Sealey VS4021.V2 User manual

Thank you for purchasing a Sealey product. Manufactured to a high standard, this product will, if used according to these instructions,
and properly maintained, give you years of trouble free performance.
IMPORTANT: PLEASE READ THESE INSTRUCTIONS CAREFULLY. NOTE THE SAFE OPERATIONAL REQUIREMENTS, WARNINGS & CAUTIONS. USE
THE PRODUCT CORRECTLY AND WITH CARE FOR THE PURPOSE FOR WHICH IT IS INTENDED. FAILURE TO DO SO MAY CAUSE DAMAGE AND/OR
PERSONAL INJURY AND WILL INVALIDATE THE WARRANTY. KEEP THESE INSTRUCTIONS SAFE FOR FUTURE USE.
1. SAFETY
9Keep this product in good working order and condition, take immediate action to repair or replace damaged parts.
9Use approved parts only. Unapproved parts will invalidate the warranty.
9Keep children and unauthorised persons away from the work area.
9Keep work area clean and tidy and free from unrelated materials.
9Ensure the work area has adequate lighting.
8DO NOT use the kit to perform a task for which it is not designed.
8DO NOT hold pump inlet against the skin whilst using the pump.
8DO NOT allow untrained persons to use the kit.
8DO NOT use whilst under the inuence of drugs, alcohol or intoxicating medication.
9After use, clean equipment and store in a cool, dry, childproof area.
WARNING! Brake uid will damage paintwork. Any spillage should be ushed with water immediately.
WARNING! Brake uid is ammable - keep away from sources of ignition, including hot surfaces e.g. exhaust manifold.
9Dispose of waste liquids in accordance with local authority regulations.
WARNING! DO NOT pollute the environment by allowing uncontrolled discharge of uids.
9 Always read and comply with the warnings on the brake fluid container.
9 Wear eye protection and keep skin contact to a minimum. If brake fluid enters eyes rinse with plenty of water and seek medical advice.
IMPORTANT: If swallowed seek medical advice immediately.
2. INTRODUCTION
Multi-function diagnostic tool used to test a variety of essential engine and associated functions including fuel, ignition, transmission and
emissions. Kit also includes reservoir, hoses and adaptors for bleeding brake and clutch systems on cars, commercials and motorcycles. Brass-
bodied vacuum pump features large, easy-to-read vacuum gauge calibrated in both inches and millimetres of mercury.
3. CONTENTS
VS4021.V2 | Issue 2 (F,2,3) 26/02/19
Original Language Version
© Jack Sealey Limited
Refer to
instructions Wear protective
gloves
Wear eye
protection
ITEM PART No. DESCRIPTION
1VS402.V3-01 VACUUM PUMP WITH GAUGE
2A VS402.V3-02A RESERVOIR LID (FOR OPERATION)
2B VS402.V3-02B RESERVOIR LID (FOR TRANSPORT)
3VS402.V3-03 RESERVOIR JAR
4VS402.V3-04 560mm VACUUM HOSE
5VS402.V3-05 80mm VACUUM HOSE
6VS402.V3-06 HOSE ADAPTOR
7VS402.V3-07 HOSE ADAPTOR ‘T-PIECE’
8VS402.V3-08 HOSE ADAPTOR ‘STRAIGHT’
9VS402.V3-09 BRAKE BLEED NIPPLE ADAPTOR
10 VS402.V3-10 UNIVERSAL CUP ADAPTOR
VACUUM TESTER & BRAKE BLEEDING KIT
MODEL NO: VS4021.V2

4. OPERATION
The use of a vacuum gauge is often overlooked when determining mechanical condition and carrying out fault diagnosis on internal combustion
engines. Monitoring actual manifold vacuum is invaluable when troubleshooting engine faults. This can only be carried out by using a good
quality vacuum gauge and this, coupled with a hand-operated vacuum pump, also allows static testing of all types of vacuum operated systems.
Set out on the following pages are applications that the VS4021 vacuum tester kit can be used for, but it must always be remembered that these
are examples only and reference to manufacturer’s service manuals should always be made for correct testing procedures and specifications.
