0872.929.551 (I-O Manual R 5 0165-0305 D, 0.1 mbar, 0416).qxp

Installation and

Operating Instructions

Rotary Vane Vacuum Pumps

R 5 RA 0165, 0205, 0255, 0305 D

0.1 mbar versions

Busch LLC

516 Viking Drive

Va. Beach, VA 23452

Phone: (757) 463-7800

Fax: (757) 463-7407

P/N 0872.929.551 / 0416

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TABLE OF CONTENTS

GENERAL

Identification

Operating Principles

1.0 INSTALLATION

1.1 Unpacking

1.2 Location

1.3 Power Requirements

1.4 Vacuum Connections

1.5 Oil Filling

2.0 OPERATION

2.1 Start-up

2.2 Gas Ballast

2.3 Process Gas

2.4 Stopping Pump

2.5 Water-Cooled Pumps (optional)

2.6 Oxygen Service Pumps

3.0 MAINTENANCE

3.1 Pump Oil

3.1.1 Oil Level

3.1.2 Oil Type and Quantity

3.1.3 Oil and Filter Change

3.1.4 Oil Flushing Procedure

3.2 Automotive-Type Oil Filter

3.3 Exhaust Filter

3.4 Inlet Flange

3.5 Vacuum Inlet Filter (Optional)

3.6 Maintenance Chart

3.7 Overhaul Kit/Filter Kit

4.0 TROUBLESHOOTING

5.0 LIMITED STANDARD WARRANTY

Technical Data

Parts List

Exploded View Drawing

Page

We reserve the right to change the product at any time without any form of notification. The information in this

publication is accurate to the best of our ability at the time of printing. Busch LLC will not be responsible for errors

encountered when attempting to perform tasks outlined in this publication which is copyright protected.

GENERAL

Identification

For model identification, see the nameplate mounted

on the side of the exhaust box.

This manual is written to cover installation and opera-

tion of the RA pump models 0165, 0205, 0255 and

0305 with a "D" appearing as the seventh character in

the model type number stamped into the nameplate.

For example it would appear as follows:

RA0XXX - D

XXX - XXXX

When ordering parts, it is helpful to include the

identification code stamped into the side of the cylinder

as well as the serial number from the nameplate.

Operating Principles

All reference (Ref. XX) numbers listed in the text and on

illustrations throughout this manual are related to the

drawings and parts list near the end of this publication.

R 5 Series, Single Stage, Rotary Vacuum Pumps are

direct-driven, air-cooled, oil-sealed rotary vane pumps

which operate as positive displacement pumps. They

consist of a rotor positioned eccentrically in a

cylindrical stator (see Fig. 1). When the rotor spins,

centrifugal force pushes the vanes, which glide in 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.

Differential pressure constantly causes oil to be

pressed into the compression chambers. The gas/oil

mixture is separated by the discharge filters (Ref. 120).

The oil-free medium is discharged through the exhaust

cover plate (Ref. 140) to atmosphere. This operation is

repeated three times each revolution.

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 LLC Engineering (see Section 2.2 -

Gas Ballast). When you desire to use the pump on an

air stream that contains vapors, contact Busch LLC

Engineering for operating recommendations;

otherwise, the warranty could be void.

1.0 INSTALLATION

1.1 Unpacking

Inspect the box and pump carefully for any signs of

damage incurred in transit. R 5 Pumps pass a rigorous

operating test in the factory and are packed carefully to

avoid transit damage. Since all pumps are ordinarily

shipped FOB our factory, such damage is the normal

responsibility of the carrier and should be reported to

them.

Remove any nuts from the bottom of the box/crate and

pull the pump out of the container using a suitable lifting

device and the lifting eye bolt (Ref. 391). Then,

unscrew any remaining studs that secured the bottom

of the rubber feet to the bottom of the crate.

The inlet port of the pump is covered with a plastic cap

prior to shipment to prevent dirt and other foreign

material 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. To allow for proper cooling, there must

be a minimum 20 inches of clearance for the oil cooler

(Ref. 241) and motor fan (axially). The left and right side

of the pump require a minimum 8 inches of clearance.

Adequate ventilation must be provided. 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.

Fig. 1 - Front of the R 5 RA 0255 D Pump

The motor must be connected according to the

electrical 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.

1.4 Vacuum Connections

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. Drain the drip leg often to prevent

condensation from entering the pump. Also, when

installing discharge piping, a drip leg should be

installed.

