General Pump SMH User manual

SMH
Owner’s Manual
• Installation
• Use
• Maintenance
General Pump is a
member of the
Interpump Group Ref 300893 Rev. B
04-22

GENERAL PUMP A member of the Interpump Group SMH SERIES
INDEX
1. INTRODUCTION ...............................................................Page 3
2. DESCRIPTION OF SYMBOLS ....................................................Page 3
3. SAFETY ......................................................................Page 4
3.1 General safety instructions ....................................................Page 4
3.2 High pressure unit safety requirements...........................................Page 4
3.3 Safety during operation ....................................................... Page 4
3.4 General procedures for using nozzles and lances ..................................Page 4
3.5 Safety during unit maintenance .................................................Page 5
4. PUMP IDENTIFICATION .........................................................Page 5
5. TECHNICAL CHARACTERISTICS .................................................Page 6
6. DIMENSIONS AND WEIGHT .....................................................Page 7
7. OPERATING INSTRUCTIONS ....................................................Page 7
7.1 Water temperature ...........................................................Page 7
7.2 Maximum flow and pressure rates...............................................Page 7
7.3 Minimum RPM ..............................................................Page 7
7.4 Vibration...................................................................Page 7
7.5 Recommended lubricant types and manufacturers .................................. Page 8
8. PORTS AND CONNECTIONS ....................................................Page 10
8.1 Linings/Nose Cones..........................................................Page 10
9. PUMP INSTALLATION ..........................................................Page 11
9.1 Installation .................................................................Page 11
9.2 Direction of rotation .......................................................... Page 12
9.3 Version Change and reduction gear positioning ....................................Page 12
9.4 Hydraulic connections ........................................................Page 13
9.5 Pump power supply ..........................................................Page 13
9.6 Inlet line ...................................................................Page 13
9.7 Filtration ...................................................................Page 14
9.8 Outlet line..................................................................Page 14
9.9 Internal diameter of hose ......................................................Page 15
9.10 V-belt transmission .........................................................Page 16
9.11 Transmission of power from the second PTO ..................................... Page 16
10. START UP AND OPERATION ....................................................Page 17
10.1 Preliminary inspections ......................................................Page 17
10.2 Starting up ................................................................Page 17
10.3 Cooling circuit seal packing ...................................................Page 18
11. PREVENTATIVE MAINTENANCE .................................................Page 18
12. PUMP STORAGE ..............................................................Page 19
12.1 Inactivity for lengthy periods ..................................................Page 19
12.2 Filling the pump with anti-corrosion emulsion or anti-freeze ..........................Page 19
12.3 Hoses....................................................................Page 19
13. PRECAUTIONS AGAINST FREEZING..............................................Page 19
14. WARRANTY TERMS............................................................Page 19
15 TROUBLESHOOTING...........................................................Page 20
16. EXPLODED VIEWS AND PARTS..................................................Page 21
17. REPAIR KITS / TORQUE SPECS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 23
18. MAINTENANCE LOG ...........................................................Page 24
Page 2
Ref 300893 Rev. B
04-22

Page 3
2. SYMBOL DESCRIPTIONS
Warning
Potential Danger
Danger
High Voltage
Danger
Wear protective mask
Danger
Wear goggles
Danger
Wear protective gloves
Danger
Wear protective boots
Read carefully and understand
the manual before operating
the pump
1. INTRODUCTION
This manual describes the use and maintenance instructions of the SMH pump, and should be carefully read and
understood before using the pump.
Correct use and adequate maintenance will guarantee the pumps trouble-free operation for a long time. General Pump
declines any responsibility for damage caused by misuse or the non-observance of the instructions indicated in this
manual.
