Eaton Vickers VT16 User manual

M-1538-SRevised 3/1/75
Power Steering Pumps
VT16 & VT17 Series
Overhaul Manual
Vickers®
Steering

2
Table of Contents
Section Page
I. Introduction 3
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A. Purpose of Manual 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B. General 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 1. Installation Drawings and Parts Catalog Chart 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. Physical and Operating Characteristics 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 2. Model Code Breakdown 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
II. Description 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A. General 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B. Assembly and Construction 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. Flow Control and Relief Valve 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1. 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D. Application 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
III. Principles of Operation 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A. General 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B. Pumping Cartridge 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. Hydraulic Balance 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2. Schematic View 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 3. 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D. Flow Control and Relief Valve 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 4. 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
IV. Installation and Operating Instructions 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A. Drive Connections 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B. Shaft Rotation 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. Hydraulic Tubing 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D. Hydraulic Fluid Recommendations 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3. Model Code Breakdown 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E. Overload Protection 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
F. Operating Instructions 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
V. Service Inspection and Maintenance 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A. Service Tools 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B. Inspection 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. Maintenance 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D. Lubrication 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E. Trouble Shooting 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3. Trouble Shooting Chart 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
F. Spare Parts 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VI.Overhaul 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A. Disassembly 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 5. 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B. Inspection, Repair and Replacement 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. Re-assembly 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VII.Testing of VT16 and VT17 Pumps 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3
Section I - Introduction
A. Purpose of Manual
This manual is issued as the service publication for Vickers
VT16 and VT17 series Power Steering Pumps. Pumps are
identified by a model code on the nameplate as belonging to
the series of models covered by the model code in Table 2.
B. General
Operation, maintenance and overhaul information for the
models covered by Table 2 is contained in this manual. Parts
ordering information and installation dimensions are not
included. Parts catalog and installation drawing numbers are
listed in Table 1.
Model
Series Installation Drawing Parts Catalog
VT16
VT17 M166357 M166358 M-1370-S
Table 1.
C. Physical and Operating
Characteristics
Vickers VT16 and VT17 Pumps are primarily used to supply
hydraulic fluid flow for the operation of power steering
systems. These are balanced vane type, positive
displacement pumps with a constant rate of delivery per
revolution. The direction of pump rotation can be changed to
suit specific applications. Pumps are available with an
integral reservoir or with a manifold for remote reservoir
locations.
7Design
8
5Relief Valve Setting
75 - 750 PSI
95 - 950 PSI
120 - 1200 PSI
Controlled Flow Rate
15 - 1.5 GPM
25 - 2.5 GPM
30 - 3.0 GPM
40 - 4.0 GPM
50 - 5.0 GPM
1
345 761 2
6
2
3
Vane Type Steering Pump
Manifold And Reservoir
16 - Reservoir
17 - Manifold
Series
Optional Left Hand Rotation
Table 2. Model Code Breakdown.
4Ring Capacity
15 - 1.5 GPM
40 - 4.0 GPM
8

4
Section II - Description
A. General
The VT16 and VT17 series pumps are identical in basic op-
eration and performance characteristics. Differences in the
individual units are covered by variables in the model num-
bers illustrated in Table 2. Service inquiries and parts orders
should always include the complete model number, which
can be found on the pump nameplate.
B. Assembly and Construction
1. The assembly and construction of the VT16 series
pumps are illustrated in cutaway in Figure 1. The unit con-
sists principally of a body, cover, ring, rotor, vanes, pressure
plate, relief valve sub-assembly, driveshaft and reservoir.
The vanes are contained in the rotor slots and follow the
cam shaped contour of the ring as the rotor is driven in rota-
tion by the driveshaft. Fluid flow is developed by the vanes
carrying fluid around the ring contour.
2. The VT17 series is identical to the VT16, except that
in place of the reservoir, the VT17 is equipped with a man-
ifold. The manifold contains a loop circuit passage for oil
from the pressure side of the pump to the inlet. It also pro-
vides oil line connections to the reservoir located elsewhere
in the circuit.
