Waterous CX Series User manual

All content in this instruction is property of the Waterous Company. Instructions subject to change without notice.All content in this instruction is property of the Waterous Company. Instructions subject to change without notice.All content in this instruction is property of the Waterous Company. Instructions subject to change without notice.
Overhaul Instructions
CX Series Fire Pumps Section
4209
Form No.
F−1031 Issue Date Rev. Date 01/03/0701/83
Waterous Company 125 Hardman Avenue South, South St. Paul, Minnesota 55075 USA (651) 450−5000
Instructions subject to change without notice.
Table of Contents
Introduction 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Overhaul Information 1. . . . . . . . . . . .
Tools and Equipment 1. . . . . . . . . . . . . . . . . . . . . .
Preliminary Testing 1. . . . . . . . . . . . . . . . . . . . . . .
Cleaning 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pump Bodies and Impellers 1. . . . . . . . . . . . . . . .
Bearings, Gaskets, Seals and O−rings 1. . . . . . .
Impeller Shafts 1. . . . . . . . . . . . . . . . . . . . . . . . . . .
Installing Ball Bearings 2. . . . . . . . . . . . . . . . . . . .
Installing Body Gaskets 2. . . . . . . . . . . . . . . . . . .
General Description 2. . . . . . . . . . . . . . . . . . . . .
Disassembly 2. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 3. . . . . . . . . . . . . . . . . . .
Mechanical Seal 3. . . . . . . . . . . . . . . . . . . . . . . . . .
Impellers 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installing Undersize Wear Rings 3. . . . . . . . . . . .
Reassembly 4. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mechanical Seal 4. . . . . . . . . . . . . . . . . . . . . . . . . .
Packing 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Packing Removal 5. . . . . . . . . . . . . . . . . . . . . . . . .
Packing Installation 5. . . . . . . . . . . . . . . . . . . . . . .
Final Assembly 6. . . . . . . . . . . . . . . . . . . . . . . . . . .
Packing Adjustment 6. . . . . . . . . . . . . . . . . . . . . . .
Vacuum Test 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Testing 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hydrostatic Testing 7. . . . . . . . . . . . . . . . . . . . . . .
Operational Testing 7. . . . . . . . . . . . . . . . . . . . . . .
Illustrations
1. Mechanical Seal Lubrication Application 4. . . . .
2. Packing Removal Tool 5. . . . . . . . . . . . . . . . . . . .
3. Packing Gland Tightening 6. . . . . . . . . . . . . . . . .
CX Series
Overhaul

F−1031, Section 4209 Page 1 of 7
Rev: 01/03/07
Introduction
This section contains overhaul instructions for Waterous CX Series centrif-
ugal fire pumps. Since several types of transmissions are used with the
CX Series pumps, the transmissions are covered in separate sections be-
ginning with number 4300.
Note that this instruction is written to cover several variations of the CX
Series pumps, not all steps will apply to any one pump.
Also refer to the Service Parts List (SPL documents) furnished with your
pump to aid in further part identification and repair parts ordering.
General Overhaul Information
Tools and Equipment
The following tools and equipment are needed to overhaul a pump:
1. Usual automotive mechanic’s hand tools.
2. An arbor press for assembling or disassembling components.
3. An engine lathe for turning impeller hubs.
4. A suitable hoist and slings.
5. Torque capability up to 325 lb−ft.
While no special tools and equipment are required, a few special items are
illustrated or described so the mechanic can make them or they are avail-
able from the apparatus manufacturer or the Waterous Company. These
special items are not absolutely necessary, but they will make the me-
chanic’s work much easier.
Preliminary Testing
Before disassembling a pump, test it thoroughly, if possible, and record the
results. A comparison of this test with periodic tests recommended in form
F−1031, Section 1000 can often reveal specific pump troubles. Excessive
speed, for instance, indicates that impellers and/or wear rings are probably
worn.
