SANDPIPER MP07D User Manual

SERVICE AND OPERATING MANUAL

A WARREN RUPP PUMP BRAND

PLEASE NOTE!

The photos shown in this manual are for general instruction only. Your specific
model may not be shown. Always refer to the parts list and exploded view drawing
for your specific model when installing, disassembling or servicing your pump.

PRINCIPLE OF OPERATION

All Marathon pumps, including this Spill Containment model, operate on the
same basic principle. They are powered by compressed air which alternately
pressurizes the inner sides of the two diaphragm chambers while simultaneously
exhausting the opposite inner chambers causing the diaphragms, which are
connected by a shaft, to move endwise. Since air pressure is applied over the entire
surface of the diaphragm which is forcing liquid to be discharged by its other side,
the diaphragm is operating under a balanced condition during the discharge stroke.
This allows the unit to be operated at discharge heads over 200 feet (61 meters) of
water head.

Alternate pressurizing and exhausting of the diaphragm chamber is performed
by an externally mounted, pilot-operated, four way, spool type air distribution valve.
When the spool is at one end of the valve body, inlet air pressure is connected to one
diaphragm chamber and the other diaphragm chamber is connected to the exhaust.
When the spool is removed to the opposite end of the valve body, the porting of
chambers is reversed. The air distribution valve spool is moved from one end position
to the other in the valve body by means of an internal pilot valve which alternately
pressurizes the ends of the air distribution valve spool while simultaneously
exhausting the other ends. The pilot valve is positively shifted at each end of the
diaphragm stroke by the diaphragm plate’s coming in contact with the end of the pilot
valve spool and pushing it into position for shifting of the air distribution valve. The
chambers are manifolded together with a suction and discharge check valve for each
chamber to maintain flow in one direction through the pump.

This Marathon pump differs from other Marathons only in that it utilizes four
diaphragms instead of two, the two rod-connected diaphragms being the driver
diaphragms, and the other two (outermost) diaphragms being the actual pumping
diaphragms. Each driver diaphragm (of Neoprene or other elastomer), and the
pumping diaphragm (of Teflon), are separated by a chamber filled with liquid which
transmits the reciprocating motion of the driver diaphragm to the pumping diaphragm.
The Teflon pumping diaphragms, in turn, create the alternating suction and discharge
action to each outer diaphragm chamber. The outer diaphragms are the only ones in
contact with the liquid being pumped.

INSTALLATION PROCEDURES

Position the pump as close as possible to the source of the liquid to be pumped.
Avoid long or undersize suction lines and use the minimum number of fittings. High
vacuums reduce flow rate capability and shorten driver diaphragm service life.
Suction head is not recommended except where NPSH might so dictate.

For permanent installations involving rigid piping, install short flexible sections
of hose between the pump and piping. This reduces strains and permits easier
removal of the pump for service when required. At time of installation, inspect all

external gasketed fasteners for looseness caused by gasket creep. Tighten
loose fittings securely to prevent leakage.

FILLING OF DRIVER CHAMBERS WITH LIQUID

THE DRIVER CHAMBERS WILL BE FILLED WITH WATER AT THE FACTORY.

If you prefer to substitute another liquid, to prevent system contamination consult
the factory first to determine compatibility of the substitute with pump construction.

Follow the steps listed below to replace the liquid in the pump after disassembly
or liquid loss:

Model MP07D

Design Level 3

IMPORTANT

Read these instructions completely,
before installation and start-up. It is
the responsibility of the purchaser to
retain this manual for reference.
Failure to comply with the
recommendations stated in this
manual will damage the pump, and
void factory warranty.

WARNING

Take action to prevent static sparking.
Fire or explosion can result, especially
when handling flammable liquids. The
pump, piping, valves, containers or
other miscellaneous equipment must
be grounded.

BEFORE OPERATION

Before pump operation, all external
gasketed fasteners must be inspected
for looseness caused by gasket creep
after leaving the factory. Retorque
loose fasteners to insure against
leakage. Follow recommended
torques where called out. (A card is
attached to each new pump stating
this fact.)

CAUTION

This pump should not be applied in
pumping applications where the
driver liquid coming in contact with
the pumped liquid would create a
hazardous condition. This could
happen in case of a Teflon pumping
diaghragm failure since this
diaphragm normally separates the two
liquids. Also note that care must be
taken to guard against the operation
of this unit if it has been subjected to
freezing temperatures. Because of the
driver liquid used, possible
diaphragm failure may result.

