Gilson 402 manual Noses, Changing the Piston, Maintenance

Maintenance

Noses	Piston rod
Piston
	Piston button
and
	Allen screw
Syringes
	Piston nose
	Nose holding
Changing the Piston	tool

Allen screw

Piston button

Piston rod

Support collar

Piston nose

Syringe barrel

Valve screw

6

1.Remove the syringe from the pump as described in Chapter 4.

2.Slide the piston out of the syringe barrel.

3.Remove the piston nose from the piston rod by carefully pinching the piston nose with a pair of cutters and gently pulling the piston nose off the piston rod. Take care not to damage the end of the piston rod when removing the nose. (It is possible to remove the nose by pinching it between the thumb and forefinger nails and pulling.)

4.Remove any remaining debris of the original piston nose from the end of the rod.

5.The 100 µL and 250 µL pistons have a narrow rod that may be damaged if handled incorrectly. In order to fit a new piston nose without unduly bending the piston rod, undo the Allen screw that secures the piston button to the piston rod. Slide the button down the piston rod to within 10 mm of the end of the rod where the new piston nose is to be mounted and re-tighten it in position.

6.Put the new piston nose in its recess in the piston nose mounting tool. The 100 µL and 250 µL piston noses use a common tool. One face of the tool has a recess for the 100 µL piston nose, the other face has a recess for the 250 µL piston nose.

7.Hold the piston button and gently push the end of the piston rod into the new piston nose.

8.Remove the piston assembly from the piston nose holder. Slacken the piston button and slide it away from the piston rod.

9.Dip the piston nose in distilled water and slide the piston assembly into the syringe.

10.Hold the syringe upright with the threaded end of the syringe resting on a flat, clean surface. Slide the piston into the syringe until the piston stops (the nose is level with the end of the syringe).

11.For the 100 µL piston only, insert the support collar. The support collar should be replaced after around 60 000 strokes.

12.Slide the piston button against the body of the syringe and tighten the Allen screw that secures the piston button onto the piston rod.

13.Slide the piston up and down in the syringe five or six times to ensure a smooth operation between the piston and syringe.

14.Remount the syringe on the pump as described in Chapter 4.

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