Cleaning
The continued satisfactory operation of a pump depends to a great extent
upon the cleanliness of its internal parts. Sand, dirt or other abrasive mate-
rial will wear bearings, gears and related parts. Before disassembling a
pump for repairs, be sure to clean its exterior. Make sure the working
space, benches and tools are clean. Use only clean, lint−free cloths to
wipe off components. Before reassembling a pump or its components, be
sure to clean them thoroughly.
Pump Bodies and Impellers
Flush out these components and related parts with clean water. Use a stiff
brush to remove loose scale, caked sediment, etc. Be sure to remove all
traces of old gaskets. Examine pump bodies, covers, adapters and fittings
for cracks, severe corrosion or other damage. Almost all damage to these
parts results from improper use or maintenance, or from freezing. Replace
defective parts.
Bearings, Gaskets, Seals and O−rings
Parts of this nature are frequently damaged during removal or disassemb-
ly. In addition, they sometimes deteriorate or lose their effectiveness be-
cause of age or misuse. Replacing these parts whenever overhauling a
pump is a good policy.
Impeller Shafts
Examine shaft for severe scratches, grooves or corrosion −especially un-
der packing or mechanical seals. If scratches are not severe, and are not
under packing and seals, clean them with a fine−cut file. Grooves under
the packing are usually permissible if they are not sharp or too deep. Even
slight longitudinal scratches will cause leaks and should be removed.

F−1031, Section 4209 Page 2 of 7
Rev: 01/03/07
Installing Ball Bearings
Most Waterous pumps are designed so that ball bearings fit tightly on their
shafts and have relatively loose fits in the bearing housings. When mount-
ing these bearings on shafts, always apply force to the inner races. When
bearings have a tight fit in the housings, and a heavy force is necessary to
install them, be sure to apply force only to the outer bearing races. For
either type of fit, applying force to the wrong bearing race may damage the
balls and race.
Installing Body Gaskets
To provide added sealing for gaskets between body halves, or between
bodies and intake adapters, coat both sides of these gaskets with a suit-
able sealant. A compound such as Permatex Super 300 is recommended
for this application. Be sure all traces of previous gaskets and sealant are
removed before installing new gaskets.
General Description
The CX series pumps are single stage centrifugal pumps. The combination
of single−stage design and vertically−split volute and pump transmission pro-
vide a simple to operate, easy to maintain pump. The use of heavy duty
gears, bearings and shafts provides longer, more trouble−free service and a
high reserve capacity. CX pumps are available with five transmission op-
tions, most providing pump−and−roll performance, in addition to its unique
mounting. The pump may be driven from engine crankshaft (front mounted),
power take−off driven, or direct engine driven (bellhousing mounted). Using
the “KC”style transmission, the CX provides easy access to water supply
when drafting and in hydrant operation. In addition, front mounted pumps
allow easy maintenance and repair.
Disassembly
A CX Series pump may be disassembled in several ways, depending on
the type of transmission used, the piping arrangement and similar factors.
The following instructions offer one of several means of removing and dis-
assembling a CX pump.
1. Disconnect drain lines, electrical wiring and similar connections to pump
and transmission.
2. Drain lubricant from transmission.
3. Disconnect propeller or drive shaft(s) from transmission.
4. Remove hex hd bolts (B5) and lock washers (B6) attaching suction
adapter (B7) to volute body (B3). Separate the adapter from the body and
replace O−ring (B8).
NOTE: On pumps with F, K or T transmissions, separating pump
head with transmission attached from the volute body might be
easier than the separation described below, space permitting.
5. Remove impeller nut (S13) and with a puller, remove impeller (S10). Also
remove key (S12). (Three puller holes in impeller have 1/4−20 NC thread.)
6. Packing: Loosen unbalanced nuts (S4) and remove packing gland (S6),
if used.
Mechanical Seal: Lubricate impeller shaft & slide bellows assembly
from impeller shaft. Seal can also be removed when removing head
(B2) from pump transmission. Remove stationary ring from pump
head.
