6
Maintenance
Replacing the Primary Pistons Seals
Thermo Scientific
Accela Pump Hardware Manual
67
Figure 49.
Removing the stacked components from the LDA body
Replacing the Primary Pistons Seals
When you disassemble the LDA, you must replace the primary piston seals.
Y
To replace the primary piston seals
1. To remove air from the springs, soak a pair of new primary piston seals (with the springs
facing upwards) in methanol or isopropanol for 5 minutes.
2. Remove the LDA from the pump (see
“Removing the LDA from the Pump”
on
page 60
).
3. Remove the holding hooks, bushings, and pistons from the LDA body (see
“Removing
the Holding Hooks, Bushings, and Pistons from the LDA Body”
on
page 64
).
4. Remove the used primary piston seals (see
Figure 52
on
page 69
):
a. Carefully insert a piston into the hole in the center of the seal, but do not push the
piston further into the bore of the displacement chamber.
b. Gently pry the seal out of the bore.
5. Carefully slide the piston through the bore in the holding hook. And then, with its spring
facing toward you, slide the white, secondary piston seal onto the piston (see
Figure 50
).
Lower displacement chamber
and check valves
Upper displacement
chamber
Outlet
module
CAUTION
Do not place the piston seals in an ultrasonic bath. Sonicating the piston
seals can damage the smooth surface of the seals.
Note
The secondary piston seals are reusable.