In addition to this, it is always recommended that additional tests, i.e. compression tests, cylinder leakage tests, ignition timing checks etc. be
carried out to confirm indications of vacuum gauge readings.
5. INLET MANIFOLD SYSTEMS
5.1. ANALYSING ENGINE MECHANICAL CONDITION VIA MANIFOLD VACUUM READINGS
5.1.1. The readings shown below are only examples of what may be observed.
IMPORTANT: Remember that it is the action of the needle rather than
the actual reading that is more important. Varying engine types will run
different manifold vacuum pressures, depending on camshaft profile,
valve overlap, timing etc. so an exact vacuum reading cannot be
specified.
The main criteria is that the needle reading is between 16 to 21 inHg
and steady.
5.1.2. Manifold vacuum is also affected by altitude and it will drop
approximately 1inHg for every 1000 feet above sea level so this must
also be considered when assessing manifold vacuum actual readings.
5.2. BASIC DIAGNOSTIC TESTS
5.2.1. Carry out the following procedures:
Step 1. Run engine until normal operating temperature is reached.
Switch engine off.
Step 2. Connect the vacuum gauge to a port directly on the manifold (fig.1) or on the carburettor/throttle body below the throttle
butterfly.
Step 3. Start and run the engine at idle, observing the gauge reading. Refer to the following table to indicate any problems and their
possible causes.
READING: Reading low but steady.
CAUSE: Retarded ignition timing.
Conrm using timing light and reset
to manufacturer’s specication.
VS4021.V2 | Issue 2 (F,2,3) 26/02/19
Original Language Version
© Jack Sealey Limited
g.1
READING: When the throttle is
suddenly opened then released the
needle should drop to below 5inHg
then bounce up to approx. 25 inHg
settling back to original reading.
CAUSE: Normal.
READING: 16-21 inHg with needle
steady.
CAUSE: Normal.
READING: Reading extremely low but
steady.
CAUSE: Leaking manifold intake
system, faulty manifold gasket,
carburettor base gasket, split vacuum
hose, EGR valve seized.
READING: Reading slightly low and
uctuating slowly.
CAUSE: Over lean or rich mixture.
Check and reset in accordance with
manufacturer’s specications.
READING: Regular uctuation
between normal and low readings.
CAUSE: Blown cylinder head gasket
between two adjacent cylinders. Carry
out cylinder leakage test.

5.3. IGNITION SYSTEM VACUUM ADVANCE
5.3.1. On standard points systems and some electronic ignition systems there are two types of advance methods used, both of which must
function correctly to obtain maximum performance and fuel economy.
5.3.2. The first method Is Mechanical or Centrifugal, which operates by the use of weights located in the base of the distributor. The weights
move outwards advancing ignition timing as engine RPM increases. This is tested by firstly removing the vacuum advance line to
disable the system, then with a timing light connected, run the engine RPM up checking that the timing advances in accordance with
the manufacturer’s specification.
5.3.3. The second method is Vacuum Advance, which senses engine load via manifold vacuum. A vacuum diaphragm is mounted onto the
distributor and connected to a rotating internal base plate which advances or retards timing as required to suit varying engine loads.
To test this system for correct operation, again with the timing light connected, raise the engine RPM and check timing advance
against manufacturer specifications. In the event that the vacuum advance is not operating, remove the vacuum line from the
distributor advance mechanism. Connect the VS4021 (fig.2) and create a 5-10 inHg vacuum, monitoring the timing at the same time.
If a timing advance is noted this confirms that the vacuum diaphragm and mechanical links are in order and that the fault is a vacuum
supply. To confirm this, connect the VS4021 to the vacuum supply line and check the gauge reading. No vacuum should be noted
at idle but when the engine RPM is increased a vacuum increase should be observed. If this does not occur, trace the vacuum line
back checking for restrictions and breaks.