Upon receiving the pump, check that it is complete and in perfect condition. Should anything be found out of order, please
contact us before installing and starting the pump.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 4
3. SAFETY
3.1 General Safety Indications
Improper use of pumps and high pressure systems, and/or failure to observe the installation and maintenance
instructions may cause serious injury to people and/or damage to property. Anyone assembling or using high pressure
systems must possess the necessary competence to do so, should be aware of the characteristics of the components
assembled/used, and must take all precautions necessary to ensure maximum safety in any operating condition. In the
interest of safety, both for the Installer and the Operator, no reasonably applicable precaution should be omitted.
3.2 High pressure unit safety requirements
1. The pressure line must always be equipped with a safety valve.
2. High pressure system components, in particular for those units working outside, must be adequately protected
against rain, frost and heat.
3. The electrical control system must be adequately protected from water spray, and must comply with the specific
regulations in force.
4. High pressure hoses must be properly sized for maximum operating pressure of the system and always and only
used within the operating pressure range specified by the hose manufacturer. The same rules should be observed
for all other auxiliary systems affected by high pressure.
5. The ends of high pressure hoses must be sheathed and secured to a solid structure to prevent dangerous
whiplash in case of bursting or broken connections.
6. Appropriate safety guards must be provided for the pump transmission systems (couplings, pulleys and belts,
auxiliary drives).
3.3 Safety During Operation
The working area of a high pressure system must be clearly marked. Access must be prohibited to unauthorized
personnel and, wherever possible, the area should restricted or fenced. The personnel authorized to access this area
should first be trained, and informed about the risks that may arise from failures or malfunctions of the high pressure
unit.
Before starting the unit, the operator must verify that:
1. The high pressure system is properly fed by a minimum pressure of 75-100 PSI (5-7 Bar), metered in the head
flange.
2. The pump intake filters are perfectly clean; we recommend the use of a device that indicates the filters clogging
level.
3. Electrical parts are adequately protected and in perfect condition.
4. The high pressure hoses do not show evident signs of abrasion, and that fittings are in perfect shape.
5. During use pump may get hot. Avoid contact with hot parts.
Any fault or reasonable doubt that may arise before or during operation should be promptly reported and verified by
competent personnel. In these cases, pressure should immediately be released and the high pressure system stopped.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 5
Note: appropriate clothing will effectively protect against water spray, but it may not offer adequate protection against
the direct impact of water jets or sprays from a close distance. Some circumstances may require further protection.
3. It is generally best to organize personnel into teams of at least two people capable of giving mutual and immediate
assistance in case of necessity and of taking turns during long and demanding operation.
4. Access to the work area that is within the water jets’ range must be absolutely prohibited to and free from objects
that, inadvertently under a pressure jet, can be damaged and or create dangerous situations.
5. The water jet must only and always be directed in the direction of the work area, including during testing or
preliminary tests or checks..
6. The Operator must always pay attention to the trajectory of the debris removed by the water jet. If necessary,
suitable guards must be provided by the Operator to protect anything that may be accentually exposed.
7. The Operator should not be distracted for any reason during operation. Workers needing to access the operating
area must wait for the Operator to stop work, and then immediately make their presence known.
8. For safety reasons, it is important that each member of the team is fully aware of the intentions and actions of
other team members in order to avoid dangerous misunderstandings.
9. The high pressure system must not be started up and run under pressure without all team members in position
and without the Operator having already directed his/her lance toward the work area.
3.5 Safety During System Maintenance
1. The pressure system maintenance must be carried out in the time intervals set by the manufacturer who is
responsible for the whole group according to law.
2. Maintenance should always be carried out by trained and authorized personnel.
3. Assembly and disassembly of the pump and its various components must be performed exclusively by authorized
personnel, using appropriate equipment in order to avoid damage to components and connections.
4. Always use original spare parts to ensure total reliability and safety.
4. PUMP IDENTIFICATION
Each pump has a specific label which contains:
Pump model and version
Serial Number
Maximum RPM
Power - Hp-kW
Pressure - PSI
Flow Rate - GPM
Pump model, version and serial number must always
be specified when ordering spare parts.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES
3.4 General Procedures For Using Lances/Nozzles
1. The Operator must always place his own and other worker’s safety before any other interest; his and should always
be governed by good sense and responsibility.
