Maintenance of a Pump Head without Seal Wash

When

In case of maintenance or pump head internal leaks

Tools required

Qty.	p/n	Description
1	8710-0510	Open-end wrench 1/4-5/16 inch
1		Hexagonal key, 4 mm
1	01018-23702	Insert tool

Parts required

Qty.	p/n	Description
1	5063-6589	Metering seal (pack of 2) for 100 µL analytical head , OR
1	0905-1420	PE seal (pack of 2)
1	5063-6586	Sapphire piston, 100 µL

Prerequisites

Switch off the pump at the main power switch.
Open the doors of the module.
Use an optional solvent shutoff valve or lift up solvent filters for avoiding leakages.
Remove the Pump Head Assembly.

NOTE

Both pump head assemblies use the same internal components. In addition, pump head A is fitted with the purge valve. The following procedure describes the removal and disassembly of pump head A (left). For pump head B (right) proceed in the same way and skip steps that deal with the purge valve.

Place the pump head on a flat surface. Loosen the lock screw (two turns).
While holding the lower half of the assembly (piston housing), carefully pull the pump housing away from the piston housing.
Remove the support rings from the piston housing.
Lift the housing away from the pistons.
Check the piston surface and remove any deposits or layers: clean the piston surface with abrasive paper and rinse with 2-propanol. Replace piston if scratched.
Using the steel side of the insert tool, carefully remove the seal from the pump housing.
Using the plastic side of the insert tool, insert new seals into the pump head.
Place the support rings on the piston housing. Note the correct position of the pins on the support ring.
Place the pump housing onto the piston housing.
Insert the pistons and carefully press them into the seals.
Tighten the lock screw.
Install the pump head, see Reinstall the Pump Head Assembly.

21-Jun-2025