Delivery Valves

Delivery Valves

A diesel delivery valve is one component of the diesel fuel injection system. The valve controls fuel delivery into the combustion chamber and fuel flow from the injection pump to the fuel injectors. When a vehicle's engine is running, the fuel pump pushes pressurized fuel through the delivery valve and into the fuel injectors.

When fuel injection pump pistons reach the end of their stroke, the delivery valve opens, and pressurized fuel moves into the injector. When the piston returns to the starting position, it closes the delivery valve and prevents fuel from returning to the pump. A properly functioning delivery valve is vital for peak engine performance, power output, and efficient fuel economy.

Goldfarb & Associates has new and rebuilt delivery valves for sale. New engine parts are always in demand, and with so many used and refurbished parts in stock, you may want to consider the benefits of cost-effective rebuilt delivery valves.

Components of a Delivery Valve

Diesel delivery valves are found within a fuel pump and are made up of several moving parts that work together to control the timing and amount of fuel delivery. All of these separate parts must function optimally to ensure the engine performs well. Regular maintenance of the fuel injection system is recommended. Here are the different parts of a diesel delivery valve:

1. Body

The main body of the delivery valve holds the spring assembly and valve seat.

2. Valve Seat

The valve seat is inside the body of the delivery valve and prevents fuel leakage by forming a seal with the valve plunger.

3. Valve Plunger

A valve plunger is a cylindrical part of the delivery valve that moves up and down to control fuel flow. The plunger attaches to the camshaft of the fuel injection pump and operates with the engine’s rotation.

4. Fuel Inlet

This point allows fuel to enter the delivery valve body from the injection pump.

5. Fuel Outlet

This point allows fuel to exit the delivery valve and enter the fuel injection pump.

6. Spring

The spring is found inside the valve body and keeps the valve plunger in the closed position by applying pressure.

Types of Diesel Delivery Valves

Different delivery valve types used in fuel injection systems will function best depending on the engine design. Delivery valve types may be chosen based on engine applications to optimize emission, engine performance, and fuel delivery. Here are some common types of delivery valves:

1. Pintle Delivery Valve

This delivery valve type contains a small, pointed valve stem called a pintle. The pintle is held in place by a spring. The pintle lifts off the seat to allow fuel flow through the valves and into injectors.

2. Disc Delivery Valve

A disc delivery valve utilizes a flat disc that is held by a spring against a seat. When the fuel pump rocker arm or camshaft lifts the valve disc, it lifts off the seat, allowing fuel to enter the valve.

3. Ball Delivery Valve

A ball delivery valve holds a ball-shaped valve against the seat by a spring.

4. Cone Delivery Valve

A cone delivery valve uses a conical-shaped valve..

5. Needle Delivery Valve

A needle-type delivery valve uses a needle-shaped valve element.

Delivery Valve Cycles

A diesel intake fuel valve opens to allow fuel and air to flow into an engine’s cylinders. Valves and cylinders work together to perform these four cycles:

1. The Intake Cycle

The intake cycle is the first of the valve cycles. The cylinder piston cycles downward and draws the fuel and air into a cylinder with negative pressure. The intake valve will stay open until the piston reaches the lowest point of the cylinder.

2. The Compression Cycle

The second valve cycle is the compression cycle. When the intake valve closes and seals off the cylinder, the movement will compress the fuel and air. This compression increases the temperature of the fuel, helping it burn more efficiently. It also helps to create more pressure when the fuel ignites. During this cycle, more fuel is injected by the injection pump.

3. The Power Cycle

The power cycle is the third valve cycle. Fuel injected into the compressed fuel and air mixture trapped in the cylinder will cause the fuel and air to ignite and explode. The explosion pushes the piston back down to the bottom, and the explosion transfers energy.

4. The Exhaust Cycle

The exhaust cycle is the last cycle. The piston rises with the exhaust valve open. With the intake valve closed, exhaust gasses exit the exhaust valve and enter the exhaust manifold.

Common Delivery Valve and Injector Pump Issues

1. Leaking Valve

When a fuel pump plunger wears out, there can be fuel leakage in the injector pump. This issue prevents the pump from reaching sufficient pressure to open the valve and delays injection. It also means the amount of fuel delivered will need to be improved.

2. Dirty Fuel

Dirty fuel entering a pump injector and fuel system can cause residue to build up and clog the system. The fuel injector’s spray pump is especially prone to clogging. If you’ve heard your engine sputter or hesitate during acceleration, a clogged tip from dirty fuel might be the cause.

3. Something Stuck Inside the Injector

Getting a foreign body stuck inside the fuel injector, even something small like a piece of dust or debris, could clog the entire fuel injection system. A foreign object could also keep the valve open, compromising engine performance.

4. Low Fuel Tank

Driving with a fuel tank that is close to empty can cause significant damage to fuel injectors. Diesel fuel provides lubrication to the pump bearings. A nearly empty tank presses air instead of fuel onto the bearings, wearing them out.

5. Bad Timing

With damaged O-rings or ball bearings, the timing of a fuel injection system can be disrupted. Once a fuel injector reaches this stage, you will most likely need a total replacement.

Delivery Valve FAQs

Q: Are rebuilt delivery valves a good investment?

A: This depends on where you buy used and rebuilt diesel engine parts. Goldfarb & Associates works with a trusted network of reputable suppliers and manufacturers who guarantee their work. Each rebuilt delivery valve will be carefully inspected before being sold and fitted to your vehicle. Our used diesel engine parts will last for many years with regular maintenance.

Q: What are the signs that a delivery valve is giving out?

A: Faulty delivery valves can result in various issues, including rough idling, hard starts, too much exhaust smoke, decreased fuel efficiency, and reduced engine performance.

Q: How can you diagnose a faulty delivery valve?

A: A trusted mechanic can diagnose a faulty delivery valve with a fuel pressure test or physically inspect the valve for signs of damage or wear.

Q: How often should delivery valves be serviced?

A: Delivery valves should be serviced with routine maintenance inspection. The frequency of inspection recommended will depend on the manufacturer, age, and engine condition.

Q: How do I know if a rebuilt delivery valve is high quality?

A:When looking at rebuilt delivery valves, you will want to inspect the quality of the rebuild and whether it meets high standards. Invest with a reputable supplier who uses high-quality parts. You will want to ensure the rebuilt valve is compatible with your vehicle's engine. A warranty when buying used and rebuilt engine parts is always a good idea. And last, compare the price with new delivery valve parts to ensure that a rebuilt option makes the most sense for your vehicle and your budget.

Delivery Valves for Sale

Goldfarb & Associates has been supplying customers with the highest-quality diesel engine parts for over 20 years. We stand by our inventory of used, new, and remanufactured components. Goldfarb has the experience necessary to identify the suitable valve for your vehicle. Whether you're looking for a passenger car, commercial vehicle, or anything in between, we have the OEM quality delivery valves you need.

Goldfarb & Associates can locate even the rarest of engine parts. If it can be found, we can find it! By careful inspection and testing, we ensure that each diesel delivery valve meets or exceeds the highest standards. Goldfarb understands the complexity of engine components and can diagnose and replace or repair the parts to get your engine running.

Our engine parts are carefully packaged from our Rockville, Maryland, headquarters. We offer free shipping anywhere in the United States. Explore our inventory online, or come see our warehouse in person to find delivery valves for your diesel engine.