In this instructable, we replace the soap reservoir on a built-in kitchen sink soap dispenser with a bulk dish soap container. These reservoir bottles require messy refilling and they break easily. Typically, the soap is stored under the kitchen sink anyway so, this will remove unnecessary moving parts and makes refilling easier by simply replacing a bulk soap bottle under the sink.
Step 1: Remove the Pump Assembly and the Dispenser Reservoir
These are typically removed by pulling straight up on the dispenser. This is usually the first step in refilling the pump. The reservoir is removed by unscrewing it from under the sink.
Step 2: Measure the Diameter of the Pump Straw; Acquire Appropriate Flex Tubing
Alternatively, take the assembly to a hardware store that sells vinyl tubing. The goal here is to extend the pump straw by using a flexible tube that fits over or inside of the straw.
Step 3: Prepare the Bulk Soap Container
Most bulk dish soap container caps have a small jet that protrudes from the lid to direct the soap when the bottle is squeezed. Using a razor knife, cut the jet to match the diameter of the hose. Insert the hose into the jet and place the cap back on the dish soap. Ensure that the hose rests on the bottom of the soap container.
Step 4: Cut the Tube to Appropriate Length
For this step, shorter tubing is better. Place the soap container in the bottom of the sink and push the tube up through the soap dispenser hole (where the old reservoir was). Cut the tubing leaving 8-10" of slack over the dispenser hole.
Step 5: Tie a Loose Overhand Knot on the Tube
The knot prevents the soap from backflowing back into the container. Keep the knot loose so you can move it close to the pump after priming the line.
Step 6: Prime the Line
Set the soap bottle at higher than the sink. Create a siphon to clear the air out of the line. It is important that the loose knot is filled with soap.
Step 7: Insert the Flex Tube Into the Pump Straw
Place the bottle of soap under the sink where it belongs. Route the tube up through the dispenser hole and insert the flex tube into the pump straw. You may require silicone tape or glue to ensure an airtight seal. Like a broken straw, the pump will not function efficiently if the tube is not sealed.
Step 8: Install the Pump; Enjoy!
Slip the knot as close to the pump straw and pump dispenser as possible. Enjoy using your almost endless supply of dish soap!