Remove fuel from burner by removing the sump drain plug with a 5mm Hex key.

Turn Airtronic Burner upside down and disconnect primer port tubing at base of fuel pump.

Loosen the four lower pump access plate 3 mm HEX nuts and remove the access plate.

Gently lift out the pump membrane being careful not to loose the small coil tension spring and retaining collar secured to the bottom side.

Install the replacement membrane using the collar and spring from the old membrane.  Seat the collar on the new diaphragm by gently pulling the tip until the collar snaps into place.  Re-secure the pump access plate and primer port tube.