INSTALLATION
AND
OPERATION MANUAL
R 5 Series
Models 0025, 0040, 0063, 0100, 0101 and 0250 C/E
Single Stage Rotary Vane Vacuum Pumps
Page
GENERAL 2
Identification 2
Operating Principles 2
1.0 INSTALLATION 2
1.1 Unpacking 2
1.2 Location 2
1.3 Power Requirements 2
1.4 Vacuum Connections and Drip Legs 3
1.5 Oil Filling 3
2.0 OPERATION 4
2.1 Start-up 4
2.2 Gas Ballast 4
2.3 Process Gas 5
2.4 Stopping Pump 5
2.5 Water-Cooled Pumps (optional) 5
2.6 Oxygen Service Pumps 5
3.0 ROUTINE MAINTENANCE 6
3.1 Pump Oil 6
3.1.1 Oil Filter 6
3.1.2 Oil Type and Quantity 6
3.1.3 Oil and Filter Change 6
3.1.4 Oil Flushing procedure 7
3.2 Automotive-Type Oil Filter 8
3.3 Exhaust Filter 8
3.4 Inlet Flange 9
3.5 Vacuum Inlet Filter (optional) 9
3.6 Routine Maintenance Schedule 9
3.7 Overhaul Kit/Filter 9
4.0 TROUBLESHOOTING 9
5.0 LIMITED STANDARD WARRANTY 14
Technical Data 14
Parts List 15
Illustration of R 5 0025-0040 16
Illustration of R 5 0063-0101 17
Illustration of R 5 0250 18
Busch Factory Service Centers 19
We reserve the right to change the product at any time without any form of notification. The information in this pub-
lication is accurate to the best of our ability at the time of printing. Busch, Inc. will not be responsible for errors
encountered when attempting to perform tasks outlined in this publication which is copyright protected.
TABLE OF CONTENTS
1
GENERAL
Identification
For model identification, see the nameplate mounted on
the side of the exhaust box.
This manual is written to cover RA and RC versions of
models 0025, 0040, 0063, 0100, 0101 and 0250 with a
"C" or "E" appearing as the seventh character in the
model type number stamped into the nameplate. For
example, it would appear as follows:
RAXXXX-C
XXX-XXXX
When ordering parts, it is helpful to include the identifi-
cation code stamped into the side of the cylinder as well
as the serial number from the nameplate.
Operating Principles
All reference (Ref. XXX) numbers listed in the text and
on illustrations throughout this manual are related to the
drawings and parts list shown later in this publication.
All R 5 Series, Single Stage, Rotary Vacuum Pumps are
direct-driven, air-cooled, oil-sealed, rotary vane pumps
that operate as positive displacement pumps. They
consist of a rotor positioned eccentrically in a cylindrical
stator (see Fig. 1). The rotor has three radially sliding
vanes which divide the pump chamber into three seg-
ments. When the rotor spins, centrifugal force pushes
the vanes, which glide in the slots, towards the wall of
the cylinder. The rotor has three vanes which divide the
pump chamber into three segments. The gas to be
pumped enters at the inlet port, passes through the inlet
screen and the open anti-suck-back valve into the
pump chamber. As the rotor rotates, the inlet aperture
is closed, the gas is compressed and forced out through
one-way valves between the pump cylinder and the
exhaust box. This operation is repeated three times
each revolution.
1.0 INSTALLATION
1.1 Unpacking
Inspect the box and pump carefully for any signs of
damage incurred in transit. Since all pumps are ordi-
narily shipped FOB our factory, such damage is the nor-
2
mal responsibility of the carrier and should be reported
to them.
Remove the nuts from the bottom of the box/crate and
pull the pump out of the container, then unscrew the
studs from the bottom of the rubber feet.
The inlet port of the pump is covered with a plastic cap
prior to shipment to prevent dirt and other foreign mate-
rial from entering the pump. Do not remove this cover
until the pump is actually ready for connection to your
system.
1.2 Location
The pump must be installed in a horizontal position on
a level surface so that the pump is evenly supported on
its rubber feet. Allow sufficient air space between the
pump and any walls or other obstructions; adequate
ventilation must be provided for the fans on the pump
and motor (i.e., do not locate the pump in a stagnant air
location).
Whenever the pump is transported, be sure to drain the
oil prior to shipping to avoid vane breakage when
restarting the pump.
Do not tip the pump over if it is filled with oil.
Locate the pump for easy access to the oil sight glass
(Ref. 83) in order to inspect and control the oil level
properly. Allow clearance at the exhaust flange area to
provide service access to the exhaust filters.
1.3 Power Requirements
The schematic diagram for the electrical connection is
located in the junction box or on the nameplate of the
pump motor.
The motor must be connected according to the electri-
cal codes governing the installation. The power supply
must be routed through a fused switch to protect the
motor against electrical or mechanical overloads. The
motor starter has to be set consistent with the motor
current listed on the motor nameplate.
If the pump is supplied with a manual motor starter, it is
preset at the factory in accordance with the customer’s
specification. For other voltage requirements, contact
the factory for motor and/or starter information.
Note: See the motor manufacturer’s manual for start-
up maintenance of the motor.
Correct direction of rotation is marked by an arrow on
the motor fan housing and is counterclockwise when
looking at the motor from the motor's fan side.
All R 5 series pumps are designed to handle air.
Vapor in the air stream can be tolerated when the
pump is operated within certain operating parameters
as defined by Busch, Inc. Engineering (see Section
2.2 - Gas Ballast). When you desire to use the pump
on an air stream that contains vapors, contact Busch,
Inc. Engineering for operating recommendations; oth-
erwise, the warranty could be void.
3
1.4 Vacuum Connections and Drip Legs
Use a line size to the vacuum system that is at least as
large as that of the pump inlet. Smaller lines will result
in lower pumping speeds than the rated values.
Install a drip leg and drain on the vertical pipe near the
pump inlet. Also, when installing discharge piping, a
drip leg should be installed. Drain the drip legs often to
remove any condensation which may have collected.
If more than one vacuum pump or a receiver tank is
connected to a common main line, each pump should
have its own manual or automatic operated shut-off
valve or positive action check valve. The built-in, anti-
suck-back valve should not be used as a shut-off valve
for the vacuum system.
Remove the plastic protective cap from the inlet port
prior to connection of the pump to the system. Vertical
connection of the vacuum line can be made directly to
the pump inlet (Ref. 260).