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).

The type and size of the inlet connections of the R 5

Series pump is shown in the TECHNICAL DATA page

13.

If the gas that is pumped contains dust or other foreign

solid particles, a suitable (10 micron rating or less) inlet

filter 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,

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).

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 temperatures, and will prolong the life of

Fig. 2 - Basic R 5 RA 0165, 0205, 0255, and 0305 D Series Pump

CAUTION: Do not use the anti-suck-back valve as

a check or shut-off valve for your vacuum system.

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.

88 83 95 194 22 15 100 Oil

75 159 260 120 140

Inlet

Exhaust

exhaust filter elements. This oil can be obtained

directly from Busch LLC in Virginia Beach, Virginia.

The strict use of Busch oils and parts from the day of

purchase can extend the life of the vacuum pump.

For general applications, use R530. 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. Contact the

factory for recommendations when using other oils.

The TECHNICAL DATA chart on page 13 gives the

approximate quantity of oil required. 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), and pressure gauge

(Ref. 88), making sure that the gasket (Ref. 89) is in

place and properly seated and secured. 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.

2.2 Gas Ballast

R 5 Series RA 0165 through 0305 D pumps are

equipped with an adjustable gas ballast valve (Ref.

470-480). The adjustable gas ballast valve should nor-

mally 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.

Check the gas ballast filter periodically to ensure that air

is flowing through it properly.

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

prevent the pump from rotating backwards when it is

shut off.

Install a manual or automatic valve or check valve in

each pipe leading to each pump when multiple pumps

are pumping on a common header.

All R 5 Series pumps are vented internally to

atmospheric pressure through venting holes which 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

circulation 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 thermostatically activated valve (see

Fig. 3) 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 setpoint and close at approximately 3°F

to 5°F below the set point. The valve set point is

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!

CAUTION: Do not use the anti-suck-back

valve as a check or shut-off valve for your

vacuum system.

adjustable as follows:

(a) Rotate the valve adjustment screw counterclockwise

to cause the valve to open at a higher temperature.

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.

Fig. 3 - Water Cooled Pump

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

applications. Contact Busch Engineering in Virginia

Beach for details.

2.6 Oxygen Service Pumps

Oxygen service pumps must be used in oxygen

enriched applications that are defined as any

application which has a process gas that is 25% or

more oxygen. If this pump is contaminated by organic

compounds 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

assembled 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 damage might occur.

It is mandatory that these operating instructions be

read and understood prior to vacuum pump

installation and start-up!

For overhaul/repair of oxygen service pumps,

Busch LLC 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 MAINTENANCE

R 5 Series, Single Stage, Rotary Vacuum Pumps

require very little maintenance; however, to insure opti-

mum pump performance, the following 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 (see Section1.5).

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.

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

sufficient 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

necessary to add or drain oil from the pump between

recommended 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

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 Y LVAC 25/6

• 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.

CAUTION: Do not add oil while the pump is running

since hot unfiltered oil vapor may escape through

the oil fill port.

WARNING: Insufficient oil quantity in the pump has

the potential, under certain conditions, to lead to

self-ignition of the remaining oil in the pump.

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 open, 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 required. Contact the factory

for flushing oil (Busch R568) and instructions.

3.1.2 Oil Type and Quantity

See Section 1.5 and the Technical Data page 13 for

details on oil type and quantity.

3.1.3 Oil and Filter Change

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. Oil must

be changed after the first 100 initial hours of operation.

After the initial oil change, and 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

significantly extend the operating hours between oil

changes; however, you may need to flush out the pump

before changing. Contact the factory Service

Department for advice or refer to Section 3.1.4 for the

flushing procedure.

To change the oil, the pump must be switched off and

ventilated to reach atmospheric pressure. Remove the

oil drain plug (Ref. 95) and drain the oil. Dispose of the

oil in compliance with local or national regulations.

When the oil stops draining, replace the oil drain plug.

Start the pump again for a few seconds. Stop the pump

once again, and then reopen the drain plug and

discharge any remaining oil.

Refasten the oil drain plug. Remove the oil filter

(Ref.100) and replace it with a new one using a Busch

genuine oil filter. Make sure to tighten the filter

securely against the aluminum sealing surface so that

leaks will not occur.