7. Remove hex hd bolts (B5) and lock washer (B6) attaching volute body
(B3) to head (B2). Slide volute body carefully from head.
8. Remove hex hd bolts attaching head (B2) to pump transmission. Slide
head (B2) from impeller shaft.
9. Removing impeller shaft from transmission is not necessary unless it is
damaged. If impeller shaft removal is necessary, see the appropriate
transmission overhaul instructions.

F−1031, Section 4209 Page 3 of 7
Rev: 01/03/07
Inspection and Repair
Mechanical Seal
If a pump has a mechanical seal, installing a new seal during reassembly is
required. Check impeller shaft (S1) for damage. Make sure the shaft end and the edges of the keyway are free of burrs which will damage seal com- ponents during reassembly.
Impellers
Check impeller hubs and wear rings for deep grooves or scratches. Position
each wear ring on impeller hub on which it was used, hold wear ring firmly
against one side of hub and measure total clearance on opposite side (orig-
inal) factory clearance is from 0.008 to 0.012 in.). If clearance exceeds
0.020 in., then turn impeller hubs and install undersize wear rings as di-
rected below. If replacing an impeller is necessary, be sure to install new,
standard size wear rings. Examine lock nut and key for corrosion and other
damage and replace if condition is doubtful.
Installing Undersize Wear Rings
If inspection shows that the wear ring clearances are excessive or the impel-
ler hubs are scored or grooved, turn the impeller hub on a lathe to an accept-
able dimension at which they will clean up and install undersize wear rings
during reassembly. These repair rings are available 0.025, 0.050 or 0.075 in.
undersize.
Table 1 shows the original hub dimensions for each impeller and the rework
dimensions for each degree of undersize.
Table 1. Impeller and Wear Ring Repair Dimensions
Impeller Number Original HUB Diameter Original Wear Ring Number Reworked HUB Diameter New Wear Ring Number
71830/71831 6.375/6.373 6.350/6.345 62298−25/62299−25
71830−T/71831−T6.375 Max. 62298/62299 6.325/6.320
6.300/6.295 62298−50/62299−50 62298−75/62299−75
71888/71896 6.750/6.748 6.725/6.720 62420−25
71888−T/71896−T6.750 Max. 62420 6.700/6.695
6.675/6.670 62420−50 62420−75

F−1031, Section 4209 Page 4 of 7
Rev: 01/03/07
Reassembly
Reassembly is essentially the reverse of disassembly. If undersize wear rings are required, install them at this time. If a new impeller is needed, also install
new standard size wear rings for it. Refer to the following instructions on repacking pump or replacing mechanical seal.
Mechanical Seal
CAUTION
The mechanical seal primary and stationary rings are made of brittle ma-
terial. The material can be cracked or chipped. Extra care must be taken
when handling these rings.
NOTE: If Waterous Mechanical Seal Lubricant part no. 52608 is not
available, P80 rubber lubricant, straight dish soap or glycerin may be
substituted.
1. Apply a light coating of seal lubricant to the O−ring on the stationary
seal ring of the mechanical seal.
Note: To protect the rubber bellows of the mechanical seal, place
a piece of masking tape over the keyway on the impeller shaft,
making sure that the tape is able to be removed after bellows has
passed over the keyway.
2. Slip the ring over the end of the impeller shaft, with the finish lapped
face of the ring facing up (the opposite side of a new seal ring has a
mark on it). Slide it along the shaft and push it into and seat it in the
bore in the pump head. If it can not be pushed in by hand it may be
tapped into place by use of a block of wood between the ring and a
hammer.
3. Wipe the face of the previously installed stationary ring of the mechan-
ical seal with a clean lint free cloth or tissue paper and denatured alco-
hol.
4. Wipe a few drops of seal lubricant on the inside of the bellows of the
mechanical seal and wipe the face of the carbon ring with a lint free
cloth or tissue paper and denatured alcohol. Liberally coat impeller
shaft with seal lubricant. Slide the seal onto the shaft until the carbon
ring contacts the stationary seal ring. Install spring assembly.