2. The Operator must always wear a helmet with a protective visor, waterproof clothing, and appropriate boots capable
of guaranteeing grip on wet pavement.

Page 6
5. TECHNICAL FEATURES
MODEL RPM FLOW RATE PRESSURE POWER
GPM l/min PSI Bar Hp kW
SMH14
800 6.9 26 21750 1500 101 74
1500 6.9 26 21750 1500 101 74
1800 6.9 26 21750 1500 101 74
2200 6.9 26 21750 1500 101 74
SMH16
800 9.0 34 17400 1200 106 78
1500 9.0 34 17400 1200 106 78
1800 9.0 34 17400 1200 106 78
2200 9.0 34 17400 1200 106 78
SMH18
800 11.4 43 13050 900 101 74
1500 11.4 43 13050 900 101 74
1800 11.4 43 13050 900 101 74
2200 11.4 43 13050 900 101 74
SMH20
800 14.0 53 10875 750 103 76
1500 14.0 53 10875 750 103 76
1800 14.0 53 10875 750 103 76
2200 14.0 53 10875 750 103 76
SMH22
800 16.9 64 8700 600 100 73.5
1500 16.9 64 8700 600 100 73.5
1800 16.9 64 8700 600 100 73.5
2200 17.2 65 8700 600 101 74
SMH24
800 20.1 76 7250 500 99 73
1500 20.1 76 7250 500 99 73
1800 20.1 76 7250 500 99 73
2200 20.3 77 7250 500 100 73.5
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 7
6. DIMENSIONS AND WEIGHT
fig. 2
Weight: 573 Lbs./260 Kg.
For dimensions and weight, please refer to fig. 2.
7. OPERATING INSTRUCTIONS
The SMH pump was designed to operate with filtered water (see paragraph 9.7) and at maximum tempera-
ture of 104oF (40oC).
Other fluids may be used only upon the approval of The Customer Service Department.
7.1 Water Temperature
The max water temperature is 85°F (30°C).
7.2 Max Flow Rate and Pressure Values
The performance values indicated in the catalog refer to the maximum performance of the pump. Regardless of the power
used, pressure and maximum RPM values indicated on the plate may not be exceeded unless expressly authorized by the
Customer Service Department.
7.3 Lowest RPM
The minimum speed allowed for these types of pumps is 300 rpm; any rpm other than mentioned and shown in the perfor-
mance table (see chapter 5) must be expressly and formally authorized by the Customer Service Department.
7.4 Vibration
The detection of vibration shall be carried out only with the pump set up on the plant and at the performance declared by
the customer. Values must be in accordance with regulations.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

7.5 Recommended Lubricant Oil Types & Manufacturers
The pump is delivered with lubricant oil compliant with room temperatures ranging between 32°and 89.6°F (0°and
30° C). Some recommended lubricant types are indicated in the table below; these lubricants are treated with additives
in order to increase corrosion protection and resistance to fatigue. As an alternative, Automotive SAE 85W-90 gearing
lubricants may also be used.
BRAND TYPE
GENERAL PUMP SERIES 220
ARAL Aral Degol BG220
BP ENERGOL HLP 220
CASTROL
Hyspin VG 220, Magna 220
ELF
POLYTELIS 220
ESSO NUTO 220
FINA Cirkan 220
FUCHS RENOLIN 220
MOBIL DTE OIL BB
SHELL TELLUS C 220
TEXACO RANDO HD 220
TOTAL CORTIS 220
Check the oil level with the oil level lights located on the sides (1, fig. 3). If necessary, top off via the
oil plug (3, fig. 3).
To correctly check the oil level the pump must be at ambient temperature. To change the oil the pump
must be at operating temperature, and is done by removing the plug (2, fig. 3).