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

relatively low number of operating hours. The higher

the temperature, the quicker the oil becomes

contaminated. If the oil temperature is too severe,

Busch R570 or R590 synthetic oil should be used to

withstand the elevated temperatures. When changing

to synthetic oil, the pump should be flushed with Busch

R568 oil. Contact the factory for instructions on the

flushing procedure. Auxiliary oil cooling is the most

practical approach to a severe heating problem.

Contaminated Air Stream

When the air stream contains solids and/or liquid that

contaminate the oil, the oil must be changed more

often. If the air stream contains a small percentage of

contaminates 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 are more than slightly aggressive

must use a chemical duty pump.

Oil change intervals can only be established by

experience 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 carbonized 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

overhauled.

To help determine if flushing is needed, observe the

condition of the oil as it is drained from the pump. Is it

CAUTION: When changing the oil and filters, 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

radiators and cooling coils, can cause mechanical

damage or extreme overheating which could cause

the oil vapors to ignite.

WARNING: Always take the necessary precautions

concerning personal protective equipment when

changing oil and make sure the pump is switched

to the "off" so that accidental starting will not

occur. Oil temperature can reach 212°F and may

pose a danger of scalding.

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

synthetic oil.

All of the oil will be removed and replaced with the

flushing oil (Busch R568), and eventually that will be

replaced by whatever Busch oil is needed for your

particular 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 complete 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

contaminated 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

filter or filters until after the flushing to prevent

contamination 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

operating conditions closely. Check for noise,

overheating and oil condition until a regular oil change

schedule can be established.

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

prevent 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

filter, use only a Busch genuine filter.

Note: Make sure to tighten the Busch oil filter

securely against the aluminum sealing surface so that

leaks will not occur.

3.3 Exhaust Filter

Exhaust filters (Ref. 120) should be checked monthly. A

pressure gauge (Ref. 88) 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

pressure in the red field (for a continuos period of time)

requires an immediate change of the exhaust filter(s).

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.

WARNING: Always wear safety glasses and other

appropriate personal protective equipment when

performing any maintenance or repair to your R 5

pump.

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 replacement operation.

It is only necessary to change the filters when the

elements become clogged with foreign material or

burned oil. Indications of clogged filters are smoke and

oil mist coming from the pump exhaust or higher than

normal motor current.

In order to replace the exhaust filters, unscrew the

screws and washers (Ref. 142/143) from the exhaust

cover plate (Ref. 140). Remove the cover plate and

gasket (Ref. 141).

Remove the distance pin (Ref. 137), the baffle strainer

(Ref. 130) and the sheet metal plate (Ref. 136).

Remove the discharge filter assembly by unscrewing

the nut (Ref. 134) and removing the lock washer (Ref.

132). Carefully slide the assembly out of the exhaust

box (Ref. 75). Stand the filter assembly up on a clean

flat surface.

To have access to the individual filters, unscrew the two

cylinder cover screws (Ref. 126), and remove the two

lock washers (Ref. 128) and the exhaust filter grip plate

(Ref. 115).

Remove the exhaust filters (Ref. 120) and O-rings

(Ref.121). Remove the filter support (Ref. 118) and

O-rings (Ref. 119).

Replace the support and O-rings with new ones. Make

sure that the O-rings are fitted securely and that the

filter elements (Ref. 120) fit securely into the

depressions on the filter support (Ref. 118). The

indicating arrow on each element must be pointing

upward toward the top of the exhaust box after the

assembly has been installed.

Carefully position the filter support tube (Ref. 133)

between the exhaust filter bracket (Ref. 115) and the

filter support without displacing the filters from their

seated position in the filter support. Install the two lock

washers (Ref. 128) and two screws (Ref. 126).

Insert the support and filter assembly into the exhaust

box using the stud (Ref. 131) as a guide. The stud

should slide through the hole in the support (Ref. 133).

Secure the assembly with the lock washer (Ref. 132)

and hexagon nut (Ref. 134).

Reinstall the sheet metal plate (Ref. 136) and the baffle

strainer (Ref. 130) into the guide track of the exhaust

box (see Fig. 3). Press to the bottom of the exhaust

box. Make sure that the baffle strainer touches all sides

of the exhaust box. Insert the distance sleeve (Ref.137)

into the two grooves. This holds the sheet metal plate

Fig. 4 - Exhaust Filters and Strainer

and baffle strainer in place.