Type and size of the inlet connections of the R 5 Series
pumps are shown in the TECHNICAL DATA page 14.
If the gas that is pumped contains dust or other foreign
solid particles, a suitable inlet filter (10 micron rating or
less) should be connected to the inlet port. Consult the
factory for recommendations.
1.5 Oil Filling
The pump is shipped without oil. After level installation,
and after correct rotation has been established and with
the pump switched "off" and secured against accidental
start-up, fill the pump with the recommended vacuum
oil through the oil filling port (Ref. 88), observing the
"MAX" and "MIN" position at the oil sight glass (Ref.
83).
CAUTION: The built-in, anti-suck-back valve
is not positive action; do not use it as a sys-
tem check valve.
Exhaust
Inlet
Exhaust filter
Gas ballast
(RA)
Rotor
Anti-suckback valve
Inlet screen
Vane
Automotive type
spin-on filter
Main oil feed line
Exhaust valve (RA)
Oil return valve (RA)
Oil sight glass
Oil return line to
inlet (RC)
Fig. 1 - Basic R 5 Pump
CAUTION: After the electrical connection
has been made, but before the pump is
filled with oil, the rotation of the motor
must be checked. Open the inlet port and
jog the motor briefly to make sure rotation
is correct. If it runs backwards and if it is
wired three phase power, reverse any two
leads of the three at the power connection.
4
Non-detergent oil should be used. Do not use
detergent motor oil as additives in detergent oil will
plug exhaust filter elements and shorten their life.
It is recommended that Busch R500 Series oil be used
to receive the best performance from your vacuum
equipment. R500 Series oil is a high quality vacuum oil
that will give longer running time between oil changes,
will provide better lubrication at high operating temper-
atures, and will prolong the life of exhaust filter ele-
ments. This oil can be obtained directly from Busch,
Inc. in Virginia Beach, Virginia.
The strict use of Busch oils and parts from the day of
purchase can extend the Limited Standard Warranty to
three years. Contact Busch, Inc. in Virginia Beach,
Virginia for details.
For general applications, use R530 in all models cov-
ered by this manual. Use R590 or R570 in pumps that
are operated in high ambient temperatures (above
90°F) or when the oil carbonizes (turns black) before
the change interval. Use R590 or R570 on 0250
pumps. Contact the factory for recommendations when
using other oils.
The TECHNICAL DATA chart on page 14 gives the
approximate quantities of oil required for each pump.
The oil capacity chart should only be used as a guide,
since oil capacity may be slightly lower, depending on
whether the pump was filled previously, and whether all
components such as oil filter, oil lines, etc., were
allowed to completely drain. Use only the sight glass
reading for proper level. Never overfill!
For ambient operating temperatures lower than 41°F,
use Busch R580 synthetic oil. If this does not help
(where the pump has difficulty starting due to high oil
viscosity), contact the factory in Virginia Beach,
Virginia.
Replace the oil fill plug (Ref. 88), making sure that the
gasket (Ref. 89) is in place and properly seated and
secured. Some pumps are equipped with an exhaust
pressure gauge as an integral part of the oil fill plug.
Switch the power back into the "on" position.
2.0 OPERATION
2.1 Start-up
Check rotation of the motor as described in Section 1.3
- Power Requirements.
Fill the pump with oil as described in Section 1.5 - Oil
Filling.
Start the pump and immediately close the inlet. Run the
pump for a few minutes before checking the oil level
again. With the pump shut off, the oil level should be
visible in the oil sight glass (Ref. 83), between the "MIN"
and "MAX" mark.
Add oil, if necessary, but only add it when the pump has
been shut off and the circulating oil has had sufficient
time to return to the oil sump.
Note: The oil separated by the exhaust filter element
forms droplets on the outside of the exhaust filter that
collect at a low point in the upper half of the exhaust
box. From there the collected oil is drained back to the
oil sump via an oil check valve (Ref. 275) which opens
on R 5 RA model pumps when the pump is shut off. It
is necessary to shut off the RA model pumps after every
8 hours of operation to allow the check valve to open.
If the pump is not shut off after this time period, it is pos-
sible to starve the pump of oil since the oil is not allowed
to drain back into the oil sump and/or oil droplets may
be blown out of the exhaust. If the pump is operating at
high pressure it may be necessary to shut it down soon-
er than 8 hours.
On R 5 (Standard) RC model pumps, the collected oil is
drawn continuously during operation of the vacuum
pump to the inlet flange (Ref. 260) via the oil return line
(Ref. 290). The oil return line is connected directly to
the area of the exhaust box, downstream of the exhaust
filter, which is at atmospheric pressure. Therefore, a
constant amount of air is sucked into the pump, which
is an additional reason that the R 5 Standard Series
Pumps do not achieve as low a vacuum as the R 5
Series Super Vacuum Pumps. RC model pumps can
run continuously without having to shut them off for the
oil to drain back.
2.2 Gas Ballast
All RA Series pumps are equipped with a gas ballast
valve. The gas ballast valve (Ref. 440) is located
between the inlet port and the exhaust box. RA series
pumps are equipped with a permanent gas ballast
which cannot be shut off unless the sintered filter is
removed and the orifice plugged. Larger pumps are
equipped with an adjustable gas ballast valve.
The adjustable gas ballast valve should normally be left
open. Its primary function is to prevent water vapor
from condensing in the pump. Condensation causes
emulsification of the oil, loss of lubricity, and possible
rotor seizure.
WARNING: Keep the oil fill plug tight as
pressure in the exhaust box could cause
bodily injury if the plug is blown out. Do not
fill/add the pump with oil through the
exhaust/inlet ports as there is danger of
breaking the vanes!
5
2.3 Process Gas
The R 5 series pumps are designed to pump air and are
not intended for use when water vapor is being
pumped. In some applications, when the quantity of the
water vapor is moderate, R 5 pumps have been used
with good results. On these occasions, the pump is run
until it is up to operating temperature before it is allowed
to pump the process gas. The pump is also operated
for a period of time off process and on air (to clear it of
process gas) before it is shut down. This operating
technique prevents the vapor from condensing in the
pump. Before attempting to pump a gas laden with
water vapor, contact Busch Engineering for advice.
2.4 Stopping Pump
To stop the pump, turn off the power. The pump has a
built-in, anti-suck-back valve (Ref. 251 thru 255) to pre-
vent the pump from rotating backwards when it is shut
off.