C. Flow and Control and Relief Valve
The integral flow control and relief valve limits the fluid flow
to the system to a prescribed rate. Volume greater than the
rated flow is by-passed to the pump inlet. The relief valve
limits the maximum pressure in the circuit.
Flow
Control
Valve
Figure 1.
Pressure
Plate
Ring
Vane
Rotor
Shaft
Body
Cover
Reservoir
D. Application
Pump ratings, methods of installation and application in-
formation should be obtained from Vickers.
Section III - Principles of Operation
A. General
These units depend on the vehicle engine as a source of
rotary mechanical power to produce fluid flow. Inlet flow is
created by a decreased pressure set up by the action of the
pumping cartridge. Flow is directed through the cartridge to
the pressure port and monitored by the flow control and relief
valve.
B. Pumping Cartridge
The pump cartridge consists principally of a ring, rotor and
vanes (see Figure 2). The rotor is driven within the ring by a
drive shaft, coupled to the power source. Radial movement
of the vanes, and the rotation of the rotor, cause the cham-
ber area between vanes to increase in size at the inlet (large
diameter) section of the ring. This results in a low pressure,
or vacuum in the chamber. This pressure differential forces
oil to flow into the inlet chamber by atmospheric pressure.
Oil is then trapped between the rotating vanes and is forced,
through porting in the pressure plate, to the outlet and into
the system as the chamber size decreases at the pressure
quadrants (small diameter) section of the ring. System pres-
sure fed under the vanes assures sealing contact of the
vanes against the ring during normal operation.
C. Hydraulic Balance
The ring is shaped so that two pumping chambers are
formed 180°apart. Thus, any hydraulic loads on the bear-
ings are cancelled.

5
Figure 2. Schematic View Showing Oil Flow and Vickers Hydraulic Balance Construction.
Cam Ring Inlet
Outlet
Outlet
Rotor
Drive Shaft Inlet
Rotation
Vane
Outlet
Inlet
Rotation
Figure 3.
H
F
2
G
43EDB
A
C
1J
D. Flow Control and Relief Valve
1. Maximum fluid delivery and maximum system pres-
sure are determined by the integral flow control and relief
valve (Figure 3). The rate of flow depends on the sizes of the
restriction (D) in the cover. Excess oil is ported past the slid-
ing spool (1) to the return circuit by way of passage C.
2. When all pump delivery can pass through the restric-
tion to the load, the spool is held in the closed position by the
large spring (2) and passage C is blocked from chamber B.
This is the condition illustrated in Figure 4-A.
3. When pump delivery is greater than the flow rate de-
termined by the restriction (D), a pressure build-up in cham-
ber B forces the spool open against the large spring force.
Excess fluid is throttled past the spool to passage C and
back to inlet, as shown in Figure 4-B.
4. Figure 4-C shows the condition when pressure in the
system builds up to the relief valve setting. Pressure is trans-
mitted through sensing orifices G and H and forces the ball
(4) from its seat. Fluid flow is then from chamber B, through
orifice D, passage E, orifices G, H and J to passage C and to
inlet. The pressure drop across restriction D resulting from
this flow causes a differential pressure on the spool ends
and the spool is shifted against the large spring, permitting
the remainder of pump delivery to flow from chamber B to
passage C.
5. A second function of the valve sub-assembly and #2 is
to hold the pressure plate against the pump cartridge until
pressure builds up in chamber B.

6
Figure 4.
A
All Pump
Delivery
B
Normal Operation C Operation causing excessive
pressure build-up
To Tank
Return
Port
Pressure
Port
Pressure
Code:
Return
Normal
From
Pump
To Tank
Return
Port
Pressure
Port
Pressure
Code: Return
Normal
From
Pump
Pressure
Port
Return
Port
To Tank
From
Pump
Return
High
Pressure
Code:
Section IV - Installation and Operating Instructions
A. Drive Connections
Care must be exercised in pump mounting to insure correct
alignment with the driving medium. If indirect drive is used,
belts and pulleys must be properly aligned and adjusted to
prevent undue side loads being imposed on the shaft
bearings.
B. Shaft Rotation
1. Pumps are manufactured for either right hand or left
hand rotation. They must be driven in the direction of the
arrow on the pump ring or severe damage may result.