5. Slide impeller on the shaft. The mechanical seal is held in place by
notches in the impeller. Continue pump assembly.
IL1024
Figure 1. Mechanical Seal Lubrication Application
If lubricant should get on face of seal ring, wipe it
clean with soft cloth and denatured alcohol.
Coat shaft area bellows
assembly must slide over to
seat with mating ring.
Coat inside of
bellows assembly

Page 5 of 7
F−1031, Section 4209 Rev: 01/03/07
Packing −Braided Flexible Graphite (BFG)
Waterous uses a braided graphite fiber, with reinforced flexible graphite yarns
and high purity graphite filament yarns that appear on the corners as well as
throughout the body of the packing. The graphite reinforcement allows the
flexible graphite yarns to provide greater tensile strength.
This type of packing reduces the frictional heat created between the shaft and
the I.D. of the packing. By dissipating the heat through the cross section of the
packing, the heat is transferred to the packing gland and the seal housing.
WARNING
!
Packing Gland and Pump Body Temperature Hazard. May result in
serious burns.
Heat is dissipated through the cross−section of the packing, transferring
the heat to the packing gland and pump body.
Packing Removal
WARNING
!
Truck movement hazard.
May cause serious personal injury.
Stop engine, set the parking brake and chock the wheels before going
under truck to remove packing.
1. Remove the unbalanced nuts, flat washers and packing gland halves
from one end of the pump.
2. Engage the pump per appropriate operating instructions. Operate the
pump gradually increasing the discharge pressure until the packing is
forced out of the seal housing. Pressure in excess of 300 psi (20.7 bar)
may be required.
CAUTION
Pump overheating hazard.
May cause damage to the pump.
Circulate enough water through the pump to prevent overheating. Do not
pressurize the pump over 600 psi (41.4 bar).
3. If all the packing is not forced out, it may be necessary to remove the re-
maining packing by hand, using a pick or similar device. Waterous has a
packing removal tool (P/N 5782) available for this purpose, see Figure 1.
4. Replace packing per instructions below, repeating the procedure for the
opposite end of the pump.
Figure 2. Packing Removal Tool
IL1931
Packing Installation
1. Before installing the new packing, be sure that all of the old packing is
removed from the seal housing.
2. Be sure that the seal housing and the shaft are clean and free of any
packing residue.
3. Lightly lubricate the packing ring I.D. and O.D. with mineral oil, automo-
tive grease or engine oil for installation purposes.
4. Make sure packing is clean.
5. Carefully install one ring of packing. With the aid of packing glands, push
the packing into the seal housing as far as possible. Repeat this opera-
tion with each ring, staggering the joints at least 90_apart. Install the
packing rings until the top of the last ring is about 1/4 inch from the end
of the seal housing (at least 1/8 inch is required for the packing gland
nose entrance into the stuffing box), see Figure 3.

Page 6 of 7
F−1031, Section 4209 Rev: 01/03/07
NOTE: Be sure that the packing joints are staggered at least 90_apart.
6. Install packing glands, nuts and washers. Tighten gland nuts one flat be-
yond finger tight, see Figure 3.
NOTE: The milled slot on the nut should face the gland.
7. Adjust packing as required per instructions on the next page.
Figure 3. Packing Gland Tightening
Final Assembly
1. Connect pump to intake and discharge piping.
2. Connect propeller or drive shaft transmission.
3. Connect drain lines, electrical wiring and similar equipment to pump and
accessories.
4. Fill gear case with lubricant as described in transmission operation and
maintenance instructions.
Packing Adjustment
The pump packing is designed and adjusted to drip slightly during operation.
This is to cool and lubricate the packing. It is desirable to adjust the stuffing
box to maintain a leakage rate of 10 to 120 drops per minute when operating
at a discharge pressure of 150 psi (10.3 bar).