Checking and changing the oil must be done as shown in Chapter 11. The quantity necessary is 287
oz. (8.5 liters) for pumps with a reduction unit and 253 oz. (7.5 liters) for pumps with no reduction unit.
Page 8
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 9
In any case, oil must be changed at least once a year since it may deteriorate by oxidation.
For room temperatures other than between 32°- 86°F (0°- 30°C), follow the indications contained in the diagram
below, keeping in mind that the oil must have a minimum viscosity of 180 cSt.
VISCOSITY/ROOM TEMPERATURE DIAGRAM
Exhausted oil must be collected in an appropriate container and disposed of in appropriate
locations. Do not under any circumstances discard it into the environment.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 10
8. PORTS AND CONNECTIONS
SM Series pumps are equipped with (see fig. 4):
1. 2 inlet ports “IN”, 1-1/2” Gas
The line can be connected to either of the two inlet ports; the ones not being used must be hermetically sealed.
2. 2 outlet ports “OUT”, Ø 13mm
3. 2 service ports, 1/2” Gas. These can be used for the pressure gauge
4. 1 drain port “DRAIN” supplied with a 90oadjustable quick coupling for polyamory hose with Ø 12mm. These allow
drainage recovery of the seal pack cooling circuit and must be connected to the discharge, making sure that there
is no back pressure.
8.1 Linings/Nose Cones
SMH pumps are provided with 4 steel tapered linings, for use in the corresponding outlet ports of the pump (see fig. 5)
or in the optional connection flanges, to ensure the connection seal. While the seat of the pump’s outlet port is already
machined to accept the tapered lining, if it is necessary to make the connection for the outlet connection or the closing
plug, these must be specifically machined as shown in fig. 5a.
At every disassembly, the tapered linings must be replaced.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 11
The brackets are sized solely for pump lifting and therefore are absolutely not permitted for use of
additional loads.
9. PUMP INSTALLATION
9.1 Installation
The pump must be installed in a horizontal position using the M 16x1.5 threaded support feet. Tighten the screws with a
torque of 148 ft. lbs. (200 Nm). The base must be perfectly flat and rigid enough as not to allow bending or misalignment
on the pump coupling and axis/transmission due to torque transmitted during operation.
Two lifting eyebolts are mounted on the pump for easy installation, as per the figure below.
Ref 300893 Rev. B
04-22
Replace the oil filling hole closing service plug positioned on the rear casing cover with the plug
with oil dipstick. Check the correct quantity of oil. The dipstick must always be reachable, even when
the unit is assembled.
The pump shaft (PTO) should not be rigidly connected to the propulsor unit
The following typed of transmissions are recommended:
• Flexible joint
• Cardan-shaft (comply with manufacturer’s Max. recommended working angles)
• Belts. For proper application consult with our Customer Service Department
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 12
Ref 300893 Rev. B
04-22
9.2 Direction of rotation
The PTO rotation is indicated by an arrow located on the reduction gear cover. From a position facing the pump head,
the rotation direction will be as in fig. 6.
9.3 Version change and reduction gear positioning
The pump version is defined as right when: observing the pump facing the head side, the crankshaft is on the right side.
The pump version is defined as left when: observing the pump facing the head side, the crankshaft is on the left side.
The version can only be modified by trained and authorized personnel and carefully following the
instructions below:
1. Separate the hydraulic part from the mechanical part as indicated in Chapter 2, section 2.2.1 of the repair
manual.
2. Turn the mechanical part 180°and reposition the rear casing cover in such a way that the oil dipstick is turned
upward. Reposition the lifting bracket and relative hole closing plugs in the upper part of the casing. Invert
the two inspection covers, ensuring that the open one is positioned lower. Finally, properly reposition the
specification label in its housing on the casing.
Make sure that the lower inspection cover draining holes are open
3. Join the hydraulic part to the mechanical part as indicated in Chapter 2, section 2.2.2 of the repair manual.
It is also possible to place the reduction gear in 5 different positions as per fig. 7.