WARREN RUPP, INC. A Unit of IDEX Corporation • P.O. Box 1568 • Mansfield, Ohio 44901-1568 USA • [phone] Fax [phone]

Model MP07D Design Level 3 Page 1 520-134-000 3/03

1. Filling is accomplished through the pipe plugs at the top of the liquid driver

chamber. Remove the plugs.

2. Remove the entire discharge manifold assembly exposing the ports in the

outer diaphragm chambers.

3. With 5-10 PSI of air pressure at inlet, lock the spool to one side with locking pin
(safety clip; item 61) (Fig. 1). You will fill the opposite side diaphragm from the
“Locked Area.”

4. Fill with 2500MI. (84.53 fl. oz.) by volume with the driver liquid. It is imperative
that the driver liquid chambers be filled with the correct amount of driver liquid as too
little or too much will cause premature diaphragm failure and erratic pumping.

5. After filling with the proper amount of liquid, if the liquid does not come to the
top of the fill hole, pressure should be applied to the Teflon diaphragm with a blunt
tool through the material flow port in the outer chamber until it does come to the top.
Relieving air pressure will relax diaphragms at this point.

6. When the driver fluid rises to the top of the fill plug hole, screw the boss plug,
with o-ring installed, into the chamber. (Do not overtighten.) (Fig. 2) Remember to
keep pressure on the Teflon diaphragm until the boss plug is tight to prevent air from
drawing back into the chamber.

7. Filling the opposite side is accomplished in the same manner as described.

AIR SUPPLY

Do not connect the unit to an air supply in excess of 125 PSI (8.61 bars). Install
a shutoff valve in the air supply line to permit removal of the unit for servicing. When
connecting an air supply of rigid piping, mount a section of flexible line to the pump
to eliminate piping strain. In permanent installations, an air line filter is
recommended.

A NOTE ABOUT AIR VALVE LUBRICATION

The Marathon pump’s pilot valve and main air valve assemblies are designed to
operate WITHOUT lubrication. This is the preferred mode of operation. There may
be instances of personal preference, or poor quality air supplies when lubrication of
the compressed air supply is required. The pump air system will operate with
properly lubricated compressed air supplies. Proper lubrication of the compressed
air supply would entail the use of an air line lubricator (available from Marathon) set
to deliver one drop of 10 wt., non-detergent oil for every 20 SCFM of air the pump
consumed at its point of operation. Consult the pump’s published Performance
Curve to determine this.

It is important to remember to inspect the sleeve and spool set routinely. It
should move back and forth freely. This is most important when the air supply is
lubricated. If a lubricator is used, oil accumulation will, over time, collect any debris
from the compressed air. This can prevent the pump from operating properly.

Water in the compressed air supply can create problems such as icing or
freezing of the exhaust air causing the pump to cycle erratically, or stop operating.
This can be addressed by using a point of use air dryer (available from Marathon) to
supplement a plant’s air drying equipment. This device will remove excess water
from the compressed air supply and alleviate the icing or freezing problem.

EXTERNALLY SERVICEABLE AIR
DISTRIBUTION SYSTEM

Please refer to the exploded view drawing and parts list in the Service Manual
supplied with your pump. If you need replacement or additional copies, contact your
local Marathon Distributor, or the Marathon factory Literature Department at the number
shown below. To receive the correct manual, you must specify the MODEL and TYPE
information found on the name plate of the pump.

MODELS WITH 1" SUCTION/DISCHARGE OR LARGER,
AND METAL CENTER SECTIONS:

The main air valve sleeve and spool set is located in the valve body mounted on the
pump with four hex head capscrews. The valve body assembly is removed from the
pump by removing these four hex head capscrews.

With the valve body assembly off the pump, access to the sleeve and spool set is
made by removing four hex head capscrews (each end) on the end caps of the valve
body assembly. With the end caps removed, slide the spool back and forth in the sleeve.
The spool is closely sized to the sleeve and must move freely to allow for proper pump
operation. An accumulation of oil, dirt or other contaminants from the pump’s air supply,

If the pump has been subjected to

CAUTION

freezing temperatures, do not operate
until the unit is completely thawed.

Fig. 1 Safety clip.

Fig. 2 Tighten the boss plug.

