Page 10
12/18/08
DKY
DATE
DATE
4010 320TH ST. PO BOX 189
BOYDEN, IOWA 51234
THE DRAWING AND ALL
INFORMATION THERE
ON ARE THE PROPERTY OF
DEMCO
TOLERANCES
PPVALVE
DRAWN BY
ENG APPOV.
DESCRIPTION
DRAWING. NO.
REV
SCALE: 1:5
SHEET 1 OF 1
_
PISTON PUMP
.X = .060 MIN. MACHINE SUFACE 250
.XX = ±.030 BREAK ALL SHARP EDGES
.XXX = ±.010 BEND AND DRAFT
±1°
UNLESS OTHERWISE
SPECIFIEDALL DIMENSIONS
ARE IN INCHES
THIRD ANGLE
PROJECTION
G
N
M
K
L
K j
I
PISTON WIPER REPLACEMENT
F
F
G
H
I
A
b
A
D
D
E
E
E
E
C
C
b
1. Remove small manifold clamps (A), top and bottom, then
remove the inlet and outlet manifolds (B). This exposes the
valves, inlet valves on bottom (blue) (C), and outlet valves on
top (red) (D). Remove valve o-rings (E) making sure valves
are clear of matter and in proper working condition.
2. Remove center large cylinder housing clamp (F). Separate
cylinder housings (G&H) and remove front housing (H) and
o-ring (I).
3. Remove stainless steel piston nut (J), and thrust washer
(K). Pull out the piston (L), and wipers (M) to examine.
Locate the piston wiper support ring (N) lodged in one of
the cylinder housings (G&H). If deep scratches or grooves
are worn into the surface of the wipers or piston they should
be replaced at this time.
4.
To reassemble:
Place large o-ring (I) over the flare on
the cylinder housing already assembled to the drive case.
Silicone can be used around the sealing areas for extra
sealing.