Install an automatic operated valve (such as a check
valve) in front of the pump, if more than one pump is
pumping on the same line or if there is a sufficient vol-
ume of vacuum in the system to cause the pump oil to
be drawn into the piping when that pump is shut down.
All R 5 Series pumps are vented internally to atmos-
pheric pressure through venting holes that are next to
the exhaust valve assembly.
2.5 Water-Cooled Pumps (optional)
Water-cooled pumps are cooled by circulating the oil
through a shell-and-tube type heat exchanger. The cir-
culation of the pump oil through the shell is created by
vacuum in the pump, but the circulation of the cooling
water through the tubes is thermostatically controlled.
The flow rate of the cooling water is controlled by a ther-
mostatically activated valve (see Fig. 2) that senses,
through a capillary bulb mounted in the exhaust box,
the pump's oil temperature as it is discharged from the
compression chamber. The valve will open at its set
point and close at approximately 3°F to 5°F below the
set point. The valve set point is adjustable as follows:
(a) Rotate the valve adjustment screw counterclock-
wise to cause the valve to open at a higher tempera-
ture. This makes the pump run hotter.
(b) Rotate the valve adjustment screw clockwise to
make the valve open at a lower temperature. This
makes the pump run cooler.
The thermostatic valve can be manually opened by
inserting a screwdriver under each side of the spring
guide and prying the spring and guide upward away
from the valve body.
The water cooling option can be used to cool pumps
operating in high ambient temperatures, or it can be
used to maintain a pump at elevated temperatures to
prevent condensation inside the pump in wet applica-
tions. Contact Busch Engineering in for details.
2.6 Oxygen Service Pumps
Oxygen service pumps must be used in oxygen
enriched applications that are defined as any applica-
tion which has a process gas that is 25% or more oxy-
gen. If this pump is contaminated by organic com-
pounds, do not attempt to use it on oxygen service until
it has been decontaminated.
These pumps have been manufactured, solvent
washed (to remove organic contaminants) and assem-
bled according to the latest technical standards and
safety regulations. If this pump is not installed properly
or not used as directed, a dangerous situation or dam-
age might occur. It is mandatory that these operating
instructions be read and understood prior to vacuum
pump installation and start-up!
CAUTION: Do not use the anti-suck-back
valve as a system check valve for your vac-
uum system. Do not depend on the anti-
suck-back valve to prevent pump oil from
migrating through the inlet into the system
when the pump is shut down.
Fig. 2 - Water-cooled Pump
Thermostatic
valve
WARNING: This pump is filled with a special
operating fluid. Do not use any other type
of fluid, oil and/or grease. Use one of the
following:
• Fomblin LC 250
• Tyreno Fluid 12/25V (perfluorinated polyether)
• KRYTOX ® Vacuum pump fluid by Du Pont
Company
If you have any questions, please phone our
Customer Service Department for more information.
6
For overhaul/repair of oxygen service pumps,
Busch Inc. strongly recommends that all major repair
operations be conducted at the factory. Improper
handling of repairs could result in extreme
danger to personnel operating the pump.
3.0 ROUTINE MAINTENANCE
R 5 Series pumps require very little maintenance; how-
ever, to insure optimum pump performance, the follow-
ing steps are recommended.
3.1 Pump Oil
3.1.1 Oil Level
With the pump installed relatively level, make sure that
there is sufficient clean oil in the pump. The oil level
should be observed on a daily basis and/or after 8
hours of operation and should be replenished if it drops
below the 1/4 mark on the oil sight glass on pumps with
one sight glass.
On RA Series pumps, you must first shut the pump off
in order to let the oil flow back into the oil sump prior to
checking the sight glass. Allowing insufficient time for
the oil to drain back into the sump on RA Series pumps
prior to adding oil could result in overfilling.
Oil level readings should be done only when the pump
is turned off. Oil can be added to the oil fill port (Ref.
88) if the pump is shut off and the circulating oil has suf-
ficient time to return to the oil sump. The oil might
appear to be foamy, which is a normal phenomenon
with aerated oil.
Under normal circumstances, it should not be neces-
sary to add or drain oil from the pump between recom-
mended oil changes.
A significant drop in oil level means there is an oil leak
or that an exhaust filter is broken, and the pump should
be smoking excessively. It is normal for the oil to be
foamy and light in color in an operating pump.
However, if the oil is milky colored, it is an indication
that water is present in the oil. Normally, by operating
the pump for an extended period, with the inlet suction
blanked off and the gas ballast (Ref. 440) open on RA
pumps, the water will be purged from the oil. If the oil
is dark colored, it is contaminated or carbonized and
must be changed. Depending on the severity of the
contamination, a thorough flushing may be needed.
Contact the factory for flushing oil (Busch R568) and
refer to Section 3.1.4 for the flushing procedure.
3.1.2 Oil Type and Quantity
See Section 1.5 - Oil Filling for details on oil type and
quantity.
3.1.3 Oil and Filter Change
See Section 1.5 and the Technical Data on page 14 for
details on oil type and quantity.
Check the oil for contamination on a weekly basis by
shutting the pump off and draining some of the oil into
a small glass or a similar transparent container through
the oil drain port (Ref. 95).
Oil life is dependent upon the conditions to which it is
exposed. A clean, dry air stream and an oil operating
temperature under 210°F are ideal conditions. When
using R530 (hydrocarbon oil), it is recommended that
oil changes are made every three (3) to four (4) months
or 500 to 750 hours of operation, or as necessary if high
heat is contaminating the oil. The use of Busch R570
(synthetic) or R590 (semi-synthetic) oil may significant-
ly extend the operating hours between oil changes
under ideal conditions. However, you may need to flush
out the pump before changing. Contact the factory
Service Department for advice. Oil samples should be
taken regularly when exceeding the 500-750 hour rec-
ommendation.
Excessive Heat
When the pump is subjected to operating conditions
that will cause the oil to be heated above 210°F, the oil
will carbonize and become contaminated after a rela-
tively low number of operating hours. The higher the
temperature, the quicker the oil becomes contaminated.
CAUTION: Do not add oil while the pump is
running since hot oil vapor may escape
through the oil fill port.
CAUTION: When changing the oil and fil-
ters, it may be necessary to flush the pump
to remove any build-up of degraded oil from
the sumps, oil lines, radiators, etc., to
ensure proper oil flow through the pump.
