Cummins NT855 Engine Parts for Canada - Marine Water Pump Section

Marine Raw Water Pumps & Cooling System Components for Cummins NT855 Engines

The Cummins NT855 engine is a workhorse in marine propulsion and auxiliary generator applications, widely appreciated for its durability and high-performance operation. Keeping the NT855 running at peak efficiency requires a properly functioning marine raw water pump system and a fully integrated cooling assembly. Whether you're performing routine maintenance or a complete cooling system overhaul, Diesel Pro Power provides every essential component—engineered for direct compatibility with NT855 marine configurations.

This section provides a comprehensive overview of all major marine cooling and seawater pump components available for Cummins NT855 marine engines, including the water pump itself, impeller, thermostat, anodes (zincs), silicone coolant hoses, strainers, and clamps.

Raw Water Pump for Cummins NT855 Marine Engines

A fully operational raw water pump is central to maintaining safe operating temperatures in marine engines. The raw water pump used in Cummins NT855 engines is designed for bidirectional rotation—meaning it can operate with either left-hand or right-hand engine rotation, offering maximum versatility for inboard propulsion setups.

• Pump Rotation: Bidirectional (clockwise or counter-clockwise)

• Port Type: 1 1/4" hose connections

• Pulley Included: Yes

• Marine Application: Designed for saltwater operation with corrosion-resistant construction

This pump is compatible with Cummins 855 series marine platforms, including NH and VT derivatives commonly found in commercial vessels and workboats. Its robust housing and impeller design allow it to maintain steady flow rates under the high-load demands of marine propulsion.

Impeller for Cummins NT855 Raw Water Pumps

A high-quality impeller ensures that the raw water pump maintains optimal flow rates, even in harsh marine environments. The impeller compatible with Cummins NT855 marine pumps is a double flat shaft design, ensuring secure attachment and long-lasting reliability.

• Shaft Type: Double flat

• Height: 3.74 inches

• Width: 2.48 inches

• Inside Diameter: 0.98 inches

• Material: Marine-grade rubber composite for flexibility and durability

Replacing the impeller on a regular schedule—typically once per season—is essential for preventing overheating, especially in saltwater environments where deposits and wear are more aggressive.

Thermostats for Cummins NT855 Marine Engines

The NT855 engine supports two primary thermostat configurations depending on whether the engine is a standard or Big Cam variant. Maintaining the correct thermostat temperature ensures optimal coolant regulation and prevents engine overheating or thermal inefficiency.

180°F Thermostat

• Recommended for standard NT855 and NH855 marine engine configurations

• Provides consistent engine warm-up and coolant regulation

• Ideal for commercial marine settings where long run times are expected

185°F Thermostat (Big Cam Only)

• Specifically designed for Big Cam NT855 variants

• Offers slightly higher operating temperature for better fuel efficiency under heavy marine loads

• Designed for use in modernized NT855 marine retrofit builds

Both thermostat options feature marine-grade construction and corrosion-resistant housings, providing long-lasting reliability in salt-laden environments.

Marine Anodes (Zincs) for NT855 Heat Exchangers and Coolers

Zincs are crucial sacrificial components that prevent galvanic corrosion inside the engine’s heat exchanger, fuel cooler, and oil cooler assemblies. Marine engines like the NT855 require properly sized and placed zincs to preserve cooling system integrity.

Zinc for Heat Exchanger and Aftercooler

• Fits both Cummins and Detroit Diesel marine heat exchangers

• Compatible with 1/2" NPT brass plugs

• Zinc length: 2 inches

• Designed to protect aftercooler passages and internal piping

Zinc for Fuel and Oil Coolers

• Fits 3/8" NPT brass plugs

• Zinc length: 1 inch

• Recommended for NT855 fuel cooling systems and integrated oil cooler chambers

Routine replacement of these zincs during maintenance intervals can prevent extensive internal corrosion and prolong the life of expensive cooling system components.

Marine Intake Water Strainers for NT855 Cooling Systems

Strainers prevent debris, silt, and marine life from entering the raw water circuit and damaging the raw water pump or clogging internal coolant passages. Diesel Pro Power offers a complete range of marine-grade water strainers that integrate directly into the sea water intake line.

Available Sizes:

• 1" Pipe Size

• 9.5" height, 5.5" width

• Ideal for light-duty marine genset systems with Cummins NT855

• 1.5" Pipe Size

• 11.5" height, 7.25" width

• Best for standard NT855 propulsion engines

• 2" Pipe Size

• 16" height, 7.5" width

• Suitable for high-flow installations or twin engine builds

• 2.5" Pipe Size

• 16" height, 7.5" width

• Designed for large vessels using oversized sea strainers

Each strainer is constructed with corrosion-resistant bodies and comes with removable screens for easy cleaning and maintenance in confined engine rooms.

Silicone Coolant Hoses for Cummins NT855

Durable silicone hoses are essential for transferring coolant throughout the engine and heat exchanger loop. Diesel Pro Power offers high-grade silicone hoses for Cummins NT855 engines in various inner diameters to fit different cooling passages and port sizes.

Available Inner Diameters:

• 1"

• 1 3/4"

• 1 7/8"

• 2"

• 2 1/8"

• 2 1/4"

• 2 3/8"

• 2 1/2"

• 2 3/4"

• 3"

• 3 1/2"

• 4"

Each hose is sold in 1-foot lengths and offers excellent resistance to high temperature, saltwater exposure, and vibration. The hoses are compatible with both seawater and coolant, making them ideal for marine applications.

Hose Clamps for Marine Water & Coolant Systems

Secure hose connections are vital in marine environments, where vibration and heat can quickly loosen fittings. Diesel Pro Power supplies marine-grade stainless steel hose clamps with various diameter ranges to match every hose size on the Cummins NT855 engine.

Popular Clamp Ranges:

• 9/16" to 1-1/16"

• 13/16" to 1-3/4"

• 1" to 1.5"

• 11/16" to 1-1/4"

• 1-5/16" to 2-1/4"

• 1-9/16" to 2-1/2"

• 2-5/16" to 3"

All clamps are designed to resist salt corrosion and feature reinforced threading and worm drive mechanisms for secure tightening, even in wet and high-vibration settings.

Impeller Puller Tool for NT855 Marine Pumps

An impeller puller is essential when servicing raw water pumps. The NT855-compatible puller tool allows for safe, damage-free removal of worn impellers from the pump housing.

• Protects pump housing during maintenance

• Reduces labor time

• Prevents damage to impeller hub and shaft seals

This tool is particularly valuable for operators who service their NT855 engines frequently or run in waters with high sediment or marine debris content.

Optimize Your Cooling System with Diesel Pro Power

The Cummins NT855 marine engine depends on a finely tuned water cooling system for consistent, long-term operation. Whether you're operating a fishing vessel, workboat, tug, or auxiliary generator, having the correct seawater pump, impeller, thermostats, zincs, hoses, and strainers in place makes the difference between reliable uptime and unexpected failures.

Diesel Pro Power supports over 40,000 satisfied customers worldwide and offers same-day shipping on all in-stock marine cooling system components. Every part listed here is carefully selected for compatibility with the NT855 marine platform and its NH855 variants.