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3-1-618 Page 10
Before starting a pump which has been idle for a long
period of time, drain any water accumulation from
crankcase by removing the drain plug and replacing
when clean oil begins to flow from the drain. Add oil
to proper level. It is recommended that the fluid end
of pump be primed to prevent excessive wear on the
pistons and liners when starting.
OPERATION –
The pump should always be started
slowly, with little discharge pressure; this gives oil a
chance to warm up and flow through all oil lines and
bearings. This warm-up is especially important
during cold weather operation.
The pump must not be operated at speeds exceeding
the rated speed on the nameplate. Horsepower
given in the bulletin must not be exceeded.
Application approval must be obtained from Gardner
Denver Marketing Department for any application in
which pump speed is below 50 RPM.
Fluid cylinders are secured to the frame by high
tensile strength connecting studs. It is important that
nuts on these studs be checked occasionally for
tightness. A loose or improperly torqued nut will
cause a stud to break under a pulsating load. For
proper tightening torques refer to page 26.
TAPERED SEAT VALVES
- This type of valve is
retained in the cylinder by the locking action of the
matching valve seat and deck tapers.
The valves should be examined regularly for
excessive wear and for coating or particle adhesion
that may prevent proper valve opening and closing.
A valve that is not sealing, opening and closing
properly, or a seat that is improperly seated in the
deck, can fail quickly by erosion of the valve, seat or
deck.
Access to the discharge valves is gained by removing
the valve covers on top of the cylinder. The retainers
or cages, springs and valves must be removed before
the seats can be inspected or pulled. The suction
valves can be examined by removing the cover on
the front of the fluid cylinder. The valve seats are
removed with a valve seat puller.
Wipe the tapered surface of the valve seat and pump
valve deck, in the fluid cylinder, with a clean cloth.
Lower the seat into the port taper and then lift slightly
and drop. If the seat drops straight, it will seize on
the taper sufficiently that it cannot be pulled up by
hand.
It is necessary to strike the seat once to assure a
perfect seat. This may be done with a short section
of hard wood and a four-pound (1.8 kilogram)
hammer. The end of the wood block placed against
the valve seat should be large enough to cover the
outer sealing ring. One sharp blow should be
sufficient for proper seating. Additional hits may jar
the seat loose and could damage the seat. Check
the seat top surface to see that it has not been
damaged after the seat has been installed.
The wing guided valves can be removed with a puller
that uses a cam arrangement to pass through the
seat opening and engage one side of the seat
bottom. This type head is preferred since it is less
likely to damage the seat during the pulling
procedure.
The tapered seat valves can be removed with a
threaded puller head. This type puller head has
threads on the outside diameter that match the
threads cut into the inside diameter of the seat. A
hydraulic jack type puller can be used with this type
head.
WARNING
Pump must never be operated at speeds or
pressures exceeding the values shown on
the nameplate. Never operate pump below
50 RPM on intermittent service or 100 RPM
on continuous service without written
approval from Gardner Denver Inc. Failure
to observe this warning could result in
severe pump damage due to overloading
and/or lack of adequate lubrication.
DANGER
Wear eye protection when removing the
valve seat as metal chips could be
dislodged from the valve seat or valve
puller and fly up into your face.
DANGER
If a seat puller powered by a hydraulic jack
is used, be certain to chain or tie the jack
down as it will jump violently when the
valve seat lets go.
WARNING
Never attempt to install the valves as an assembly.
The valve could be damaged when a block and
hammer are used to strike the retainer to set the
seat