The unit uses a peristaltic pump, with two motor driven rollers alternately squeezing the hose and pushing material forward. You will need a #288623 replacement pump hose. This is for an RTX2000pi. The 1400 pi and 2500pi are very similar.
- Turn off the sprayer and wait 7 seconds for power to dissipate
- Unplug the sprayer
- Back off the material feed control to minimum so the tension on the hose is less.
- Relieve the air pressure in the air hose with the priming valve.
- Disconnect all the hoses from the front of the unit.
- Remove the material hopper.
- Remove the pump access door on the left side of the unit. It's the side opposite the switch side
- You will need a 3/8" nut driver to undo the bolt.
- You can rotate it up out of the way and then tighten the knob that also holds the plate so it stays up
- Remove the knob right next to the place where the hopper connects to the inlet port . This holds on the hose plate.
- Lift off the hose plate.
- You can slide the pump hose to the left
- Squeeze the pump hose together and remove it from the unit.
- Install the new hose (the clear part toward the rollers).
- Slide it to the right so the grooves on the hose couplings are held by the front plate of the unit.
- Replace the hose plate and reassemble the remainder of the unit in reverse order.
Here's a link to a video from Graco of the whole process.