Reduced oil flow, especially through radia-
tors and cooling coils, can cause mechani-
cal damage or extreme overheating, which
could cause the oil vapors to ignite.
CAUTION: Insufficient oil quantity in the
pump has the potential, under certain con-
ditions, to lead to self-ignition of the
remaining oil in the pump.
WARNING: Always take the necessary pre-
cautions concerning personal protective
equipment when changing oil and make
sure the pump is switched to "off" so that
accidental starting will not occur. Oil tem-
perature can reach 212°F and may pose a
danger of scalding.
7
If the oil temperature is too severe, Busch R570 (syn-
thetic) or R590 (semi-synthetic) oil should be used to
withstand the elevated temperatures. If synthetic oil is
used, the pump should be flushed with Busch R568 oil.
Contact the factory for instructions on the flushing pro-
cedure. Auxiliary oil cooling is the most practical
approach to a severe heating problem.
Contaminated Air Stream
When the air stream contains a solid and/or liquid that
can contaminate the oil, it must be changed more often.
If the air stream contains a small percentage of con-
taminates and/or they are slightly aggressive* (mild
acids, etc.), synthetic oil, such as Busch R570, will
resist breakdown better than the standard Busch R530.
The solution is to install a filter or knock-out pot to keep
the contaminates out of the pump.
*Process air streams with a large percentage of contaminates and/or
more than slightly aggressive contaminates must use a chemical duty
pump.
Oil change intervals can only be established by experi-
ence with the pump operating in the actual conditions
(see previous paragraph for some of the conditions).
Develop the oil change interval by periodically checking
an oil sample removed from the pump. When the oil
sample has become dark in color (from solids and car-
bonized particles) or is milky looking (from water), it is
time to discard it. As mentioned before, a thorough
flushing may be required.
3.1.4 Oil Flushing Procedure
Flushing is needed under certain conditions. Some
pumps will be beyond flushing and will need to be over-
hauled.
To help determine if flushing is needed, observe the
condition of the oil as it is drained from the pump. Is it
black and tar like or contaminated in any way? Was the
pump noisy, overheating, or was the motor overload
shutting the pump off? How old is the pump and when
was the last time the oil was changed?
If the above conditions exist or you don't know when the
last oil change was performed further investigation is
needed. Also, when changing from one oil type such as
R530 to another type such as R590 or R570 it will be
beneficial to flush. Although the oils are compatible,
mixing a lesser grade oil such as R530 with a synthetic
oil like R570 will reduce the effectiveness of the syn-
thetic oil.
All of the oil will be removed and replaced with the
flushing oil (Busch R-568), and eventually that will be
replaced by whatever Busch oil is needed for your par-
ticular application. Have enough oil and oil filters on
hand for a couple of flushes. The following describes
the steps in the flushing procedure:
Shut the pump off and drain all the oil from the pump
and remove the access plates (Ref. 205) from the
exhaust box (Ref. 075). Remove the metal baffle (Ref.
078) and take a good look at the internal walls of the oil
sump. If the walls are discolored but have no build up
of any kind one can proceed with the flushing. If gelled
or burnt oil is clinging to the walls this material must be
scraped and removed prior to flushing. Proceed by
scraping and cleaning as much of the exhaust box as
possible. The more debris that is removed now the
more effective the flushing will be later. Re-install the
metal baffle, cover and proceed with the flushing. At
this point one must remember that the oil lines and oil
cooler might also be plugged to a point where no
amount of flushing will make a difference and a com-
plete overhaul will be the only option. Depending on
the severity of the oil contamination flushing may be a
last ditch effort.
Drain all of the oil from the pump. The more contami-
nated oil you remove now the more effective the oil
flushing will be.
Remove the oil filter (Ref. 100) and install a new one. It
is recommended that you do not change the exhaust fil-
ter or filters until after the flushing to prevent contami-
nation of any new filters.
Fill the exhaust box with the proper amount of flushing
oil (Busch R-568).
If possible run the pump with the inlet closed and off of
the process. Run the pump for approximately six hours,
shut the pump off and drain a small sample of oil into a
clear container.
Examine it. If it is clear to amber run the pump for
another six hours and examine it again. If after the first
six hours it is black drain it and fill again using another
new oil filter.
If after the second flushing the oil still remains black the
pump may have too much contaminated oil in it to flush
out properly. There may be residue remaining in the
lines and cooler that will not flush out. An overhaul will
be necessary.
If after the second six hour period the oil still remains
clear to amber in color drain it, change the oil filter and
fill with the regular oil. At this point also change the
exhaust filters.
Run the pump with a fresh charge of the oil to be used
in your application (not R-568), and monitor the operat-
ing conditions closely. Check for noise, overheating
and oil condition until a regular oil change schedule can
be established.
8
Do not let the oil turn black. Change it before it fails. If
the oil is kept in good condition the pump will last for
years. If the oil starts to turn black do not hesitate to
flush again. Keeping on top of the oil changes will pre-
vent costly overhauls.
If you are just switching from one type of oil to another
a single six hour flush is all that is necessary (follow the
above instructions). Remember to change to a new
exhaust filter or filters after the flushing and not before.
3.2 Automotive-Type Oil Filter
The pump is equipped with an automotive-type oil filter
(Ref. 100). When replacing the automotive-type oil fil-
ter, use only a Busch genuine filter.
Note: Make sure to tighten the Busch oil filter secure-
ly against the aluminum sealing surface so that leaks
will not occur.
3.3 Exhaust Filter
Every nine (9) to twelve (12) months, or as necessary,
replace the exhaust filter elements. The service life of
the exhaust filters varies widely with pump application.
It is only necessary to change the filters when the ele-
ments become clogged with foreign material or burned
oil. Indications of clogged filters are smoke and oil mist
coming from the pump exhaust, higher than normal
motor current or oil leaking from the gas ballast valve
on RA models.
A pressure gauge (Ref. 90) is supplied with your R 5
vacuum pump as part of the oil fill plug. This gauge has
a green field and a red field. A pressure within the
green field would indicate normal pressure. Any pres-
sure in the red field (for a continuos period of time)
requires an immediate change of the exhaust filter(s).
In order to replace the filter, remove the four socket
head cap screws (Ref. 146 on 0025 through 0101 / Ref.