Inspect the exhaust box end cover gasket (Ref. 141) for

damage and replace if damaged. With the gasket in

place, secure the exhaust cover end plate (Ref. 140) to

the exhaust box using eight hex head cap screws

(Ref.142) and eight lock washers (Ref. 143).

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, which is

the 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 as described previously.

3.4 Inlet Flange

The standard inlet flange assembly contains an inlet

screen (Ref. 261) which may require occasional

cleaning. 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 filter is offered and can help minimize the

need or frequency 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

CAUTION: Excessively contaminated and/or

clogged exhaust filters could possibly lead to

elevated pump temperatures which could, under

certain circumstances, cause the lubricating oil to

self-ignite.

(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 lock wash-

ers. 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 an optional special

vacuum inlet filter 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 particles to which the pump is

exposed.

To clean the inlet filter, unsnap the lid clamps or remove

the knobs and lift off the filter lid. Remove cartridge,

being careful not to knock any foreign particles present

inside the canister into the pump suction. Clean foreign

particles from the canister with an air hose, and

carefully back flush the filter cartridge with shop air. If

the filter cartridge has been subjected to moisture or is

extremely dirty it may need replacement.

3.6 Maintenance Chart

Note: 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 Section 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 3.2).

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

filter material as practice determines.

As necessary: The radiator (Ref. 241), fan hood (Ref.

244) and motor cover should be inspected regularly for

debris. Soiling prevents cool air intake and may lead to

overheating of the pump.

3.7 Overhaul Kit/Filter Kit

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, automotive type oil

filter, exhaust filter and synthetic baffle strainer is

available 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

The 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 by far the most

common cause of not reaching the ultimate pressure.

Remedy: Shut off the pump, after the operating

temperature has been reached, drain the warm oil from

pump and exchange the automotive-type oil filter, if

necessary. Flush and fill the pump with new oil and

take a new "blank-off” measurement after operating

temperature is reached (at least 20-30 minutes).

Possible Cause: The vacuum system or vacuum

piping is not leak-tight.

Remedy: Check the hose and pipe connections for

possible leak.

Possible Cause: The wire mesh inlet screen is

plugged (Ref. 261).

Remedy: Clean the wire mesh inlet screen. Install an

inlet filter if the problem repeats frequently.

Possible Cause: No oil or not enough oil in the oil

reservoir.

Remedy: Shut off the pump, add the necessary oil, or

if oil seems contaminated, drain the balance of the oil

from the pump, exchange the automotive oil filter, and

refill with fresh oil. Flush if necessary.

Possible Cause: The automotive-type oil filter is dirty

or clogged .

Remedy: Replace the automotive-type oil filter,

exchange the oil, if necessary, and refill with fresh oil.

Possible Cause: The inlet anti-suck-back valve plate

(Ref. 251) is stuck in closed or partially open position

due to contamination.

Remedy: Disassemble the inlet valve and screen.

Clean as required.

Possible Cause: The oil tubing fittings are loose and

leaking.

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.

Remedy: Contact the nearest Busch Factory Service

Center for instructions.

Possible Cause: Vanes are blocked in rotor or are

otherwise damaged.

Remedy: Free vanes or replace with new ones.

Contact the nearest Busch Factory Service Center for

instructions.

Possible Cause: The radial clearance between the

rotor and cylinder is no longer adequate.

Remedy: Contact the nearest Busch Factory Service

Center for instructions.

Possible Cause: The internal parts are worn or

damaged.

Remedy: Contact the nearest Busch Factory Service

Center for instructions.

Possible Cause: The inlet filter is clogged due to

process material.

Remedy: Contact the factory for recommendation on

proper filter cartridge.

4.2 Trouble

Pump will not start.

Possible Cause: The motor does not have the proper

supply voltage or is overloaded; the motor starter

overload settings are too low or are the wrong setting;

fuses are burned; or the wire is too small or too long,

causing a voltage drop at the pump.

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 the ambient temperature is

high, use larger size overloads or adjust the setting 5%

above nominal motor nameplate value.

Possible Cause: The pump or motor is blocked.

Remedy: Remove the fan cover and try to turn pump

and motor by hand. If frozen, remove the motor from

the pump and check the motor and the pump

separately. If the pump is frozen, contact the nearest

Busch Factory Service Center for instructions.

4.3 Trouble

The pump starts, but labors and draws a very high

current.