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 13
9.4 Hydraulic Connections
To isolate the plant from the vibrations produced by the pump, we recommend building the first section of hose
adjacent to the pump (for both intake and outlet) with flixible hose. The solidity of the intake section must be enough to
prevent deformation caused by the depression produced by the pump.
9.5 Pump Supply
SMH pumps require a positive water head (NPSHr) of between 75-100 PSI (5-7 Bar) at the pump head entrance. The
booster supply pump must have a flow rate at least double that of the rated flow rate of the plunger pump, and a
minimum pressure of 75 PSI (5 bar). These supply conditions must be respected for any and all working regimes. The
booster pump must be run independent of the plunger pump.
The booster pump must always be started before the plunger pump. We recommend installing a
pressure regulator on the supply line downstream of the filters, to protect the pump.
9.6 Suction Line
For the pump’s correct operation, the suction line must have the following characteristics:
1. Minimum internal diameter as indicated in the diagram in paragraph 9.8 and in any case equal or greater
than the pump head’s value. Along the duct, avoid localized diameter reductions that may cause pressure
drops with subsequent cavitation. Absolutely avoid 90oelbows, connections with other hoses, bottlenecks,
counter-slopes, upside down “U” shaped curves, “T” connections.
2. With a layout that is set in such a way to prevent cavitation.
3. It should be perfectly airtight, and built in a way that guarantees perfect sealing over time.
4. Avoid pump emptying when stopping (even partial emptying).
5. Do not use hydraulic fittings, 3 or 4 way fittings, adapters, etc., since they may hinder the pump’s
performance.
6. Do not install Venturi tubes or injectors for detergent intake.
7. Avoid the use of standing valves, check valves, or any other type of one-way valves.
8. Do not connect the by-pass line from the valve directly to the pump suction line.
9. Provide appropriate baffle plates inside the tank in order to avoid water flows coming from both the by-pass
and feeding lines may create turbulence near the tank’s outlet port.
10. Make sure that the suction line is perfectly clean inside before connecting it to the pump.
11. The pressure gauge for checking booster pressure must be installed near the plunger pump’s outlet port,
and always downstream from the filters.
Ref 300893 Rev. B
04-22
The reducer’s position may be changed only by specialized and authorized personnel by carefully
following the instructions in the repair manual.
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 14
9.7 Filtration
The level of filtration permitted for this series of pumps must be maximum 20 µm (micron). Normally this is obtained by a
battery of at least three filters, positioned as shown in fig. 8.
The filters must be installed as close as possible to the pump. They must be easily accessible for inspection and must
have the following specifications:
Filter number 1: 250 µm
Filter number 3: 100 µm
Filter number 4: 20 µm
In order to guarantee correct pump operation, it is important to plan periodical cleaning of the filter
depending on actual pump usage, water quality and actual clogging conditions.
To guarantee the supply pressure required (see 9.5) install a pressure regulator.
9.8 Outlet Line
To obtain a correct outlet line, please comply with the following installation instructions:
1. The internal diameter of the pump must allow to guarantee correct fluid speed; see digram in paragraph 9.9
2. The first section of the hose connected to the pump must be flexible in order to isolate pump vibrations
from the rest of the system.
3. Use high pressure hoses and fittings that guarantee wide safety margins in any working condition.
4. Install a safety valve on the outlet line.
5. Use pressure gauges suitable to withstand the pulsating loads typical of plunger pumps.
6. In the design phase, take into proper account the pressure drop along the line, since this causes a reduction in
usage pressure with respect to the value measured at the pump.
7. If the pump pulsations are harmful for particular applications, install an appropriately sized pulsation dampener on
the outlet line.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 15
9.9 Internal Diameter of the Hose Line
To determine the internal diameter of the hose, please refer to the following diagram.
Inlet Hose
With a flow rate of ~21 GPM (80 l/mn) and water speed of 0.5 m/sec. The diagram line that connects the two scales
intersects the central scale, indicating the diameters, at a value of ~ 2.3 inch (58 mm).
