Additional Information

Sealey VS403 Vacuum & Pressure Test / Bleed Kit

Before attempting to operate the Sealey VS403 Vacuum & Pressure Test / Bleed Kit , carefully read through the entire instruction manual, to understand the applications limitations and potential hazards associated with this vacuum & pressure tester. Failure to do so could lead to serious personal injury. Take note of the important safety instructions. Your vacuum & pressure tester has many features that will make your job faster and easier. Performance and dependability have been given top priority in the development of this tool.

This professional vacuum/pressure diagnostic tool helps identify a variety of faults on vehicle systems including fuel, ignition, transmission, emission and air conditioning/heating. The set also includes reservoirs, hoses and adaptors for bleeding brake and clutch systems. Features lightweight aluminium body with simple twist function for choice of pressure or vacuum testing. Large rubber easy-to-read gauge. Contents: Vacuum Pump, 2 x Fluid Container, Transfer Cap, Vacuum Hoses; 2 x 80mm, 2 x 95mm, 2 x 600mm, 19 x Assorted Connectors and blanking caps.

Application
The use of a vacuum/pressure 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.

Below are some applications that the VS403 vacuum/pressure 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, ie. compression tests, cylinder leakage tests, ignition timing checks etc. be carried out to confirm indications of vacuum/pressure gauge readings.

This hand pump and its adaptors can be used to test vacuum motors and control valves as well vacuum or pressure operated systems and components that require to be properly sealed. The pump and its associated accessories can also be used to bleed brakes. In pressure testing mode the pump may be utilised to dispense or transfer liquids and provide slight pressure during gravity or pressure bleeding. The VS403 can be used for both pressure and vacuum testing by means of the ribbed mode selector on the front of the pump.

Ignition System Vacuum Advance
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. 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.

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’s specifications. In the event that the vacuum advance is not operating, remove the vacuum line from the distributor advance mechanism. Connect the VS403 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 VS403 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 or breaks.

FUEL SYSTEMS

Testing Mechanical Fuel Pumps
The VS403 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 VS403 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 15 inHg 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.

Carburettors
There are many different types of vacuum control systems used on carburettors. Using the VS403 vacuum tester kit allows quick and accurate testing of these systems.

Testing Fuel Injection Pressure Regulator
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. To test the fuel rail pressure, a gauge is attached to the rail, then engine loads must be created to vary engine manifold vacuum. Simply remove and block off the vacuum supply line to the pressure regulator, connect and operate the VS403
vacuum pump to simulate vacuum pressures in accordance with the manufacturer’s specifications and note variation in fuel pressure reading.

Testing Vacuum Operated Remote Central Locking Systems
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. In either system, the VS403 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 VS403 vacuum tester 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 VS403 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.

BRAKING SYSTEMS

Testing Brake Servo Diaphragm
Remove vacuum supply line from brake servo fitting. Attach VS403 vacuum tester to vacuum supply port on servo. 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.

Brake Bleeding
Ensure that the vacuum pump is connected to the brake bleeder reservoir in accordance with the assembly instructions. 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.

For further applications and instructions see the pdf documents below.

Sealey VS403 Vacuum & Pressure Test Bleed Kit - Instructions

Sealey VS403 Vacuum & Pressure Test Bleed Kit - Parts