142 0n 0250) and lockwashers (Ref. 143) retaining the
exhaust port housing (see Fig. 3). Pull the housing off
the exhaust box and set it aside. Use a slotted head
screw driver to loosen the exhaust filter retaining spring,
then rotate and remove the spring (see Fig. 4). Pull the
filter cartridge (Ref. 120) out of the exhaust box.
To field test an exhaust filter element, remove it from
the pump, allow it to cool, clean the sealing end (or O-
ring end), and use compressed air to blow through the
element. Apply approximately 3 to 6 psi (maximum
allowable operating pressure across the filter).
Use a shop rag to seal off the connection between the
air hose and the filter. If you can blow through it, the
element is good. If not, discard it and install a new one.
The filter cannot be cleaned successfully. Visually
inspect the filter element for cracks.
Reinstall the filter elements. Make sure the open end of
the element is properly seated down in its recess in the
exhaust box with the O-ring (Ref. 121) correctly posi-
tioned. Retain the filter with the spring clip, tighten the
WARNING: Do not inhale through the filter
or allow your mouth to come in direct con-
tact with the filter.
Fig. 4 - Removing the Filter Spring
Fig. 3 - Removing the Exhaust Housing
WARNING: If the gas entering this pump is
a health hazard, use rubber gloves and all
necessary personal protection equipment
when performing the exhaust filter replace-
ment operation.
WARNING: Wear safety glasses when
installing or removing the spring retainers.
The retainers can, if not secured correctly,
slip off and fly out of the exhaust box.
9
ter material as practice determines.
The radiator (Ref. 241) on model 0250, the fan cover
(Ref. 340) on the 0025 through 0101 models and (Ref.
244) on the 0250 model should be inspected regularly
for debris. Soiling prevents cool air intake and may lead
to overheating of the pump.
Drain drip legs on inlet and exhaust piping.
3.7 Overhaul Kit/Filter
An overhaul kit containing a set of gaskets and O-rings,
vanes, bearings and bearing sleeves, shaft seals and
taper pins, is available from the factory.
Also, a filter kit containing oil drain plug, gaskets, auto-
motive-type oil filter (where applicable), exhaust filter,
and synthetic baffle strainer (where applicable), is avail-
able from the factory.
When ordering, please specify pump size and model (a
4-digit suffix after size), and serial number.
4.0 TROUBLESHOOTING
4.1 Trouble
Pump does not reach "blank-off" pressure,
which is the lowest absolute pressure (best
vacuum) when running with the inlet closed
via a blank flange or a valve; or the pump
takes too long to evacuate the system.
Blank-off pressure can be measured by
using a good quality capsule gauge.
Possible Cause:
Contaminated oil is the most common cause of not
reaching the ultimate pressure.
Remedy:
Shut off pump, after operating temperature has been
reached, drain the warm oil from pump and exchange
automotive-type oil filter (where applicable), if neces-
sary. Flush and fill pump with new oil and take new
blank-off measurement after operating temperature is
reached (at least 20-30 minutes).
Possible Cause:
Vacuum system or vacuum piping not leak-tight.
Remedy:
Check hose and pipe connections for possible leak.
tension screw until the filter is secure. Place the
exhaust port gasket and cover in position on the
exhaust box and retain with the cap screws.
3.4 Inlet Flange
The standard inlet flange assembly contains an inlet
screen (Ref. 261) which may require occasional clean-
ly. The frequency of cleaning can only be determined
by experience and is affected by hours of operation and
particle size being trapped. An optional vacuum inlet fil-
ter is offered and can help minimize the need or fre-
quency of cleaning the inlet screen.
To clean the screen, disconnect the flange from the
process piping. Remove the four screws and lock-
washers (Ref. 265/266). Remove the inlet flange (Ref.
260). Remove the screen (Ref. 261) and clean with
compressed air. After cleaning, install the screen and
inlet securing them with the screws and lockwashers.
Make sure the O-ring (Ref. 265) is in place prior to
securing the screws. Reattach the process piping to
the inlet.
3.5 Vacuum Inlet Filter (optional)
If the pump is equipped with a special vacuum inlet fil-
ter in applications where powder, dust or grit is present,
the filter cartridge should be cleaned on a weekly basis,
or as required, depending on the amount of foreign par-
ticles to which the pump is exposed.
3.6 Routine Maintenance Schedule
See the motor manufacturer’s manual for the periodic
motor maintenance.
Note: Lack of proper maintenance can result in
blocked filters, radiators, oil lines, etc. This condition
can lead to excessive heat causing mechanical failure
or ignition of the oil vapors.
Daily: Visually check oil level (see 3.1.1 and 3.1.2).
Weekly: Check oil for contamination (see 3.1.3).
Inspect inlet filter (see 3.5).
Every three (3) or four (4) months, 500 to 750
hours of operation, or as necessary: See 3.1.3
and 1.5. Drain and discard oil from the hot pump.
Replace the automotive-type oil filter and refill with
fresh oil through the fill plug (see 3.1.2 through 3.1.3
and 3.2).
Every nine (9) to twelve (12) months, or as
necessary: Replace exhaust filter elements (see
3.3).
As necessary: Check and/or clean the standard inlet
screen. If the optional inlet filter is used, replace the fil-
Possible Cause:
Wire mesh inlet screen plugged (Ref. 261).
Remedy:
Clean wire mesh inlet screen. Install inlet filter if prob-
lem repeats frequently.
Possible Cause:
No oil or not enough oil in oil reservoir.
Remedy:
Shut off the pump, add the necessary oil, or if oil seems
contaminated, drain balance of oil from pump,
exchange automotive oil filter, and refill with fresh oil.
Flush if necessary.
Possible Cause:
Automotive-type oil filter is dirty or clogged (where
applicable).
Remedy:
Replace automotive-type oil filter, exchange oil, if nec-
essary, and refill with fresh oil.
Possible Cause:
Inlet valve plate (Ref. 251) stuck in closed or partially
open position due to contamination.
Remedy:
Disassemble inlet valve and screen. Clean as required.
Possible Cause:
Oil tubing fittings are loose and leaking. Oil return line
broken on RC model.
Remedy:
Replace or retighten the oil fittings or oil tubing.
Replace only with same size tubing.
Possible Cause:
Shaft seal leaking.
Remedy:
Replace the shaft seal following disassembly and
assembly steps outlined in the Maintenance and Repair
Manual. Check the shaft seal. It should have a spring
installed inside and around the shaft sealing lip.