Outlet Hose
With a flow rate of ~21 GPM (80 l/mn) and water speed of 5.5 m/sec. The diagram line that connects the two scales
intersects the central scale, indicating the diameters at a value of ~ .71 inch (18 mm).
Optimal speed to be obtained with the booster pump:
• Suction: ≤ 0.5 m/sec.
• Delivery: ≤ 5.5 m/sec.
The diagram does not take into account the hose and valve resistance, the pressure drop due to the pipe length,
the viscosity and the temperature of the pumped fluid. If necessary, contact our Customer Service Department.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 16
9.10 V-belt Transmission
As indicated in point 9.1, the pump can be controlled by a v-belt system only in exceptional cases. For proper layout
sizing, consult our Customer Service Department.
9.11 Transmission of power from the second crankshaft
SM series pumps can, upon request, be supplied with an auxiliary power outlet on the opposite side of the activation.
Transmission can be carried out:
• By means of the V-belts
• By means of the joint
By means of the V-belt, with drawable max torque is 111 ft. lbs (150 Nm) corresponding to 17 HP (12.5 Kw) at 800
RPM.
By means of the joint, with drawable max torque is 162 ft. lbs. (220 Nm) corresponding to 25 HP (18.4 Kw) at 800 RPM.
With transmission by means of the joint, pay particular attention to perfect alignment so that no
transverse forces are generated on the pump shaft.
For applications differing from those specified above, contact our Customer Service Department.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 17
10. START-UP AND OPERATION
10.1 Preliminary Inspections
Before Start-up Be sure that:
The inlet line is connected and up to pressure (see Chapter 9) the pump must NEVER run dry.
1. The inlet line must be perfectly airtight.
2. All the On-Off valves between the pump and the feeding source are completely open. The outlet line must
discharge freely in order to allow the air in the pump to be expulsed easily, thus facilitating pump priming.
3. All fittings and connections must be correctly tightened.
4. Coupling tolerances on the pump/transmission axis (half-joint misalignment, Cardan inclination, belt
tightening, etc.) must remain within the limits indicated by the transmission Manufacturer.
5. The pump’s oil level must be verified using the correct dipsticks (position 1, fig 9).
In case the pump has not run for a long period of time, recover the correct operation of the suction valves
by opening the three valve-lifting devices (see fig. 9). Be sure to reclose the valves before the pump
start-up.
10.2 Start-up
1. When starting the pump for the first time, check for the correct direction of rotation.
2. The pump must be started off-load.
3. Verify correct feeding pressure.
4. During operation, check that the rotating speed does not exceed the rated value.
5. Before putting the pump under pressure let it run for at least 3 minutes.
6. Before stopping the pump, release the pressure by acting on the adjustment valve or on any discharging device.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 18
11. PREVENTIVE MAINTENANCE
PREVENTIVE MAINTENANCE
EVERY 500 HOURS EVERY 1000 HOURS
Check oil level Change oil
Check / Replace:*
• Valves
• Valve seats
• Valve springs
• Valve guides
Check / Replace:
• H.P packings
• L.P. packings
To guarantee pump reliability and efficiency, comply with the maintenance intervals as indicated in the table below.
* For replacement follow instructions contained in the repair manual.
10.3 Seal Pack Cooling Circuit
During operation, some water from the cooling circuit seal packings will be discharged from port 1 (fig. 10). The drainage
from this circuit must be redirected to the inlet line upstream of the booster pump (fig. 10) or to the collection tank.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

Page 19
12. PUMP STORAGE
12.2 Filling the Pump With An Anti-Corrosion Emulsion or Antifreeze By Using An External Diaphragm Pump
As In The Layout Shown in Paragraph 9.6.
a) Close the filter draining, if open.
b) Be sure that the connecting hose is clean, spread with grease and connect it to the high pressure outlet port.
