14
D15-991-2400 Rev B
D/G15 & D/G17 Service (Hydraulic End)
NOTE:
The numbers in parentheses are the Reference
Numbers on the exploded view illustrations found later in
this manual.
This section explains how to disassemble and inspect the
hydraulic end (oil reservoir) of the pump.
CAUTION: Do not disassemble the hydraulic end unless
you are a skilled mechanic. For assistance, contact Wanner
Engineering (612-332-5681) or the distributor in your area.
CAUTION: The four socket-head capscrews (31) that screw
through the cylinder housing (25) into the pump housing
hold these parts together.
Do not remove
these four screws
except when repairing the hydraulic end.
NOTE:
The following service procedures refer several times to
the Wanner D-15 Tool Kit. We strongly urge you
not to repair
the hydraulic end of the pump without using the tools in this Kit
(available from Wanner Engineering or your local distributor).
Refer also to the list of tools and supplies in the Fluid-End
Service Section.
Service Procedure
NOTE: Before Step 1 Remove Pump Housing, scribe a line
on the perimeter of the cylinder housing and onto the pump
housing. This will simplify alignment during reassembly.
1. Remove Pump Housing
a. Remove the manifold and valve plate, and the diaphragms,
from the pump. Refer to the Fluid-End Service Section
b. Drain the oil from the pump housing by removing the
drain plug cap (28). Dispose of the oil properly.
For D/G17 only: Drain the oil from the pump housing by
removing plug (36), then tipping the pump up onto the
cylinder housing (25). Remove oil reservoir (39), clean
and set aside. Return the pump to its secure horizontal
position.
c. Check the shaft for sharp burrs. Smooth any burrs, to
prevent scarring the seals (47) when removing the shaft.
d. Reinsert two perimeter bolts (2) through the cylinder
housing (25) into the pump housing (39), at the 10 and
2 o’clock positions, to support the parts as the pump is
being disassembled.
e. Remove the four socket-head capscrews (31) loosening
alternately so the cylinder housing separates evenly from
the pump housing. Slide the cylinder housing out on
the two bolts (2) that were inserted for support in Step d
above. The preload on the piston return springs will push
the cylinder housing out of the pump housing. Remove
the support bolts and cylinder housing assembly.
NOTE: the piston assemblies will be free to slide out
of the cylinder housing, so keep the cylinder housing
orientated with pistons up, for later disassembly.
f. Remove the shaft assembly (45) sliding the shaft out of
the seals (47). The parts are heavy.
g. Remove the bearing adjustment plate (43) and inspect
the bearing cup (45A). Inspect all parts for wear, and
replace if necessary.
h. Inspect the cam and bearings (45), and the bearing cup
(45B) in the housing. If the bearings are pitted or binding,
or if the bearing cup in the housing is worn, contact
Wanner Engineering.
CAUTION: If a bearing cup or bearing cone is replaced,
they must be replaced as a pair or premature failure will
result.
2. Disassemble Pistons
Inspect and clean all parts of the hydraulic piston assemblies
(61). Replace all O-rings and any other parts that are worn
or damaged.
3. Reassemble Pistons
a. Drop a ball (59) into each opening in the bottom of the
piston assembly (60).
NOTE:
Using grease on the O-rings, and lubricating the
parts, will aid in assembly.
b. Insert a retaining washer (58) and O-ring (57) to hold the
balls in place.
c. Insert a valve plunger (55) into the valve cylinder (56).
Slide priming spring (54), spacer (53), and overfill spring
(52) over the valve plunger (55), inside the valve cylinder
(56).
d. Insert an O-ring (51) into the spring retainer (50).
e. Slide the assembled valve cylinder (56), valve plunger
(55), priming spring (54), spacer (53), and overfill spring
(52) into the spring retainer (50).
f. Slide the complete cylinder-and-retainer assembly into
the piston assembly.
g. Insert a piston return spring (49) into the piston assembly,
with the larger end going into the piston first. This is a
tight fit, and can best be done by “screwing” the spring
in counterclockwise.
h. Repeat the above procedure for the other four pistons.
4. Remove Shaft Seals (47)
Inspect the shaft seals (47) before continuing. If they look
damaged in any way, replace them. Remove by pounding
them out from inside the pump housing. Replace both shaft
seals at the same time. Clean the bore in the housing using
emery cloth or Scotch-Brite™.
5. Reassemble Pump Housing
(39), Cam Assembly (45),
and Cylinder Housing (25)
a. With the pump housing vertical and the baseplate
removed, set it with the open end up on a workbench.
Grease the groove at the face of the housing and install
O-ring (48). Set aside.
b. Set the cylinder housing, with the diaphragm pockets
facing down, onto smooth, clean, 4” high blocks. Insert
the bearing adjustment plate (43), with the bearing cup
(45A) and dowel pin (44) into the cylinder housing. The
dowel pin engages into the largest of the five slots in the
cylinder housing.
c. Insert the five piston assemblies into the cylinder housing.
