6
12. If piston is theaded, screw the piston
onto the rod, hand tight. Insert the
spanner wrench and tighten by
lightly rapping it with a mallet.
Otherwise slide the piston on the rod
and screw the locknut on the rod
and tighten.
13. Place the piston rings at an angle
over the piston and slip them into the
grooves. For elastomeric type seals,
place the flexible seal into the top
groove. Flip the piston over and
repeat the process with the
remaining seal.
14. New cup seals are installed by
placing one side in the piston groove
and stretching the seal around the
circumference with the thin tool used
in disassembly. Make sure that the
lips of the seals face the outside of
the piston.
Bore
∅
(in.)
Tie
Rod
∅
(in.)
Rec.
Torque*
(ft. lb.)
1
1
/
2
1
/
4
- 28
8
2, 2
1
/
2
5
/
16
- 24
16
3
1
/
4
, 4
3
/
8
- 24
28
5, 6, 7, 8
1
/
2
- 20
66
10, 12
5
/
8
- 18
130
14
3
/
4
- 16
225
Table 3.
* Recommended torque values using MoS
2
lubricant with 0.12 coefficient of friction.
15. Cylinder body o-rings are easily
removed using a thin blade tool.
Care should be taken to avoid
damaging the surface finish in the
groove with the tool.
16. Metallic cushion sleeves can be
replaced by removing the snap ring
sleeve retainers.
Note the sleeve orientation in the
groove before removal. Some
sleeves are not symmetrical and
new sleeves must be installed in the
groove in the same orientation.
17. Shorter cylinders are more easily
assembled in a vertical position.
Insert the body o-ring in the cap
body groove and position the
cylinder body on the cap.
18. Place a ring compressor sleeve tool
on the body. Lube the piston O.D.
and the rings. Carefully insert the
piston into the cylinder body.
19. Install the body o-ring in the head
body groove. When properly
installed, the o-ring should remain in
the head when inverted. Grease will
hold the o-ring in place if required.
Place the cylinder head with tie rods
on the body.
20. Repeat steps 6 and 7 in “Replacing
rod seals” section.
21. Start the tie rod nuts until snug
against the head or cap and lay the
cylinder on its side. Secure the
cylinder horizontally into a vice or
clamped to a flat surface.
22. Tighten the tie rod nuts gradually in
a cross sequence pattern to equally
distribute forces around the cylinder
with a torque wrench. The required
torque values are listed in Table 3.
Check each nut a second time after
reaching full torque.
Table 4. Seal Compatibility with Common Fluids
Standard seal material is Nitrile and is compatible with most
applications. Optional seal compounds are Viton
R
and EPR. The fluid
compatibility of these standard and optional seal compounds is listed
below:
Class of
Hydraulic
Fluid
Standard & Optional Seal Compounds
Nitrile (std)
EPR (opt)
Viton (opt)
Petroleum base
Compatible
Not compatible Compatible
Phosphate ester
Not compatible
Compatible
Compatible
Silicone
Compatible
Compatible
Compatible
Water
Compatible
Compatible
Compatible
Water/Oil Emulsion
Compatible
Not compatible Compatible
Water-Glycol
Compatible
Compatible
Compatible
Ethylene Glycol
Compatible
Compatible
Compatible
Auto Trans. Fluid
Compatible
Not compatible Compatible
Auto Brake Fluid
Not compatible
Compatible
Not compatible
-40
_
F to
-65
_
F to
-20
_
F to
Temperature
Ranges
1
+250
_
F
+300
_
F
+400
_
F
R
E.I. du Pont trade name for fluroelastomer (FPM).
1
Maximum ratings for continuous exposure.