c) Fit a suction hose to the membrane pump. Open the pump suction connection and fit hose between it and the
membrane pump.
d) Fill the container with the solution/emulsion.
e) Put the free extremities of the suction line and the high pressure outlet hose inside the container.
f) Start up the diaphragm pump.
g) Pump the emulsion until it comes out of the high pressure hose.
h) Continue pumping for at least another minute; if needed, the emulsion can be reinforced by adding, for example,
Shell Donax
i) Stop the pump, remove the hose from the suction connection and close it with a plug.
j) Remove the hose from the high pressure outlet port. Clean, grease and plug both connections and the
hoses.
12.3 Hoses
a) Before greasing and protecting the hoses according to the previously described procedure, dry the connections
using compressed air.
b) Cover with polyethylene.
c) Do not wrap them too tightly; be sure there is no bending.
13. PRECAUTIONS AGAINST FREEZING
In areas and periods of the year where there is risk of freezing, follow the instructions indicated in Chapter 12
(see paragraph 12.2).
In the presence of ice, in no case must the pump be started until the entire circuit has been completely
thawed out; not complying with this indication may cause serious damage to the pump.
14. WARRANTY TERMS
The pump is guaranteed for a period of 5 years from the delivery date, with the exception of parts subject to wear. In
any case, please refer to the contract terms for other warranty conditions. The warranty is void if:
a) The pump has been used for purposes that differ from that agreed.
b) The pump has been fit with an electric or diesel engine with performance greater than that indicated in the table.
c) The required safety devices were un-adjusted or disconnected.
d) The pump was used with accessories or spare parts not supplied by General Pump.
e) Damage was caused by:
1) improper use
2) the non-observance of maintenance instructions
3) use not compliant with operating instructions
4) insufficient flow rate
5) faulty installation
6) incorrect positioning or sizing of the hoses
7) non-authorized design changes
8) cavitation
12.1 Inactivity for Lengthly Periods
If the pump is started for the first time after a long period of inactivity, before putting it into operation check the
oil level, inspect the valves as indicated in Chapter 10, and then follow the prescribed startup procedures.
Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES

15. TROUBLESHOOTING
The pump does not produce any noise at start-up:
• The pump is not primed and is running dry
• There is no water in the inlet line
• The valves are blocked
• The delivery line is closed and does not allow the air in the pump to be discharged
The pump pulses irregularly (knocking):
• Air suction
• Insufficient feeding
• Bends, elbows, fittings along the suction line obstruct the fluid’s passage
• The inlet filter is dirty or too small
• The booster pump, where provided, supplies insufficient pressure or flow rate
• The pump is not primed due to insufficient head or the delivery line is closed during priming
• The pump is not primed due to valve seizing
• Worn valves
• Worn pressure packings
• Incorrect operation of the pressure adjustment valve
• Transmission problems
The pump does not deliver the rated flow / is noisy:
• Insufficient feeding (see the causes listed above)
• RPM are less than the rated flow
• Excessive amount of water by-passed by the pressure adjustment valve
• Worn valves
• Leakage from the pressure packings
• Cavitation due to:
1) Wrong sizing of the suction hose/
undersized diameters
2) Insufficient flow rate
3) High water temperature
Insufficient pump pressure:
• The nozzle (or has become) too large
• Insufficient RPM
• Leakage from the pressure packings
• Incorrect operation of the pressure adjustment valve
• Worn valves
Overheated pump:
• The pump is overloaded (pressure or RPM exceed the rated values)
• Oil level is too low, or the oil is not of a suitable type, indicated in Chapter 7 (see paragraph 7.4)
• Incorrect alignment of the joint or pulleys
• Excessive inclination of the pump during operation
Pump vibrations or knocking:
• Air suction
• Incorrect operation of the pressure adjustment valve
• Valve malfunction
• Irregular drive transmission motion
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Ref 300893 Rev. B
04-22
GENERAL PUMP A member of the Interpump Group SMH SERIES