Chapin TREE PRO Manuel D'utilisation Et D'entretien page 9

REPAIRING THE PISTON/CYLINDER ASSEMBLY
Collar
Figure 1
Piston
Cylinder
Intake
Upper
Valve
Plate
Outlet
Lower
Passage
Valve Plate
Figure 2
Pressure
cylinder base
rib
Piston cylinder tab
Figure 3
Figure 4
Protective
Dust Cap
Figure 5
Chapin Backpack Sprayer Operator's Manual - English
Pressure
Cylinder
1. Remove the piston cylinder assembly by turning the piston
cylinder counter-clockwise when viewing the sprayer from the
bottom. Caution: The piston cylinder may have sharp edges.
2. Check for vertical scratches on the inside of the piston cylinder
and the piston. If one or both are scratched replace them.
3. To replace the collar, push it off of the crown of the piston with
your thumb. You will see form fitted slots to install the new collar
on to the piston crown (fig.1).
4. There are 2 valve plates on the piston cylinder, one on the inside
of the cylinder and one on the outside top. The valve plates are
held in place with a screw and washer and can be removed
and replaced using a Phillipshead screw driver. The 2 o-rings can
be removed and replaced as well. Ensure that the o-rings are
positioned in the o-ring grooves in the piston cylinder.
5. Grease the 2 O-rings on the piston cylinder (do not get any grease
on the valve plate) and screw the piston assembly into the
pressure cylinder base. Screw the piston cylinder clockwise until
tight and the bottom O-ring is no longer visible. When properly
placed, the tab on the piston cylinder will line up with the rib on
the pressure cylinder base (Fig. 3).
6. Apply Petroleum jelly to the inside of the piston cylinder wall and
on the collar, and reinstall the piston assembly into the piston
cylinder.
7. Insert the piston at an angle with the leading edge of the collar
placed over the slot in the piston cylinder . Bolt the piston
assembly to the pump shaft using the lever bolts.
8. Replace the protective dust cap. Tighten the nut and bolt.
8E
Piston
Piston
Cylinder
Dust Cover