2. The direction of rotation can be changed by reversing
the pump ring and replacing the pressure plate with the cor-
rect plate for the desired direction of rotation (see parts cata-
log M-1370-S). Correct disassembly and assembly proce-
dures are given in Section VI of this manual.
C. Hydraulic Tubing
1. The number of bends in tubing must be kept to a mini-
mum to prevent excessive turbulence and friction of oil flow.
2. Tubing must not be bent too sharply. The minimum
radius for bends is three times the inside diameter of the
tube.
3. To minimize flow resistance and the possibility of leak-
age, only as many fittings and connections as are necessary
for proper installation should be used.
4. Tubing must not be sprung into position or undue
strain will result at the connections.
5. All tubing must be thoroughly cleaned before installa-
tion to remove dirt, rust and scale. Recommended methods
of cleaning are sand blasting, wire brushing and pickling.
D. Hydraulic Fluid Recommendations
1. Oil Type - Oils used in hydraulic systems perform the
dual function of lubrication and transmission of power. Oil
must be selected with care and with the assistance of a
reputable supplier.
Crankcase oils meeting or exceeding the ”Five Engine Test
Sequence” for evaluating oils for API (American Petroleum
Institute) service MS (Maximum Severity) best serve the
needs of mobile hydraulic systems. These engine sequence
tests were adopted by the Society of Automotive Engineers,
American Society for Testing Materials, and automotive
engine builders. The MS Classification is the key to selection
of oils containing the type of compounding that will extend
the operating life of the hydraulic system. Oils meeting
Diesel engine requirements, DG and DS classifications, may
or may not have the type of compounding desired for high
performance hydraulic systems.

7
Good oils are the most economical. Specifications can be set
up which will indicate, to a limited degree, the characteristics
essential in a good hydraulic oil. These are listed herein and
should be checked with the oil manufacturer prior to the use of
this product.
2. Viscosity - Viscosity is the measure of fluidity. The oil
must have sufficient body to provide adequate sealing effect
between working parts of pumps, valving, cylinders, etc., but
not enough to cause pump intake cavitation, sluggish valve
action, or in extreme cases, resistance to flow. Viscosity rec-
ommendations must at best be a compromise, which takes
into consideration the working temperature range, the type of
hydraulic equipment used, and the class of service. Refer to
table of oil viscosity recommendations below.
3. Viscosity Index - The viscosity index is a measure of
the rate at which temperature changes cause a change in oil
viscosity. It is very desirable that the oil viscosity remain as
nearly constant as possible under the wide range of temper-
ature conditions encountered in operating mobile and
construction machinery. The viscosity index (V.I.) of hydraulic
oil should not be less that 90 for this type of service.
4. Additives - Research has developed a number of
additive agents which materially improve various characteris-
tics of oils for hydraulic systems. They may be selected for
compounding with a view toward reducing wear, increasing
chemical stability, inhibiting corrosion, depressing pour point
and improving the anti-foam characteristics. Proper use of
additive agents requires specialized knowledge, and they
should be incorporated by the oil manufacturer only, as
serious trouble may otherwise result.
Most oil companies have several brands of crankcase oils of
somewhat varying formulation that will meet the API service
classification of MS. The more desirable of these oils for
hydraulic service will contain higher amounts of the type of
compounding that avoids scuffing and wear of cam lobes
and valve lifters. These oils will also be formulated to be
stable under oxidative conditions and when in contact with
small amounts of moisture. There should also be reasonable
protection against rust to any ferrous materials submerged in
the oil or covered by the oil’s film.
5. Cleanliness - Thorough precautions should be taken to
filter the oil in the entire hydraulic system prior to its initial use
to remove paint, metal chips, welding shot, lint, etc. If this is
not done, damage to the hydraulic system will probably result.
In addition, continuing filtration is required to remove sludge
and products of wear and corrosion, throughout the life of the
system.
Precautions should be taken in the design of hydraulic
circuits to assure that a means is provided to keep the oil
clean. This can best be accomplished by the use of a 25
micron full-flow filter or a 10 micron by-pass filter (not a
strainer) and a micronic air breather or sealed reservoir.
