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A “throw-away” type paper filter element is necessary to maintain its high quality performance. CAV fuel injection pump working principle Filter element life will necessarily vary based on operating conditions, fuel quality and cleanliness, and engine capacity, and operators can advised to operate these filters in accordance with the vehicle or engine manufacturer’s instructions. The real C.A.V. Paper elements should used as alternatives do not provide the same protection and may cause excessive pump wear.

Every precaution shall can taken to prevent the entry of dirt and water into the bulk storage tanks, which shall tend to provide a sump capable of collecting all suspended impurities. A “draw off” pipe should can fitted at the end of the tank away from the sump. CAV fuel injection pump The accumulated sludge should can drained at regular intervals so that it never reaches the level of the “draw off” pipe.

Pump fitting and timing to engine

Both hydraulic and mechanically driven pumps can driven by a spline shaft provided with a master spline. When the master spline can installed it can mated to the corresponding master spline on the engine, ensuring correct positioning for pump timing. CAV fuel injection pump working principle The spline shaft in mechanically driven pumps can referred to as a quill shaft and can detached, but in some applications, the quill shaft can replaced by a special force drive hub, which can bolted to the mechanical coupling.

Pumps have a quill shaft with a small locking screw at one end. It is important that this screw engages the socket head of the drive hub securing screw before the pump can tightened to the engine. Some hydraulically controlled pumps can equipped with a torque bar to iron-out back-lash on the drive shaft. The device consists of a flat bar mounted between the tip of the rotor and the pump drive coupling on the machine. CAV fuel injection pump The bar passes through the center of the drive shaft and turns while connecting the pump to the engine.

CAV fuel injection pump

As the timing and fitting procedure can not standard for all machines, the machine manufacturer’s manual should can consulted before performing this task. CAV fuel injection pump working principle However, in an emergency, and provided the timing marks can clearly marked on the engine and THC pump mounting flanges, most pumps can fitted as follows:-

• Rotate the pump drive shaft so that the master spline can aligned with the master spline on the machine coupling.
• Insert the drive shaft into the engine
• • Insert the coupling while the pump can pushed onto the securing stud.
• Press the pump firmly onto the mounting face and lightly secure with the three retaining nuts.
• Rotate the pump onto the retaining stud until the timing mark on the side of the pump mounting flange can properly aligned with the timing mark on the engine.
• Tighten the retaining nuts. CAV fuel injection pump
• Connect and tighten the back-leak GC pipe.
• Connect the fuel hose to the inlet fitting on the pump end plate and tighten.
• Connect the “shut off” lever on the pump to the control linkage and ensure that the lever has a full range of motion when the control can turned on.

Connect the throttle lever on the pump to the throttle control linkage and make sure the lever has a full range of motion when operating the control. When you are driving, set the control stop so that the pressure of the accelerator pedal does not reach the maximum speed stop of the pump. Installation instructions should can included in the manufacturer’s manual.

Failed to start

Starting problems can not always caused by faulty fuel injection May be a result of poor compression by equipment and cylinder Worn, CAV fuel injection pump working principle gummed rings, stuck or poorly seated valves, or Inadequate pipe clearance. Difficulty occurs when no initial support can used

Can enjoyed when starting in very cold weather.

1. Make sure there is fuel in the tank and the fuel cock can turned on. If the tank can drained, after refilling the tank, CAV fuel injection pump working principle the pump should can primed and primed according to the instructions
2. Test the position of the “close Off” control. Inspect the injector pipe fitting for oil leakage and tighten as necessary.
3. Fill and prime the pump to remove all air from the system. CAV fuel injection pump
4. Inspect the filter element and replace it if it can clogged. Initialize the system after reconnecting the filter.
5. After removing each injector and reconnecting the high pressure injector hose to the end removed from the engine, start the engine and ensure proper spraying and atomization of the fuel sent through the injectors can achieved Replace any faulty injectors.

Defect correction

Listed below are possible causes of difficult running, including proper treatments.

Faulty injector

Remove each injector, reconnect the high-pressure hose to the injector nozzle away from the engine, and crank the engine to ensure that the fuel passing through the injectors can properly sprayed and atomized. CAV fuel injection pump Replace faulty injectors.

Leakage injection pipe unions

Inspect all unions for symptoms of oil leakage and tighten as important.

Clogged filter

Remove and replace the paper filter element, and prime as directed

Air in the pump

Loosen each injector pipe connection while the engine is running (at the injector end), and retighten when oil, free of air bubbles, CAV fuel injection pump working principle leaks from the union threads. If engine performance does not improve, prime pump as directed.

Water in fuel

When water in the fuel can suspected, drain the filter bowl daily and the amount of water removed indicates that draining should can done less frequently to prevent water from entering the fuel injection pump. CAV fuel injection pump If more than one cup of water leaks out, either find the source of entry or drain the filter bowl at frequent intervals. If rough running persists even after performing the above checks, consult the nearest CAV. Get advice. Find an agent.

Fuel gauge

Fuel entering the pump through an inlet connection on the pump end plate passes through a fine mist filter on the inlet side of the vane type transfer pump. The fuel pressure can then increased to an intermediate level called transfer pressure, and can controlled by a piston-type regulating valve located on the end plate. CAV fuel injection pump The transfer pressure is not constant, but increases with the speed of rotation of the pump.

• The fuel under transfer pressure then passes through a passage in the hydraulic head to an annular groove in the rotor and from there to a chamber with a metering valve.
• The metering valve can operated by the control lever and regulates the flow of fuel CAV fuel injection pump through the metering port in the pumping section of the rotor.
• The amount of fuel entering the pumping element can controlled by the transfer pressure.
• the position of the metering valve and the time it takes for the inlet section in the rotor to align with the metering port in the hydraulic head.

Pumping and distribution

The functions of pumping and dispensing metered fuel can depicted. CAV fuel injection pump working principle

• The left-hand graph shows the charging status and the right-hand graph shows the actual pumping and distribution of metered charge. As the rotor rotates, the charging port
• The rotor aligns with a meter port in the hydraulic head and fuel at meter pressure flows
• Into the center passage in the rotor and pushes the plungers. CAV fuel injection pump The amount of piston displacement can determined by the amount of fuel flowing into the element
• when the ports can aligned. See the left-hand diagram.
• As the cycle continues, the inlet port closes, and as the single distributor port in the rotor aligns with one of the distributor ports in the hydraulic head,
• The actuating rollers contact the cam ring lobe, and the plunger can forced inward as shown. CAV fuel injection pump Right hand diagram. High pressure can created and fuel can forced into the injector.

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• Apart from the occasional replacement of the filter element and service of the injector nozzles,
• The fuel system comprising the DPA type fuel injection pump requires no maintenance.
• The pump will provide many thousands of hours of trouble-free service
• If proper attention can paid to fuel cleanliness in both the fuel system and the total storage installation.

Conclusion

If the vehicle is to be idle for a long period of time, for example, during storage or when traveling abroad, the pump and fuel injection system must can protected against corrosion in the following manner. CAV fuel injection pump Each specific installation must can tailored to the fuel layout requirement. In general, the principle to observe is that as much of the existing fuel as possible should

it can drained from the tank, filters and pipe work and injectors. CAV fuel injection pump The entire system should then can filled with stainless fuel, the pump primed and primed, the engine run for a sufficient period of time to ensure that the entire system has broken down. Detailed instructions for any vehicle, tractor or installation should be provided in the manufacturer’s manual and followed closely. Further information and literature on interception and storage of fuel oils are available from all C.A.V. Available from Agents and Depots.