning, Press and hold the STOP

      button until the yellow “Alarm Lamp” flashes 3 times, then quickly release

      the stop button (Note – the Alarm Lamp is a triangular button on the

      Control Panel).  Deep Head Cleaning will begin.

     CAUTION: ONLY PERFORM THIS ACTION ONCE IN A 24 HOUR PERIOD.

     FAILURE TO FOLLOW THIS INSTRUCTION MAY DAMAGE PRINTER.

4). Roller Cleaning – (do this action 2 times): If paper does not enter the printer during a print function or it does not completely eject the page after printing, then perform the following instruction:

CAUTION: ONLY PERFORM THIS ACTION ONCE IN A 24 HOUR PERIOD.

FAILURE TO FOLLOW THIS INSTRUCTION MAY DAMAGE PRINTER ROLLER.

Press and hold the STOP button until the yellow “Alarm Lamp” flashes 7 times, then quickly release the stop button (Note – the Alarm Lamp is a triangular button on the

Control Panel), wait for procedure to complete (usually within 10 seconds.)

5). Nozzle Check Pattern:

Press and hold the STOP button until the yellow “Alarm Lamp” flashes 1 time, then quickly release the stop button (Note – the Alarm Lamp is a triangular button on the

Control Panel), wait for procedure to complete (printer stops making cleaning noise).

Printed Pattern should have 7 patterns: There should be a group of rectangular boxes with No missing lines followed by 6 color bars that should be solid color with no white line vertical streaks.

GOOD LUCK !!