6. Pump Inlet Conditions - Use of an improper grade of
oil or restrictive inlet piping may result in inlet vacuum condi-
tions exceeding the recommended maximum 5 inches of
mercury, and will reduce the life expectancy of the hydraulic
equipment. Where vacuum exceeds 5 inches of mercury,
and it is not caused by improper oil selection, Vickers is to
be consulted.
7. Operating Temperatures - Operation in excess of
180°F. results in increased wear of the system components
and causes more rapid deterioration of the oil. The hydraulic
system that is designed to maintain a temperature of 160° F.
or less desirable.
8. Grade - Table 3 summarizes the oil types (viscosity
and service classification) that are recommended for use
with Vickers equipment. This selection is most important and
should be made with considerable care.
Hydraulic System
Operating Range
(Min. to Max.) SAE
Viscosity API Service Classification
0°F. to 180°F.
15°F. to 210°F.
32°F. to 230°F.
0°F. to 210°F.
10W
20-20W
30
10W-30
MS
MS
MS
MS
Table 3.
These temperature ranges for each grade of oil are
satisfactory if suitable procedures are followed for low
temperature start-up conditions and if sustained operation is
avoided at the upper temperature limits. For optimum
operation, a maximum oil viscosity of 4000 SSU at low
temperature start-up condition and a minimum oil viscosity of
60 SSU for sustained high temperature operating condition
are recommended. Operation of the fluid at temperatures
below 160°F. is recommended to obtain the maximum unit
and fluid life.
Automatic Transmission Fluid, Type “A”is usually satisfactory
for power steering systems or those systems operating under
moderate hydraulic service.
E. Overload Protection
1. An integral relief valve protects the hydraulic system
components by limiting the maximum pressure.
2. Relief valve sub-assemblies are pre-set and tested by
Vickers for given pressure settings. Selection of the correct
setting should be based on the system work requirements. If
the relief setting must be changed, a replacement valve
should be installed.

8
F. Operating Instructions
Normally these pumps require no manual priming. It is
essential, however, that after starting a minimum drive speed
of 400 rpm be maintained until the pump picks up its prime.
Failure to observe this precaution can result in scoring and
possible seizure of the pump due to a lack of oil for
lubrication.
CAUTION
Do not use hydraulic brake fluid. Use only high
grade hydraulic oil of the viscosities recommended
in paragraph D on Hydraulic Fluid Recommenda-
tions. Do not use fire resistant fluids in Vickers’
products without consulting Vickers’ application
engineering personnel. O-Rings, seals and pack-
ings which are not compatible with petroleum base
fluids are not compatible with synthetic type fluids.
Section V - Service Inspection and Maintenance
A. Service Tools
The only special service tool required is a shaft oil seal
driver. The driver is used to insure that the seal is not
damaged during installation. A piece of tubular round stock
should be machined so that the outside diameter is 1-5/8
inches and inside diameter is 1 inch. The tool must be at
least 2-1/2 inches long and the ends must be squared.
B. Inspection
Periodic inspection of oil condition and pressure connections
will ave time consuming breakdowns and unnecessary parts
replacement.
1. All hydraulic connections must be tight. A loose con-
nection in pressure lines will allow fluid to escape. In suction
and return lines, loose connections will permit air in the
pump, resulting in noisy and erratic operation.
2. System filters and reservoir should be checked for
foreign particles. If contamination is found, the system
should be drained.
a. The reservoir must be cleaned thoroughly before
refilling. All lint particles must be removed to avoid possible
clogging of system filters.
b. New oil of the proper specification, poured through
a micron filter or a 200 mesh screened funnel, should be
used to refill the reservoir.
C. Maintenance
1. All openings in the circuit must be properly capped if a
unit is removed for service. Units removed also should be
capped or plugged to prevent the entry of dirt or other for-
eign matter.
2. These pumps require no adjustments other than main-
taining correct shaft alignment.
D. Lubrication
Lubrication of these pumps is automatically accomplished by
the hydraulic fluid.