6. FUEL SYSTEMS
6.1. TESTING MECHANICAL FUEL PUMPS
6.1.1. The VS4021 vacuum tester can be used to evaluate the condition of a mechanical fuel pump by testing the vacuum that it is able to
create. Locate and remove the suction line from the pump. Connect the VS4021 vacuum tester to the suction port of the
pump, start and run the engine at idle. The vacuum reading that should be observed will vary slightly on different makes and models
but as a general rule approximately 15inHg of vacuum should be created. This should also be held for approximately 1 minute
after engine shut down. If this vacuum reading is not achieved or the vacuum drops off immediately with the engine shut down, the fuel
pump requires either overhaul or replacement.
6.2. CARBURETTORS
6.2.1. There are many different types of vacuum control systems used on carburettors. Using the VS4021 vacuum tester kit allows quick and
accurate testing of these systems. Listed below are just two examples of tests that can be carried out:
6.2.2. Testing a Choke Break Diaphragm. With the engine at normal operating temperature but not running, disconnect the vacuum line to
the diaphragm module. Connect the VS4021 vacuum tester (fig.3) and apply approximately 15inHg of vacuum and wait for 30 seconds.
No drop in gauge reading should be observed. With the vacuum still applied ensure that the choke butterfly is pulled to the fully open
position.
6.2.3. Testing Vacuum Operated Carburettor Secondary Barrel. With the engine at normal operating temperature but not running, remove
the vacuum line from the secondary diaphragm module. Connect the VS4021 vacuum tester (fig.4), hold the throttle and secondary air
valve flaps open. Operate the hand pump whilst observing free and easy opening of the secondary throttle butterfly.
6.3. TESTING FUEL INJECTION PRESSURE REGULATOR
6.3.1. Multi-point fuel injection rail pressure must vary to suit changing engine loads and fuel delivery requirements. This is done using a
vacuum operated regulator which is connected to the engine manifold vacuum to sense the varying loads.
6.3.2. To test the fuel rail pressure, a gauge is attached to the rail, then engine loads must be created to vary engine manifold vacuum.
READING: Readings slightly lower
than for lower for normal engine
including when throttle is suddenly
opened then released.
CAUSE: Worn piston rings. Carry out
compression test.
READING: Regular drop between
normal and low reading.
CAUSE: Burnt valve.
READING: Normal when rst started
but drops rapidly when revs held at
3000rpm.
CAUSE: Restriction in exhaust system.
VS4021.V2 | Issue 2 (F,2,3) 26/02/19
Original Language Version
© Jack Sealey Limited
g.2 g.3 g.4

6.3.3. Simply remove and block off the vacuum supply line to the pressure regulator, connect and operate the VS4021 vacuum pump (fig.5)
to simulate vacuum pressures in accordance with the manufacturer’s specifications and note variation in fuel pressure reading.
6.4. TESTING EMISSION CONTROL EXHAUST GAS RECLRCULATION VALVES (EGR)
6.4.1. Start engine and run at idle until normal operating temperature is reached. Remove the vacuum line from the EGR valve and attach
the VS4021 vacuum tester kit (fig.6). Operate the hand pump to apply approximately 15 inHg of vacuum. If the EGR Valve is working
correctly the engine idle will become rough. If the idle remains unchanged the valve is possibly seized in the closed position. If the
vacuum is not held, the diaphragm in the valve has failed.
7. ADDITIONAL VACUUM SYSTEMS
7.1. TESTING ONE-WAY VALVES
7.1.1. Many vacuum operated circuits use in-line one-way valves to apply vacuum in one direction only.
7.1.2. To test the function of the valve remove it from the circuit. Attach the VS4021 vacuum tester (fig.7) and operate pump to apply vacuum.
In one direction the valve should hold vacuum and in the opposite direction it should not.
7.2. TESTING ELECTRICALLY OPERATED VACUUM SOLENOIDS
7.2.1. Electrically operated vacuum solenoids are commonly used in control circuits for air conditioning/ventilation systems, emission control
systems, idle step up systems etc. and testing the function of these when using the VS4021 is extremely simple.
