Lutz Size 1 - 1/4", Operating Instructions Manual

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3.6 Maintenance Model 1", Band Clamp Version
3.6.1 Maintenance of Check Valve and O-Ring
. Flush and neutralize the pump to be certain all corrosives or hazardous materials are removed prior to any main-
tenance. This procedure should always be followed when returning pumps for factory service also.
. Remove the nuts (4) and washers (5) from the four long pumping cap screws (35). Suction check valve seats
and check balls (6, 7) are located inside of the bottom of the outer chamber (8). Gently remove and inspect
for excessive wear, pitting or other signs of degradation. Inspect valve seat and manifold o-rings (). Replace
if necessary. Discharge check valves are located inside of the bottom of the discharge elbows ( metallic), (3
non-metallic).
3. Non-metallic pumps only: To inspect the manifold o-rings () remove the band clamps (0) on either side of
the manifold () evaluate and replace if necessary. Then reassemble the manifold assemblies. Lightly tighten
fasteners. Align the single parts of the complete pump and tighten the screws in turn with the admissible torque
requirement. The check ball should fit into the curved portion of the valve seat and be facing upward when rein-
serted into the valve seat location.
Caution!
When using pumps built with PTFE o-rings always replace with new PTFE o-rings, since the original o-rings
may not reseal the pump. PVDF pumps need additional gaskets (34). These gaskets are adhesive backed.
Remove paper backing and apply to upper surface of valve seats as shown.
3.6.2 Maintenance of Diaphragm and Pilot Sleeve Assembly
4. To inspect diaphragms remove the band clamps (6) from the outer pumping chambers (8). If replacement is
necessary due to abrasion or rupture unscrew the outer diaphragm plates (9). Models that are built with PTFE
elastomers will have a PTFE overlay (30) that faces the outer pumping chamber (8) and a back-up diaphragm
(3) on the air side of pump. When changing diaphragms it is recommended to replace always both. Pumps
without PTFE will contain only the back-up diaphragms (3).
5. If a diaphragm has been ruptured and corrosive or viscous fluid has entered the air side of the pump, the com-
plete air system should be inspected. After removing diaphragms and inner diaphragm plate (33), the pilot sleeve
assembly (4,4,45-48) and diaphragm rod assembly (3,5) may be removed by removing the retaining plates
(49) (you may only need to remove one retaining plate) and pushing the entire unit out through the bore in the
intermediate (4). Diaphragm rod assembly must be unscrewed to remove pilot sleeve.
Caution!
To aid in reassembly use a non-synthetic, petroleum based lubricating grease without EP additives.
Maintenance Model 1", Band Clamp Version