E. Trouble Shooting
Table 4 lists the pump difficulties most commonly encountered
and indicates the probable causes and remedies. It must be
remembered that many apparent pump failures can actually
be other units in the system. Improper operation is best
diagnosed with adequate testing equipment and a thorough
understanding of the complete hydraulic system.
F. Spare Parts
Only genuine parts manufactured or sold by Vickers
Incorporated should be used.

9
TROUBLE PROBABLE CAUSE REMEDY
Pump not delivering oil Driven in wrong direction of rotation.
Pump drive shaft disengaged or sheared.
Flow control valve stuck open.
Check direction of pump shaft rotation. It
should rotate clockwise as viewed from the
coupling end of the unit.
See also reassembly instructions for pump
cartridge.
Remove pump. Determine damage to
cartridge parts (see disassembly
instructions). Replace sheared shaft and
needed parts.
Disassemble pump and wash control valve
in a clean solvent. Return valve to its bore
and slide it back and forth. No stickiness in
movement should occur. If a gritty feeling is
noted on the valve O.D. it may be polished
with a crocus cloth. Avoid removal of excess
material or rounding of valve edges during
this operation. Do not attempt to polish the
valve bore. Wash all parts before
reassembly of pump. Fill system with clean
oil per prescribed recommendations.
Pump not delivering oil (Con’t) Vane or vanes stick in rotor slots.
Oil viscosity too heavy to pick up prime.
Disassemble pump. Examine rotor slots for
dirt, grime or small metal chips. Clean rotor
and vanes in a good grade solvent (mineral
oil or kerosene). Reassemble parts and
check for free vane movement.
Use fluid of the proper viscosity as
recommended in oil data (Table 3).
Noisy pump operation Pump intake partially blocked.
Air vent for oil tank clogged or dirty
strainer.
Air being drawn into pump return
connection.
Leaking shaft seal.
Drain system completely. Flush to clear
pump passages. Flush and refill system
with clean oil as per prescribed
recommendations.
Remove filler cap and clean air vent slot.
Check strainer in tank for clogged
condition. Drain, flush and add clean oil to
system.
Pump must receive air-free oil or pump will
be noisy. Drain system. Tighten all hose
connections. Clean or replace filter. Add
clean oil of the proper viscosity.
Check pump shaft seal and replace if
sealing lip has been damaged. Check for
scoring of shaft at seal contact area.
Replace faulty shaft.
Table 4. Troubleshooting Chart

10
Section VI - Overhaul
A. Disassembly
CAUTION
Before removing a unit to be serviced, be sure it is
not under pressure.
1. General - Use a puller to remove shaft gears or pulleys
to prevent damage to the shaft and bearings.
During disassembly, pay special attention to identifi-
cation of parts for proper reassembly. Refer to Figure 5 for
identification of parts in the following discussion.
2. Cover End - Clamp the pump mounting flange in a
vise. Be certain to used protective jaws.
a. VT16 Reservoir - Remove the tank cover screw,
lockwasher, washer, guide and guide gasket. Lift off the tank
cover and gasket and remove the tank screws, tank, gaskets
and spacers.
b. VT17 Manifold - Remove the manifold screws and
manifold and lift off the gaskets and spacers. The remaining
disassembly is the same for both VT16 and VT17 models.
c. Remove the cover screws and separate the cover
from the pump. Remove the control valve sub-assembly and
spring and the cover O-Ring.
NOTE
Control valve sub-assemblies are preset and tested
by Vickers and should not be disassembled. If any
part is defective, the complete sub-assembly should
be replaced.
d. Remove the pressure plate. Note the position of
the pump ring for reassembly. Pull out the ring locating pins
and remove the ring. Remove the vanes from the rotor slots
and slide the rotor off the driveshaft. Remove the body
O-Ring.
3. Shaft End - Remove the driveshaft key. Remove the
bearing retaining snapring and gently tap the splined end of
the shaft to remove the shaft and the outboard bearing. Sup-
port the outboard bearing inner race in an arbor press and
press out the shaft. Remove the seal from the body with a
hooked tool. Remove the inboard bearing from the shaft end
of the body with a bearing puller or by tapping it out from the
cover end.
Figure 5.