7.2.2. Locate the solenoid to be tested and remove the line that goes to the component being tested. Connect the VS4021 to the solenoid
port (fig.8) and start the engine. With the system turned off there should be a zero gauge reading. Now turn the system to the ‘on’
position and a gauge reading equal to the manifold vacuum should be observed, if no reading exists remove the vacuum supply line
and test for manifold vacuum at this point. If the vacuum does exist this indicates that the solenoid is faulty or it is not receiving a
‘switch on’ voltage (use a multimeter to test this). If no vacuum exists trace the supply line back to the vacuum source checking for
kinks and breaks.
7.3. TESTING THERMAL VACUUM SWITCHES
7.3.1. There are many vacuum controlled circuits that must only operate when the engine reaches normal operating temperature. This is
done using thermal switches that remain in an ‘off’ position until a given temperature is reached.
7.3.2. To test this type of switch, remove the vacuum supply line coming from the manifold to the switch and test for manifold vacuum. If this
vacuum is correct refit the supply line to the thermal switch and remove the opposing line from the switch. Attach the VS4021 vacuum
tester to the port (fig.9) and start the engine. With a cold engine no reading should be noted. When the engine reaches normal
operating temperature a manifold vacuum reading should be noted.
VS4021.V2 | Issue 2 (F,2,3) 26/02/19
Original Language Version
© Jack Sealey Limited
g.5 g.6
g.7 g.8
g.9

7.4. TESTING VACUUM OPERATED HEATER TAPS
7.4.1. Climate control ventilation systems are becoming very common on newer vehicles and most of the systems use vacuum operated taps
to control the heating modes. On the majority of makes and models, the system uses vacuum to turn the heater tap ‘on’.
7.4.2. To test these remove the supply line from the tap vacuum module and connect the VS4021 vacuum tester (fig.10). With the engine at
normal operating temperature locate and feel the heater return hose. With the heater tap in the ‘off’ position, this hose should be cold.
Now operate the vacuum pump to open the tap. The gauge reading must hold. If the tap is in working order, the return hose will begin
to heat. If the hose does not begin to heat, this indicates that the tap is faulty.
7.5. TESTING VACUUM OPERATED REMOTE CENTRAL LOCKING SYSTEMS
7.5.1. Some makes and models use vacuum operated bellows mounted in each door to centrally lock and unlock the vehicles doors. These
systems use either manifold vacuum stored in a reservoir for use when the engine is not running or an electrically driven vacuum
pump which operates when the doors are locked or unlocked.
7.5.2. In either system, the VS4021 vacuum tester is ideal for testing each individual door bellows. To do this, remove the door trims as
required. Remove the vacuum supply lines from the bellows and attach the VS4021 vacuum tester (fig.11) and operate to apply vacuum
to the bellows. Wait for 30 seconds, no drop on the gauge should be noted. If the bellows are found to be in order attach the vacuum
supply line to the VS4021 vacuum tester and operate system to test for vacuum supply. If the vacuum supply does not exist or is low
trace back down the lines to the vacuum supply looking for kinks, restrictions or cracked lines. Repair as required and retest.
7.6. TESTING AUTOMATIC TRANSMISSION VACUUM OPERATED MODULATOR VALVES
7.6.1. Automatic transmissions are normally equipped with a vacuum operated modulator valve in order for the automatic transmission to
detect engine loads and adjust shift points to suit.
7.6.2. The VS4021 vacuum tester can be used to test both that the modulation valve diaphragm is serviceable and also to simulate varying
engine loads so modulator pressure readings can be recorded. To test the modulator valve diaphragm remove the vacuum supply line
from the valve and attach the VS4021 vacuum tester. Operate the vacuum pump until approximately 15 inHg is achieved and monitor
the gauge reading for approximately 30 seconds. No vacuum drop should be noted.
7.6.3. To check modulator pressure readings attach a pressure gauge to the appropriate port on the transmission. Remove the vacuum
supply line from the modulator and attach the VS4021 vacuum tester (fig.12). Start and run the engine and apply vacuum pressures.
Monitor readings and confirm that these are in conformance with manufacturer specifications.