Possible Cause:
Exhaust valve (Ref. 159) is not properly seated or it is
partially stuck open (RA models only).
Remedy:
Follow disassembly and assembly steps outlined in the
Maintenance and Repair Manual or contact the nearest
Busch Factory Service Center.
Possible Cause:
Vanes are blocked in the rotor or they are damaged.
Remedy:
Free vanes or replace with new ones following disas-
sembly and assembly steps outlined in the
Maintenance and Repair Manual or contact the nearest
Busch Factory Service Center.
Possible Cause:
Radial clearance between the rotor and cylinder is no
longer adequate.
Remedy:
Follow disassembly and assembly steps outlined in the
Maintenance and Repair Manual on resetting the radial
clearance correctly or contact the nearest Busch
Factory Service Center.
Possible Cause:
Internal parts worn or damaged.
Remedy:
Follow disassembly and assembly steps outlined in the
Maintenance and Repair Manual and replace worn or
damaged parts or contact the nearest Busch Factory
Service Center.
Possible Cause:
Radial clearance between the rotor and cylinder is no
longer adequate.
Remedy:
Follow disassembly and assembly steps outlined in the
Maintenance and Repair Manual on resetting the radial
clearance correctly or contact the nearest Busch
Factory Service Center.
Possible Cause:
Internal parts worn or damaged.
10
11
Remedy:
Change to R580 vacuum oil if very cold, or warm up oil
before starting the pump.
Possible Cause:
Pump runs in the wrong direction.
Remedy:
Check for correct rotation which is counterclockwise
when looking at the motor from the motor's fan side.
Reverse any two leads on the motor to change the
direction of rotation.
Possible Cause:
Pump is overfilled with oil or wrong kind of oil is used.
Remedy:
Correct the oil level and quality per Section 1.5 and use
recommended motor oil.
Possible Cause:
Exhaust filters in exhaust chamber are clogged and
appear burned black with pump oil.
Remedy:
Replace exhaust filters, maintain proper oil condition,
oil level, and use only Busch recommended vacuum oil
and filters.
Possible Cause:
The exhaust filter is clogged due to process material.
Remedy:
Contact the factory in Virginia Beach, Va. for recom-
mendations or proper filter cartridge.
Possible Cause:
Loose connection in motor terminal box; not all motor
coils are properly connected. Motor operates on two
phases only.
Remedy:
Check motor wiring diagram for proper hookup, espe-
cially on motors with six internal motor windings, tight-
en and/or replace loose connections.
Possible Cause:
Foreign particle in pump; the vanes broken; the bearing
Possible Cause on RC Models Only:
The oil return line (Ref. 290) is connected directly to
atmospheric pressure in the exhaust area. On small
model pumps, a fairly large amount of air is sucked
through the oil return line, and it may not be possible to
reach 15 torr or 29.4 inches Hg. blank-off on the inlet of
the pump under these conditions.
Blank-off of 29.4 inches Hg or 15 torr can be reached by
temporarily disconnecting and closing the oil return line;
also by squirting oil through the exhaust opening into
the exhaust filter area. Oil will be sucked into the oil
return line, and no air will reach the inlet, thus affecting
the "blank-off' pressure.
4.2 Trouble
Pump will not start.
Possible Cause:
The motor does not have proper supply voltage or is
overloaded; motor starter overload settings are too low
or wrong setting; fuses are burned; or wire is too small
or too long, causing a voltage drop to the motor.
Remedy:
Check correct supply voltage; check overload settings
in motor starter for size and setting according to motor
nameplate data; check fuses; and install proper size
wire. If ambient temperature is high, use larger size
overloads or adjust setting 5% above nominal motor
nameplate value.
Possible Cause:
Pump or motor is blocked.
Remedy:
Remove fan cover and try to turn pump and motor by
hand. If frozen, remove motor from pump and check
motor and pump separately. If pump is frozen, disas-
semble completely per the Maintenance and Repair
Manual and remove foreign objects in the pump or
replace broken vanes.
4.3 Trouble
Pump starts, but labors and draws a very
high current.
Possible Cause:
Oil too heavy (viscosity too high) or ambient tempera-
ture below 5 degrees C (41°F).
is seizing.
Remedy:
Follow disassembly and assembly steps outlined in the
Maintenance and Repair Manual and remove foreign
parts, and replace vanes and bearings or contact the
nearest Busch Factory Service Center..
4.4 Trouble
Pump discharges smoke at the exhaust port
or expels oil droplets from the exhaust.
Possible Cause:
Exhaust filter is not properly seated with O-ring (Ref.
121) in filter base or filter material is cracked.
Remedy:
Check condition and check for proper seating of
exhaust filters. Replace if necessary. Also, check filter
spring clips for tightness.
Possible Cause:
Exhaust filter is clogged with foreign particles.
Remedy:
Replace exhaust filter.
Possible Cause:
The oil return valve (Ref. 275) is stuck open on RA/RB
pumps. Proper function is that when blowing into check
valve, it should close. When applying vacuum on it,
check valve should open.
Remedy:
Free or replace the oil return check valve.
Possible Cause:
If RA/RB Series vacuum pumps run continuously over
8 hours without ever being shut down, it may be possi-
ble that oil accumulates behind the exhaust box cover
to the extent that oil is blown out of the exhaust with the
exhaust gas.
Remedy:
Shut pump down during break periods or install an addi-
tional oil return line assembly. Check that oil return
valve (Ref. 275) is free and drains oil back into the
pump when the RA/RB Series pump is stopped.
Possible Cause:
Oil return line (Ref. 290) on RC Standard pump is
clogged or broken.
Remedy:
Free clogged line or replace. Check that oil is being
drawn out of the exhaust filter area while the vacuum
pump is operating.
Note: An oil filling plug with pressure gauge is provid-
ed on all R 5 Series pumps, so that the pressure in front
of the exhaust filters can be monitored. The green field
indicates that the filters are still effective. Back pres-
sure that causes a continuous reading in the red field
requires immediate change of exhaust filters (Ref. 120).
4.5 Trouble
Pump runs very noisily.
Possible Cause:
Coupling insert worn.
Remedy:
Replace coupling insert in motor/pump coupling.
Possible Cause:
Bearing noise.
Remedy:
Follow disassembly and assembly steps outlined in the
Maintenance and Repair Manual and replace bearings.