Screw
Lockwasher
Washer
Guide
Screw
(Torque to 42-48
inch pounds)
Cover
Gasket
Gasket
Tank
Spacer
Gasket
Screw (Torque to
25-30 foot pounds)
Control Valve
Sub-assemby
Spring
Pressure Plate
Ring Vane O-Ring Body Bearing
Shaft
Snapring
Bearing
Gasket Spacer Key
Seal
Rotor
Pin
O-Ring
Screw
(Torque to 42-48
inch pounds)
Manifold

11
B. Inspection, Repair and
Replacement
Discard all used seals and gaskets. Wash all parts in a clean
mineral oil solvent and place them on a clean, lint-free
surface for inspection. Soak new seals and O-Rings in
hydraulic fluid prior to reasembly.
1. Cartridge, Body and Pressure Plate - Inspect all
wearing surfaces for scoring. Light scoring can be removed
from the body and wear plate with crocus cloth or by stoning
or lapping.
Inspect the vanes for wear. Vanes must not have excessive
play in the rotor slots or burred edges. Replace the vanes if
they are defective. Check each rotor slot for sticky vanes or
for wear. Vanes should drop in the rotor slots from their own
weight when both the rotor vanes are dry.
2. Control Valve Sub-Assembly - Check that the valve
moves freely in its bore in the cover and check the valve and
cover bore for excessive wear and scoring. Replace both the
cover and valve sub-assembly if they are deeply scored.
3. Bearing - Replace the bearings if there is any rough-
ness in their action or if any race or ball is pitted, cracked or
scored.
4. Driveshaft and Shaft Seal - Always replace the seal
at overhaul. Check the sealing journal on the shaft for
scoring. Replace the shaft if it is worn; do not install a worn
shaft with a new seal.
5. Body and Cover - Stone the mating surfaces if there
are any burrs or sharp edges. Rewash the parts after
stoning.
C. Reassembly
1. General - Immerse all parts in clean hydraulic oil to
facilitate assembly and prevent damage to seals.
2. Shaft End - Carefully seat the inboard (body) bearing
in the body by pressing on the outer race. Install the
outboard bearing on the shaft by supporting the inner race
and pressing the shaft into it. Using the shaft seal driver
described in Section V-A, page 7, install the shaft seal with
the lip facing inward. Be sure that both bearings and the seal
are properly seated. Lubricate the seal lip with petroleum
jelly and slide the shaft into position. Install the snapring in
the body.
3. Cover End - Support the body on blocks with the
shaft end down before reassembling the pump cartridge and
cover. Coat the two large O-Rings with petroleum jelly and
install them in the grooves in the body and cover.
a. Place the ring against the pump body so that the
cam contour is the same as at disassembly and the arrows
point in the correct direction of rotation. Install the rotor and
insert the vanes in the rotor so that the radiused edges are
against the ring cam. Position the pressure plate over the
locating pins. Be sure the plate is flat against the ring.
b. Insert the spring in the cover bore and install the
control valve, small land toward the cartridge. Install the
cover over the pressure plate and flush against the ring.
Install the cover screws and tighten them to 25-30 foot
pounds torque. Turn the drive shaft through by hand to be
sure it does not bind.
c. VT17 Manifold - Place the manifold gaskets and
spacers on top of the pump and install the manifold and
screws. Torque tighten the screws to 42-48 inch pounds.
d. VT16 Reservoir - Place the gaskets and spacers
on top of the pump and install the tank and tank screws.
Torque tighten the screws to 42-48 inch pounds. Plug the
ports in the pump cover and fill the reservoir with clean
hydraulic fluid poured through a micron filter. Turn the
driveshaft several times in the proper direction of rotation to
fill all the pump chambers and then refill the reservoir.
Install the tank cover gasket and cover. Assemble the bolt
guide and gasket and install the guide in the cover. Assemble
the lockwasher and washer on the cover screw and install and
tighten the screw.
Section VII - Testing of VT16 and VT17 Pumps
Vickers application engineering personnel should be con-
sulted for recommendations on test stand circuit require-
ments and construction. If test equipment is available pumps
should be tested at speeds and pressures shown on installa-
tion drawings. (See Table 1.)