Best Places To Buy 855 Cummins Fuel Pressure Spring

The 855 Cummins is a diesel engine used in heavy equipment and trucks. To increase its power output, some operators modify the engine's fuel system by changing the fuel button, which regulates fuel pressure. This procedure can be dangerous and should only be performed by experienced professionals. While Cummins distributors are a good source for fuel buttons, operators should exercise caution when making these modifications, as incorrect adjustments can cause engine damage.

Where to buy a Cummins 855 fuel pressure spring online

The 855 Cummins engine is a powerful piece of machinery, but even the toughest engines can use a boost now and then. If you're looking to increase fuel pressure and want to know where to buy a Cummins 855 fuel pressure spring online, here are some options to explore:

Online Marketplaces:

• EBay Motors: eBay is a well-known online marketplace that offers a wide range of products, including automotive parts. A quick search on eBay Motors may yield results for Cummins 855 fuel pressure springs, as well as other related parts and accessories.
• Specialized Websites: Websites such as Steelsoldiers.com and HeavyEquipmentForums.com are dedicated to enthusiasts of heavy equipment and vehicles. These sites often have forums where members can discuss various topics, including engine modifications. It's worth exploring these forums or creating an account to connect with other Cummins 855 owners and seek their advice on where to find the specific spring you need.

Official Cummins Dealers:

• Cummins Online Store: Cummins, the manufacturer, has an online store where you can purchase parts and accessories. They may have the fuel pressure spring you need, and their website can provide valuable information about part numbers and specifications.
• Authorized Cummins Dealers: In addition to the online store, Cummins has authorized dealers and distributors worldwide. These dealers may have physical locations or online stores where you can purchase the spring. Visit the Cummins website to locate a dealer near you or one that offers online purchasing options.

Other Online Retailers:

• Automotive Parts Stores: Many retailers specialize in automotive parts and accessories, such as AutoZone, O'Reilly Auto Parts, or NAPA Auto Parts. They may carry Cummins-specific parts or be able to order the spring for you.
• General Online Marketplaces: Beyond eBay, there are other general online marketplaces worth exploring, such as Amazon or Alibaba. These sites offer a vast array of products, and you may be able to find the spring or an equivalent option.

When purchasing online, ensure that you are buying from a reputable source and that the part is compatible with your specific Cummins 855 engine configuration. It's always a good idea to consult with a qualified mechanic or a Cummins technician before making any modifications to your engine.

The importance of a pyrometer when increasing fuel pressure

The 855 Cummins engine is a powerful piece of machinery, but it's important to remember that with great power comes great responsibility. When increasing fuel pressure, it's crucial to have a pyrometer installed to monitor your exhaust gas temperatures (EGTs). Here's why:

• Exhaust Gas Temperatures (EGTs): The high amount of heat produced by an engine can cause exhaust temperatures to reach nearly 2,000 degrees Fahrenheit under a heavy load. A pyrometer is a temperature gauge designed to monitor these EGTs, which can rapidly increase to over 1,000 degrees in seconds during extreme acceleration or heavy loads.
• Preventing Engine Damage: Most vehicle engines use aluminum in essential components like pistons, exhaust manifolds, and engine heads. Aluminum has a melting point of just over 1,220 degrees Fahrenheit. Extended periods at temperatures above 1,300 degrees can diminish the life of your engine, and anything over 1,500 degrees can cause immediate damage, such as melted pistons or internal engine failure. A pyrometer allows you to monitor these temperatures and take action before damage occurs.
• Optimizing Fuel Economy: Monitoring EGTs with a pyrometer can also help optimize fuel economy. High EGTs can be caused by excessive fuel or a lack of air. By monitoring these temperatures, you can adjust your fuel usage to stay within the ideal operating range, resulting in better fuel efficiency and less wear on your engine.
• Early Warning System: A pyrometer acts as an early warning system, alerting you to potentially damaging situations before they cause serious engine trouble. This is especially important in turbo-diesel vehicles, where EGTs can get too high without any warning to the driver, leading to costly repairs.
• Accurate Temperature Measurement: The pyrometer's sensing probe is mounted in the exhaust manifold or immediately after the turbine outlet of the turbocharger, providing an accurate measurement of EGTs. This allows you to take immediate action if temperatures start to climb too high.
• Engine Performance: By keeping EGTs in check with a pyrometer, you can safely increase fuel pressure and fine-tune your engine's performance. This balance between power and temperature control ensures that you get the most out of your engine without sacrificing reliability.

In conclusion, when increasing fuel pressure in your 855 Cummins engine, a pyrometer is an essential tool for monitoring EGTs and preventing engine damage. It also helps optimize fuel economy and enhances your overall engine performance. Remember to always exercise caution when modifying fuel pressure and to regularly monitor your engine's vital signs to ensure a long and healthy life for your vehicle.

The risks of increasing fuel pressure

The 855 Cummins engine can be modified to increase horsepower and fuel pressure. This can be done by changing the fuel button, adding shims, or adjusting the throttle shaft screw. However, it is important to understand the risks associated with increasing fuel pressure.