Possible Cause:
Vanes stuck.
Remedy:
Follow disassembly and assembly instructions outlined
in the Maintenance and Repair Manual and replace
vanes. Use only recommended Busch oil and change
oil more frequently.
4.6 Trouble
The pump runs very hot. See Technical Data
for typical oil sump temperature.
Note: The oil temperature with a closed inlet should be
approximately 185-225°F depending on pump type. At
24 in. Hg, the oil in the pump can go above 225°F.
12
WARNING: Do not apply pressure or vacu-
um by mouth.
13
Possible Cause:
Pump was operated for an extended period of time in
the wrong rotation.
Remedy:
Inspect vanes and replace.
Possible Cause:
Liquid carryover into the pump cylinder broke vanes
while pump was running, or oil broke vanes on start-up.
Remedy:
(a) Install condensate trap on the inlet of the pump.
(b) Pump was overfilled with oil in oil reservoir.
Follow oil filling procedure (see Section 1.5) and do not
overfill.
(c) Built-in, anti-suck-back valve (Ref. 250 through
255) leaking while pump was shut down and vacuum
was left in manifold. Clean valve seat and check that
anti-suck-back valve holds vacuum on inlet when pump
is shut down.
(d) Two pumps or a receiver is on the same main
line. Install a manual or automatic operated valve in
front of each pump.
4.8 Trouble
Automotive-type oil filter (Ref. 100) does not
get warm within two to five minutes when
cold pump is started.
Possible Cause:
Automotive-type oil filter is clogged.
Remedy:
Replace automotive-type filter per Section 3.2 and
exchange oil per Section 1.5.
Possible Cause:
Wrong automotive-type filter is used and/or oil lines and
oil coolers leading to pump are clogged.
Remedy:
Use only automotive filter as listed in Section 3.2 and
blow lines free. Flush oil cooler.
Possible Cause:
The oil cooler (Ref. 241) is plugged internally with burnt
These values are taken at an ambient temperature of
68°F. The maximum recommended ambient operating
temperature for an R 5 is 100°F on a continuous basis.
When it is necessary to operate a pump in ambient tem-
peratures above this limit, careful oil monitoring and/or
optional water cooling is necessary. Contact the facto-
ry for details.
Possible Cause:
Not enough air ventilation to the pump.
Remedy:
Clean motor and pump air grills. Do not install the
pump in an enclosed cabinet unless a sufficient amount
of cool air is supplied to the pump. On pumps with oil
cooling coils, clean outside fin assembly. Bring ambient
air temperature down.
Possible Cause:
Automotive-type oil filter clogged and pump does not
receive enough oil.
Remedy:
Change automotive oil filter.
Possible Cause:
Not enough oil in oil reservoir, or badly burned oil is
used for pump lubrication.
Remedy:
Drain and refill only with Busch recommended oil.
Increase oil change intervals.
Note: On some high temperature applications, it may
be necessary to change to a high temperature oil such
as R590 or R570. Contact the factory for recommen-
dations.
4.7 Trouble
Pump is seized.
Possible Cause:
Pump operated without oil and vanes are broken.
Remedy:
Disassemble and exchange vanes as outlined in the
Maintenance and Repair Manual or contact the nearest
Busch Factory Service Center..
Technical Data
Model 0025 0040 0063 0100 0101 0250
Nom. pumping speed (ACFM)
18 26 36 56 71 170
Free air displacement (CFM)
20 28 41 63 77 180
Maximum sound level (dBa)
70 70 70 71 71 81
3 phase motor data (HP*)
1 1/2 2 3 5 5 10
1 phase motor data (HP*)
1 1/2 2 3 5 5 N/A
Approx. oil capacity (qts)
1.4 1.4 2.5 2.7 2.7 7
Inlet connection - NPT (inch)
1 1/4 1 1/4 1 1/4 1 1/4 1 1/4 2
End vacuum - RC (Torr)
15 15 15 15 15 15
End vacuum - RA (Torr)
0.5 0.5 0.5 0.5 0.5 0.5
Approx. weight (lbs)
106 120 172 198 198 460
Notes: *Because various motor types might be available and/or used on your specific pump, you should always refer to the motor nameplate
to verify HP, volts, amps, frame size, etc. or consult the factory.
oil (0250 models).
Remedy:
Remove the oil cooler and flush. Pump may have to be
disassembled completely to correct a severely contam-
inated condition.
5.0 LIMITED STANDARD WARRANTY
Busch, Inc. warrants that all products furnished by it are
free from defects in material and workmanship at the
time of shipment for a period of 18 months from the
date of shipment, or 12 months from the date of instal-
lation, whichever occurs first. Claims must be made
during that period and are limited to the replacement or
repair of parts claimed to be defective.
In the case of components purchased by Busch, Inc.,
such as starters, controls, mechanical seals, motors,
couplings, etc., the warranty of that manufacturer will be
extended to the purchaser in lieu of any warranty by
Busch, Inc. The replacement of wear items including,
but not limited to, seals, bearings, couplings, exhaust
cover gaskets, oil drain plugs, oil fill plugs etc., made in
connection with normal service are not covered by this
Warranty.
The Limited Standard Warranty is valid only when the
product has been properly installed, used in a normal
manner, and serviced according to the operating man-
ual. This warranty shall not extend to products that
have been misused, neglected, altered, or repaired
without factory authorization during the warranty period.
We highly recommend the use of Busch oils and parts
to achieve documented performance and efficient oper-
ation. The use of oils or parts other than Busch could
limit the life expectancy of the equipment and could void
any warranties if they are the cause of any damage.
Operating conditions beyond our control such as
improper voltage or water pressure, excessive ambient
temperatures, or other conditions that would affect the
performance or life of the product will also cause the
warranty to become void.
Permission to return parts for warranty repair must be
obtained, and all returns must be prepaid to the factory.
If, after examination, the product or part is found to be
defective, it will be repaired or replaced on a no-charge
basis and returned, FOB the factory. If it is determined
that the Warranty has not been breached by Busch,
Inc., then the usual charges for repair or replacement
will be made, FOB the factory. Parts or products that
are obsolete or those made to special order are not
returnable.
This Limited Standard Warranty applies only to the
above and is for the period set forth. Busch, Inc.'s max-
imum liability shall not, in any case, exceed the contract
price for the product, part, or component claimed to be
defective; and Busch, Inc. assumes no liability for any
special, indirect, or consequential damages arising
from defective equipment.