DANGER

Before doing any maintenance on
the pump, be certain all pressure is
completely vented from the pump,
suction, discharge, piping, and all
other openings and connections.
Be certain the air supply is locked
out or made non-operational, so that
it cannot be started while work
is being done on the pump. Be
certain that approved eye protection
and protective clothing are worn
at all times in the vicinity of the
pump. Failure to follow these
recommendations may result in
serious injury or death.

Model MP07D Design Level 3 Type 4 Page 2 520-134-000 3/03

or from a failed diaphragm, may prevent the spool from moving freely. This can cause
the spool to stick in a position that prevents the pump from operating. If this is the case,
the sleeve and spool set should be removed from the valve body for cleaning and further
inspection.

Remove the spool from the sleeve. Using an arbor press or bench vise (with an
improvised mandrel), press the sleeve from the valve body. Take care not to damage
the sleeve. At this point, inspect the o-rings on the sleeve for nicks, tears or abrasions.
Damage of this sort could happen during assembly or servicing. A sheared or cut
o-ring can allow the pump’s compressed air supply to leak or bypass within the air valve
assembly, causing the pump to leak compressed air from the pump air exhaust or not
cycle properly. This is most noticeable at pump dead head or high discharge pressure
conditions. Replace any of these o-rings as required or set up a routine, preventive
maintenance schedule to do so on a regular basis. This practice should include
cleaning the spool and sleeve components with a safety solvent or equivalent,
inspecting for signs of wear or damage, and replacing worn components.

To re-install the sleeve and spool set, lightly lubricate the o-rings on the sleeve with
an o-ring assembly lubricant or lightweight oil (such as 10 wt. air line lubricant). Press
the set into the valve body easily, without shearing the o-rings. Re-install one end cap,
gasket and bumper on the valve body. Using the arbor press or bench vise that was
used in disassembly, press the sleeve back into the valve body. You may have to clean
the surfaces of the valve body where the end caps mount. Material may remain from
the old gasket. Old material not cleaned from this area may cause air leakage after
reassembly. Take care that the bumper stays in place allowing the sleeve to press in
all the way. Re-install the spool, the opposite end cap, gasket and bumper on the valve
body. After inspecting and cleaning the gasket surfaces on the valve body and
intermediate, re-install the valve body on the pump using new gaskets. Tighten the four
hex head capscrews evenly and in an alternating cross pattern.

OPERATION

Your Marathon pump has been tested prior to shipment and is ready for use as
received. It is completely self-priming and no initial filling with fluid is required.

If the unit is to be totally submerged, the air exhaust must be piped above the
liquid level to prevent the liquid and foreign material from entering the air
distribution valve mechanism.

Open the inlet air valve at least one turn to allow sufficient cycling rate for the
pump to prime (30 to 60 cycles per minute). After pumping starts, adjust the inlet air
valve for the desired pumping capacity. When further opening of the inlet air valve
increases cycling rate without increasing the flow rate, the pump is being starved of
liquid due to suction limitations. Further opening of the air inlet valve will waste
compressed air. Set the inlet air valve for lowest cycling rate that does not decrease
flow rate for most efficient operation.

FREEZING OR ICING OF EXHAUST

Icing of the air exhaust can occur under certain conditions of temperature and
humidity on compressed air power equipment. When pump performance suffers
because of icing, use of an air dryer will solve the problem. Icing is more likely to
occur at high discharge pressures.

AIR EXHAUST

Marathon pumps can be submerged if the materials of construction are
compatible with the liquid and the exhaust is piped above the liquid level. (See
OPERATION, above.) Piping used for the exhaust should not be smaller than 1"
pipe size. Reduced pipe size can restrict the exhausted air and reduce pump
performance.

CHECK VALVE SERVICING:

Need for inspection or service is usually indicated by poor priming, unstable
cycling, reduced performance or the pump’s cycling but not pumping.

DIAPHRAGM SERVICING:

Driver Diaphragms

Drain the driver diaphragm chamber by removing the boss plug on the
underside of the driver chamber. Remove eight bolts securing the two manifolds to
the chambers. Remove eight bolts securing the diaphragm chamber. This permits
inspection of the Teflon diaphragm and the driver diaphragm. Loosen the plate

In the event of diaphragm rupture,

CAUTION

pumped material may enter the air end
of the pump, and be discharged into
the atmosphere. If pumping a product
which is hazardous or toxic, the air
exhaust must be piped to an
appropriate area for safe disposition.

CAUTION

Do not use a wrench on the
diaphragm rod. Flaws on the surface
may damage the bearings and seals.

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