Increasing fuel pressure can lead to a range of issues, from reduced performance to severe engine damage. Here are some of the risks associated with increasing fuel pressure:

• Overfuelling: When fuel pressure is too high, the engine can be overfuelled, resulting in rough engine operation, poor fuel economy, and black smoke from the exhaust.
• Engine damage: Consistently high fuel pressure can lead to engine damage, including piston damage and valve float. This can result in costly repairs or even require a complete engine replacement.
• Reduced fuel efficiency: High fuel pressure can disrupt the air-fuel ratio, leading to inefficient combustion and increased fuel consumption.
• Poor vehicle performance: Low fuel pressure affects acceleration and power output, resulting in sluggish performance and stalling. This can compromise driving safety, especially in heavy traffic or on highways.
• Safety hazards: Inconsistent fuel delivery due to low fuel pressure can cause unexpected stalling, increasing the risk of accidents. Additionally, damaged or leaking fuel lines pose a serious fire hazard.
• Misfires and rough idling: Low fuel pressure can cause engine misfires and rough idling due to insufficient fuel supply to the engine.
• Increased emissions: Inefficient combustion due to high fuel pressure can lead to increased emissions, impacting the environment negatively.
• Catalytic converter damage: High fuel pressure can cause unburned fuel to enter the exhaust system, damaging the catalytic converter over time.
• Fuel system strain: Increasing fuel pressure puts additional strain on the fuel pump, fuel lines, and injectors, potentially reducing their lifespan and leading to costly repairs.
• Void warranties: Modifying the fuel system to increase fuel pressure may void any existing warranties on the vehicle or its components.

It is important to note that these risks are not exhaustive, and increasing fuel pressure can have other negative consequences. It is always recommended to consult with a qualified mechanic or diesel technician before making any modifications to your vehicle's fuel system.

How to increase fuel pressure

There are several ways to increase fuel pressure, depending on the type of vehicle and engine. Here are some methods to increase fuel pressure in a vehicle:

• Adjusting the Fuel Pressure Regulator: The fuel pressure regulator controls the fuel pressure in the system. By modifying or replacing this component, you can increase the fuel pressure. This can be done by "squeezing" the factory fuel pressure regulator or installing an externally-regulated setup with an adjustable regulator.
• Modifying the Fuel Pump: Increasing the fuel pressure in the rails can be achieved by modifying the fuel pump or installing a higher-performance fuel pump. This can involve adjusting the stock regulator or performing a "fuel pressure mod".
• Increasing Oil Pressure: For diesel engines, increasing the oil pressure that fires the injectors can also increase fuel pressure. This can be done through modifications like the "10K Mod" or "18K Mod".
• Fuel Button/Idle Spring Plunger Adjustment: In some engines, like the Cummins 855, the fuel button or idle spring plunger can be adjusted to increase fuel pressure. A lower number fuel button delivers more fuel, increasing power output and fuel pressure. This requires removing the idle adjustment cover and replacing the button with a lower number.
• Throttle Snap Test and Adjustment: On the Cummins 855 engine, performing a throttle snap test can help determine the current fuel pressure. By quickly snapping the throttle to the full position and measuring the pressure, you can get a reference point. Adjusting the centre throttle shaft screw after this test can increase fuel pressure.
• Dual Fuel Line Modification: Installing a dual fuel line kit can increase fuel pressure and power output. This modification involves changing the fuel lines and fuel button to deliver more fuel to the engine.

It is important to note that increasing fuel pressure should be done carefully and with proper knowledge of the engine and its requirements. Adjustments to fuel pressure can impact engine performance, emissions, and fuel efficiency. It is recommended to consult with experts or mechanics familiar with the specific engine before making any modifications.

The difference between a fuel button and a fuel pressure spring

The fuel button, also known as the idle plunger, is a component of the fuel pump that regulates fuel pressure. It is located inside the bowl at the rear of the pump and can be accessed by removing the bowl and snap ring. The fuel button has a number stamped on it, which indicates the amount of fuel delivered to the engine. A lower number, such as 12, will result in more fuel being delivered, while a higher number, such as 24, will result in less fuel. Changing the fuel button can increase fuel pressure and power output, but it is important to monitor fuel pressure and engine temperature to avoid engine damage.

On the other hand, a fuel pressure spring is a separate component that works in conjunction with the fuel pump to maintain fuel pressure. The spring provides tension to the fuel pump, ensuring that it delivers the correct fuel pressure. Unlike a typical mechanical spring, a fuel pressure spring uses compressed gas contained within an enclosed cylinder to store potential energy. The GDS Fuel Pressure Spring, for example, increases fuel pressure from the stock 60-80 psi to 90-110 psi. It also has better durability, losing only 1-5% of its spring tension in 1,000,000 cycles compared to the stock spring's 25% loss in 10,000 cycles.

In summary, the fuel button is a component of the fuel pump that regulates fuel pressure by allowing more or less fuel to pass through, while the fuel pressure spring is a separate component that works with the fuel pump to maintain fuel pressure by providing tension. Both play important roles in ensuring optimal fuel pressure and engine performance.

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