THERE ARE NO WARRANTIES IMPLIED OR
EXPRESSED THAT EXTEND BEYOND THOSE
CONTAINED IN THIS LIMITED STANDARD
WARRANTY.
Note: For extended warranties on your new equipment
contact Busch, Inc. Headquarters at 1-800-USA-PUMP.
14
15
Ref Description
1 Cylinder
5 Socket set screw
15 Rotor
18 Bearing sleeve
22 Vane
25 Endplate, motor side
26 Endplate, fan side
30 Bearing
31 Spacer, bearing to Seal
35 Shaft seal
42 Retainer ring
43 Screw, hex head
46 Gasket-ring
47 Plug
49 O-ring
50 O-ring
53 Screw, hex head
54 Lockwasher
57 Hex head screw
58 Lockwasher
60 Taper pin
63 Plug
64 Gasket-ring
65 Shaft key
66 Shaft key
75 Exhaust box
78 Baffle, expanded metal
79 Demister pad
80 Sheet metal baffle
83 Oil sight glass
84 Gasket ring, sight glass
88 Oil fill plug
89 Gasket ring, fill plug
90 Exhaust pressure gauge
95 Oil drain plug
96 O-ring
99 Pipe nipple
100 Oil filter
105 Cover, exhaust box
106 Gasket, exhaust box cover
107 Screw, exhaust box
108 Lockwasher
115 Exhaust filter bracket
120 Exhaust filter
121 O-ring
125 Filter spring assembly
126 Filter spring screw
130 Strainer
136 Gasket, exh. box service block
137 Lockwasher
138 Screw
139 Service block
140 Exhaust cover plate
141 Exhaust cover gasket
142 Socket head cap screw
143 Lockwasher
144 Retaining ring
145 Housing, exhaust port
146 Screw, exhaust housing
148 Service block oil baffle
149 Socket head cap screw
150 Lockwasher
Ref Description
151 Exh. Screen, coarse
152 Exh. Screen, fine
159 Valve assembly, exhaust
161 Oil service block
162 Oil service block gasket
163 Hex head cap screw
164 Lockwasher
165 Socket head cap screw
166 Lockwasher
168 O-ring
169 Exhaust valve cover plate
175 Socket head cap screw
176 Lockwasher
185 Gasket, cylinder/exhaust box
186 Stud
187 Lockwasher
189 Stud
190 Lockwasher
191 Nut
205 Exhaust cover side plate
206 Cover plate gasket
207 Socket head cap screw
208 Lockwasher
221 Hydraulic fitting banjo
222 Hydraulic fitting, straight
223 Hydraulic fitting, elbow/banjo
224 Pipe adapter
225 Hydraulic fitting
230 Oil tubing
231 Oil tubing
232 Oil tubing
238 Socket head cap screw
239 Lockwasher
241 Oil cooler
242 O-ring
244 Fan cover
247 Socket head cap screw
250 Housing, lower, inlet
251 Valve plate, inlet
252 Valve plate guide
253 O-ring
254 Spring, valve plate
255 O-ring
260 Inlet flange, upper
261 Inlet screen
265 Screw, hex head cap
266 Lockwasher
270 Plug
271 Gasket ring
275 Oil return valve
276 Gasket ring
284 Hydraulic, fitting banjo
285 Screw, oil recirculation
286 Banjo fitting housing
288 Gasket ring
289 Screw
290 Oil return line, RA version
291 Hyd. fitting, straight
292 Carburetor jet
293 Oil return line, RC version
297 Screen fan guard
300 Motor mounting bracket
Ref Description
301 Screw hex head cap
302 Lockwasher
306 Motor adapter flange
307 Lockwasher
311 Coupling half, pump side
312 Coupling insert
313 Coupling half, motor side
315 Plastic clip
320 Spacer
321 Fan
322 Axial fan
323 Socket set screw
326 Retainer ring
331 Set screw
333 Set screw
340 Fan guard
341 Screw, self tapping
342 Sleeve, plastic
345 Fan cover shield
353 Socket head cap screw
360 Lockwasher
390 Eye bolt adapter
391 Eye bolt
392 Lockwasher
393 Hex head screw
400 Motor
401 Screw, hex head cap
402 Lockwasher
409 Motor foot spacer
411 Flat Washer
413 Slotted set screw
415 Screw, hex. head cap
416 Stud, motor foot
417 Set screw
419 Spacer, motor foot
421 Foot, rubber
422 Foot, rubber
423 Lockwasher
424 Hex nut
425 Stud
430 Name plate
431 Label "arrow"
436 Maintenance label
440 Gas Ballast Assembly
470 Hyd. fitting banjo
471 Tubing, gas ballast
472 Valve, check gas ballast
473 Coupling
474 Filter, gas ballast
475 Valve, pet cock
476 Gas ballast elbow
477 Pet cock valve
478 Hex head cap screw
479 Lockwasher
Note: This parts list includes parts for all
the pumps covered by this manual.
Your specific model might not neces-
sarily have all the part5 indicated in this
list. Refer to the illustration for your
specific model pump when comparing
part numbers or consult the factory.
0025 - 0250 "C" & "E" Parts List
16
17
/0101
18
Busch Inc. Factory Service Centers
California Illinois
13826 Struikman Road 430 Windy Point Drive
Cerritos, CA 90703 Glendale Heights, IL 60139
Phone (562) 926-8422 Phone (630) 545-1310
Fax (562) 926-7262 Fax (630) 545-1384
New Jersey Puerto Rico
39 Davis Street 420 E Street, Suite 4
South Plainfield, NJ 07080 Minillas Industrial Park
Phone (908) 561-3233 Bayamon, PR 00959-1901
Fax (908) 561-3909 Phone (787) 798-5045
[email protected] Fax (787) 798-5033
Texas Virginia
15411 Vantage Pkwy W., Suite 216 516 Viking Drive
Houston, TX 77032 Virginia Beach, VA 23452
Phone (281) 449-2381 Phone (757) 463-7800
Fax (281) 449-2383 Fax (757) 463-7407
19
P/N 0872.900.823
Revision 03/05
Busch, Inc.
516 Viking Drive
Virginia Beach, Virginia 23452
Phone: (757) 463-7800
FAX: (757) 463-7407