Leakage through the braided flexible graphite (BFG) packing may be at zero
or diminish to zero leakage and may not respond to loosening of the packing
nuts to restore leakage, see Adjustment Step 3. While the packing gland and
stuffing box and pump body may reach high temperatures during this time,
the impeller shaft will be protected from heat damage.
CAUTION
Pump overheating hazard.
May cause damage to the pump.
Circulate enough water through the pump to prevent overheating.
WARNING
!
Truck movement hazard.
May cause serious personal injury.
Stop engine, set the parking brake and chock the wheels before going
under truck to adjust packing.
1. Engage pump per appropriate operating instructions. Operate the pump
at the capacity pressure shown on the serial plate for ten (10) minutes.
CAUTION
Observe the stuffing box drip rate from the side of the truck.
2. Observe leakage. Normal leakage is 10−120 drops per minute. (Leakage
may be zero or diminished to zero occasionally).

Page 7 of 7
F−1031, Section 4209 Rev: 01/03/07
3. If drip rate is considered high, stop the engine and tighten the packing
gland nuts 1/2 to 1 flat (maximum of 1/6 of a revolution). Make appropri-
ate adjustments starting with 1 flat, when approaching the final adjust-
ment reduce to 1/2 flat. This reduces the possibility of over tightening.
Tighten the gland nuts equally to ensure that the packing gland
goes on straight. Gradually reducing leakage during the first hour of
operation will result in a better seal over a longer period of time.
CAUTION
Stopping the leakage entirely at this point will cause the packing to
overheat.
4. Operate the pump at the capacity pressure shown on the serial plate for
two (2) minutes to let packing run in, then observe the drip rate.
WARNING
!
Packing Gland and Pump Body Temperature Hazard. May result in
serious burns.
Heat is dissipated through the cross−section of the packing, transferring
the heat to the packing gland and pump body.
5. Repeat steps 3 and 4 until the drop rate is acceptable.
NOTE: After adjusting the packing, the pump must pass the follow-
ing vacuum test described below.
Vacuum Test
1. Remove all caps except openings without valves. Close all discharge,
intake and drain valves and other similar openings. Operate priming de-
vice to create a vacuum of about 22 in. Hg/.735 atmosphere in pump,
then stop primer and engine.
2. Watch the pressure gauge; if vacuum drops more than 10 in. Hg/.334
atmospheres in five (5) minutes, listen for air leaks around the packing
gland, gaskets, valves, etc.
3. Replace gaskets, re−adjust packing, repack or otherwise repair source of
trouble.
4. Repeat test.
Testing
Before a pump is returned to service, it is advisable to give it both hydrostatic and operational tests to check it for leaks and to make sure the pump operates properly.
Hydrostatic Testing
1. Connect pump to a hydrant or other pressurized water supply.
2. Close all drain lines and open discharge and priming valves.
3. Open hydrant until water runs out through discharge valves and dis-
charge pipe in priming pump. Close all valves. Be sure to evacuate all air
from pump.
4. Apply water pressure to pump for 15 minutes. Do not exceed 350 psi
(24.2 bar). With a portable light, check pump for leaks. If leaks are dis-
covered, tighten connections or attaching parts as necessary.
NOTE: If a mechanical seal is used, it may leak under hydrostatic pres-
sure. However, it should stop leaking after the seal faces are run−in
during operational testing.
5. After all leaks are eliminated, shut hydrant valve, drain pump completely
and disconnect intake hose.
Operational Testing
1. Operate pump at its maximum intended service pressure. Do not exceed
350 psi (24.2 bar) (450 psi, 31 bar with positive intake).
2. With a portable light, check pump for leaks. If leaks are discovered, stop
pump and tighten connections or attaching parts as necessary. Repeat
until all leaks are eliminated.
3. While pump is running, check for unusual noises, oil leaks, overheated
bearings, etc. If anything unusual is discovered, stop pump immediately
and determine the cause.