JLG 1850SJ, Service And Maintenance Manual, Page: 408 / 712

SECTION 5 - BASIC HYDRAULIC INFORMATION & HYDRAULIC SCHEMATICS
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3. Reinstall the swashplate/servo piston/bias spring
assembly in its original orientation in the housing.
Rotate the servo piston perpendicular to the swash-
plate, and at the same time compress the bias spring to
fit into housing pocket. Lubricate all sides of the servo
piston and its respective bore liberally with hydraulic oil.
Also, lubricate the flat face of the swashplate to prevent
premature wear during start-up.
4. Insert the input shaft (J010) through the bearing into
the housing. You may need to push on the servo piston
to rotate the swashplate in order to put the shaft in
properly.
5. Coat all parts with hydraulic fluid prior to reassembly.
COMPRESSING THE BLOCK SPRING REQUIRES ABOUT 350
TO 400 N [80 TO 90 LBF ]. USE A PRESS SUFFICIENT TO
MA INTAIN THIS FORCE WITH REASONA BLE EFFOR T.
ENSURE THE SPRING IS SECURE BEFORE ATTEMPTING TO
INSTALL.THE SPIRAL RETAINING RING. RELEASE THE PRES-
SURE SLOWLY AFTER THE RETAINING RING IS INSTALLED.
6. Install the inner block spring washer (K042), block spring
(K043), and outer washer (K044) into the cylinder block.
Using a press, compress the block spring enough to
expose the retaining ring groove. Wind the spiral retain-
ing ring (K045) into the groove in the cylinder block.
7. Turn the block over and install the hold-down pins
(K046), and ball guide (K047) to the cylinder block.
8. Install the pistons (K050) to the slipper retainer (K049).
Install the piston/retainer assembly into the cylinder
block. Ensure the concave surface of the retainer seats
on the ball guide. If you’re reusing the pistons, install
them to the original block bores. Lubricate the pistons,
slippers, retainer, and ball guide before assembly. Set
the cylinder kit aside on a clean surface until needed.
NOTE: Be sure to install the slipper retainer so it mates correctly
with the ball guide (concave side of the slipper retainer
against the conve
x side of the ball guide).
9. Set the pump on its side. Secure the end of the shaft
with one hand and keep it horizontal. Insert the cylinder
kit onto the shaft. While holding the shaft still, slightly
rotate the cylinder block kit to help start the shaft
splines over the ball guide and align it with the block
splines. When the cylinder block kit slides completely
over the shaft splines, reposition the unit with the flange
facing downward.
10. Clean the valve plate (B090) and endcap. Install the tim-
ing pin (J050) in the endcap and verify that it is properly
oriented with the split facing into or out of the slot in the
valve plate. The timing pin should be installed to 3.61 ?
0.25.mm [0.14.?.0.01 in] above the valve plate surface.
Apply a liberal amount of assembly grease to the back-
side of the valve plate surface to hold it in position.
Install the valve plate over the timing pin, check valve
(B092), and bearing cup (B010).
K050
K049
K047
K046
K041
K042
K043
K044
K045
P010
Fix the shaft
on this end
Slightly rotate
cylinder block
B090
J050
B091
B092
B010