Possible Cause: The oil is too heavy (viscosity too

high) or the ambient temperature is below 5 degrees C

(41°F).

Remedy: Change to R580 vacuum oil if very cold, or

warm up the oil before filling.

Possible Cause: Pump is running in the wrong

direction.

Remedy: Check for the 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: The pump is over filled with oil or the

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 the exhaust filters, maintain proper

oil condition, oil level, and use only Busch

recommended vacuum oil and filters.

Possible Cause: Loose connection in motor terminal

box; not all motor coils are properly connected. The

motor operates on two phases only.

Remedy: Check the motor wiring diagram for proper

hookup, especially on motors with six internal motor

windings, tighten and/or replace loose connections.

Possible Cause: Foreign particle in pump, vanes

broken, bearings seized.

Remedy:Contact the nearest Busch Factory Service

Center for instructions.

4.4 Trouble

Pump smokes at the exhaust side or expels oil

droplets from the exhaust.

Possible Cause: Inlet to pump is in a wide open

condition.

Remedy: Do not operate pump at high inlet pressures

for more than a few minutes (pressures = 0.00-10.0" Hg

vac.)

Possible Cause: The exhaust filter is not properly

seated with the O-ring (Ref. 121) in filter base or the

filter material is cracked.

Remedy: Check the condition and check for proper

seating of the exhaust filters. Replace if necessary.

Also, check the filter spring clips for tightness.

Possible Cause: The exhaust filter is clogged with

foreign particles.

Remedy: Replace the exhaust filter.

4.5 Trouble

Pump runs very noisily.

Possible Cause: Coupling insert is worn.

Remedy: Replace the coupling insert in motor/pump

coupling.

Possible Cause: Bearing noise.

Remedy: Contact the nearest Busch Factory Service

Center for instructions.

Possible Cause: Vanes stuck.

Remedy: Contact the nearest Busch Factory Service

Center for instructions. Use only the recommended

Busch oil and change oil more frequently.

4.6 Trouble

The pump runs very hot.

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.

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

temperatures above this limit, careful oil monitoring

and/or optional water cooling is necessary. Contact the

factory at Virginia Beach for details.

Possible Cause: Not enough air ventilation to the

pump.

Remedy: Clean the motor and pump air grills. Clean

the radiator. Do not install the pump in an enclosed

cabinet unless a sufficient amount of fresh air is

supplied to the pump. Bring the ambient air

temperature down.

Possible Cause: The automotive-type oil filter clogged

and pump does not receive enough oil.

Remedy: Change the automotive oil filter.

Possible Cause: Not enough oil in oil reservoir or badly

burned oil is used for pump lubrication.

Remedy: Drain and refill the pump only with

non-detergent oil and increase oil change intervals.

Note: On some high temperature applications, it maybe

necessary to change to a high temperature oil such as

R590 or R570. Contact the factory for

recommendations.

4.7 Trouble

Pump is seized.

Possible Cause: The pump operated without oil and

vanes broke.

Remedy: Contact the nearest Busch Factory Service

Center for instructions.

Possible Cause: The pump was operated for an

extended period of time in the wrong rotation.

Remedy: Inspect vanes and replace. Contact the

nearest Busch Factory Service Center for instructions.

Possible Cause: Liquid carry over into the pump

cylinder broke vanes while pump was running, or oil

broke vanes on start-up.

Remedy: Install a condensate trap on the inlet of the

pump. Or, pump was over filled with oil in oil reservoir.

Follow oil filling procedure (see Section 1.5) and do not

overfill. Or, the built-in anti-suck-back valve (Ref. 250

through 255) is leaking while pump was shut down and

vacuum was left in manifold. Clean the valve seat and

check that anti-suck-back valve holds vacuum on inlet

when pump is shut down.

4.8 Trouble

The automotive-type oil filter (Ref.100) does not get

warm within two to five minutes when cold pump is

started.

Possible Cause: The automotive-type oil filter is

clogged.

Remedy: Replace the automotive-type filter per

Section 3.2 and exchange oil per Section 1.5.

Possible Cause: The wrong automotive-type filter is

used and/or oil lines 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 is plugged internally

with burnt oil.

Remedy: Remove oil cooler and flush. Pump may

have to be disassembled completely to correct a

severely contaminated condition.