8. BRAKING SYSTEMS
8.1. TESTING BRAKE SERVO DIAPHRAGM
8.1.1. Remove vacuum supply line from brake servo fitting. Attach
VS4021 vacuum tester to vacuum supply port on servo (fig.13).
Operate pump to create approximately 15 inHg of vacuum and
wait for 30 seconds. No vacuum drop should be observed on the
gauge reading. If the vacuum drops this indicates that the brake
servo diaphragm is faulty. In this case the servo should be
removed for overhaul by an authorised repairer or replaced.
8.2. BRAKE BLEEDING - ASSEMBLY OF BRAKE BLEEDER KIT
8.2.1. Ensure that the vacuum pump is connected to the brake bleeder
reservoir in accordance with the assembly diagram (fig.14). Failure
to do so will result in brake fluid being drawn into the vacuum pump.
VS4021.V2 | Issue 2 (F,2,3) 26/02/19
Original Language Version
© Jack Sealey Limited
g.10
g.11
g.12 g.13
g.14

8.3. BRAKE BLEEDING PROCEDURE
WARNING! Familiarise yourself with the hazards of brake uid - read manufacturer’s instructions on the container.
8.3.1. IMPORTANT: DO NOT touch the vehicle’s brake pedal whilst bleeding the brakes.
8.3.2. Refer to the specific vehicle manufacturer’s instructions for brake bleeding and wheel sequence procedure before proceeding. If no
specific instructions from the vehicle manufacturer exist, follow the instructions detailed below.
8.3.3. Remove the cap of the vehicle’s master brake fluid reservoir. If the fluid level is not at maximum, top it up.
8.3.4. Attach the appropriate size bleeding attachment to the bleed nipple on the brake calliper of the first wheel, normally nearest to master
brake fluid reservoir (fig.15).
8.3.5. Operate vacuum pump until approximately 21inHg vacuum is created.
8.3.6. Apply copper grease to the brake bleeding nipples before and after the brake bleeding procedure to reduce the possibility of seized or
broken nipples when the brakes are next bled.
8.3.7. Open the bleed nipple about a quarter of a turn. Allow brake fluid to be drawn until no air bubbles are visible in the brake fluid in the
clear hose.
8.3.8. Tighten the bleed nipple.
8.3.9. Remove the attachment from the brake nipple.
8.3.10. Repeat the process as necessary.
NOTE! Check the master brake fluid reservoir regularly to ensure that
the level does not drop too far, and top up as necessary.
NOTE! Empty bleeder container regularly and DO NOT allow
container to overfill as brake fluid will be drawn into vacuum pump.
WARNING! When brake bleeding and/or fluid changing is
complete, test the action of the brake pedal to ensure that the
brakes are working before attempting to drive the vehicle on the
road and test the vehicle for satisfactory performance of the
braking system.
8.4. CLUTCH BLEEDING PROCEDURE
8.4.1. Refer to the relevant vehicle manufacturer’s instructions for clutch
bleeding procedure. If no specific instructions from the vehicle
manufacturer exist, follow the same basic procedure as the brake
bleeding instructions above.
VS4021.V2 | Issue 2 (F,2,3) 26/02/19
Original Language Version
© Jack Sealey Limited
Sealey Group, Kempson Way, Suffolk Business Park, Bury St Edmunds, Suffolk. IP32 7AR
01284 757500 01284 703534 [e-mail] www.sealey.co.uk
ENVIRONMENT PROTECTION
Recycle unwanted materials instead of disposing of them as waste. All tools, accessories and packaging should be sorted, taken to
a recycling centre and disposed of in a manner which is compatible with the environment. When the product becomes completely
unserviceable and requires disposal, drain any fluids (if applicable) into approved containers and dispose of the product and fluids
according to local regulations.
Note: It is our policy to continually improve products and as such we reserve the right to alter data, specifications and component parts without prior notice.
Important: No Liability is accepted for incorrect use of this product.
Warranty: Guarantee is 12 months from purchase date, proof of which is required for any claim.
Parts support is available for this product. Please log on to www.sealey.co.uk, email [e-mail] or telephone [phone]
g.15