5.0 LIMITED STANDARD WARRANTY

Busch LLC 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

installation, 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 LLC,

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 LLC. 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

manual. 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

operation. 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 LLC

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 return-

able.

This Limited Standard Warranty applies only to the

above and is for the period set forth. Busch LLC'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 LLC 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.

TECHNICAL DAT

Model 165 205 255 305

Nominal pumping speed ACFM 115 130 170 196

Ultimate Pressure torr 0.075 0.075 0.075 0.075

Nominal motor rating HP 7.5 7.5 10 12

Nominal motor speed RPM 1800 1800 1800 1800

Sound level (ISO 2151) dB(A) 72 74 74 76

Oil capacity Qts 7 7 7 7

Gas inlet / outlet NPT 2" / 2” 2" / 2” 2" / 2” 2" / 2”

Approximate weight lbs 445 445 515 515

Parts List for 0165-0305 D

Ref Description

140 Exhaust cover plate

141 Exhaust cover gasket

142 Hex head cap screw

149 Socket head cap screw

159 Exhaust valve

162 O-ring

169 Exhaust valve cover plate

171 Oil tube insert

175 Socket head screw

185 Gasket

189 Stud

191 Hex nut

194 Oil return float valve complete

195 Oil return float valve mount

196 Socket head cap set screw

197 O-ring

198 Socket head cap screw

205 Side cover plate

206 Side cover plate gasket

207 Socket head cap screw

222 Hyd. fitting, elbow

223 Hyd. fitting, elbow

225 Hyd. fitting, banjo

228 Hyd. fitting, couplng

229 Hyd. fitting, straight

230 Oil tubing

231 Oil tubing

232 Oil tubing

235 Hydraulic fitting, straight

238 Socket head cap screw

239 Lock washer

241 Oil cooler

242 O-ring

244 Fan cover

247 Socket head cap screw

250 Lower inlet flange

251/2/4 Anti-suckback valve

253 O-ring

255 O-ring

260 Upper inlet flange

261 Inlet screen

265 Hex head cap screw

266 Lock washer

270 Hydraulic fitting, elbow

290 Teflon tubing

291 Hydraulic fitting, elbow

300 Motor bracket

301 Hex head cap screw

302 Lock washer

306 C-face adapter flange

307 Socket head cap screw

311 Coupling half, motor side

312 Coupling insert

313 Coupling half, pump side

319 Motor spacer

321 B-side fan

Ref Description

0 Module

1 Cylinder

5 Plug, screw

6 Socket pipe plug

15 Rotor

18 Shaft seal sleeve

22 Vane

25 Endplate, motor side

26 Endplate, fan side

30 Roller bearing

31 Endplate spacer

35 Shaft seal

42 Shaft seal retaining plate

43 Screw, hex head

49 O-ring

50 O-ring

53 Hex head screw

54 Lock washer

57 Socket head cap screw

58 Lock washer

60 Taper pin

61 Parallel pin

65 Shaft key

66 Shaft key

75 Exhaust box

80 Sheet metal baffle

83 Oil sight glass

84 Sight glass gasket

85 Socket head plug

87 Oil fill elbow

88 Oil fill plug

89 Ring gasket

90 Fill plug with gauge

90.1 Exhaust pressure gauge

92 Socket head plug

95 Oil drain plug

96 O-ring

99 Nipple

100 Oil Filter

105 Front cover plate

106 Front cover plate gasket

107 Socket head cap screw

115 Exhaust filter bracket

118 Exhaust filter mount

119 O-ring

120 Exhaust filter

126 Socket head screw

127 Distance rod

128 Lock washer

130 Baffle strainer

131 Stud

132 Flat washer

133 Exhaust filter support tube

134 Hex nut

136 Baffle strainer screw

137 Distance sleeve

Ref Description

322 A-side fan

326 Fan retaining ring

353 Socket head cap screw

360 Lock washer

390 Eyebolt adapter

391 Eyebolt

392 Lock washer

393 Hex head cap screw

400 Motor

401 Hex head cap screw

402 Lock washer

417 Socket head cap screw

421 Rubber foot

422 Rubber foot

431 Directional arrow label

436 Pump label

470-80 Gas ballast assembly

488 Plug with seal

492 Screw plug

496 Socket head plug

498 Plug with seal

530 B-side fan spacer

9000 Socket head plug

9013 Plug

Fig. 5 - Exploded View Drawing

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