Detroit Diesel 671 Non-Turbo (4-Valve Head Type) – Fresh Water Pump & Cooling System Parts Catalog

The Detroit Diesel 6-71 non-turbo engine stands as one of the most iconic powerplants ever built by Detroit Diesel, trusted for decades across marine, industrial, and stationary applications. Known for its robust two-stroke design and reliability under heavy loads, proper cooling is essential to maintaining the engine’s legendary performance.

This catalog is dedicated to all cooling system components for the Detroit Diesel 671 Non-Turbo (4-Valve Head Type), focusing on fresh water pumps, gaskets, thermostats, hoses, fittings, and other related hardware. Each part listed here is engineered to meet or exceed OEM specifications—ensuring your Detroit Diesel engine remains dependable for years to come.

Engine Cooling Overview

The cooling system on a Detroit Diesel 6-71 non-turbo engine uses a fresh water pump to circulate coolant through the cylinder block, cylinder head, and heat exchanger. This circulation maintains optimal engine temperature, preventing overheating while ensuring efficient operation under varying conditions.

Whether your 6-71 is installed in a marine vessel, a generator set, or industrial machinery, the reliability of your water pump and related components is critical. A properly functioning cooling system not only preserves engine performance but also extends component lifespan and reduces operating costs.

Detroit Diesel 6-71 Fresh Water Pumps

Right-Hand Rotation Pump

Detroit Diesel Engine Water Pump – Right Hand Rotation

• For 3-71, 4-71, and 6-71 Engines

• New, premium aftermarket replacement

• Engineered for marine, industrial, and stationary applications

• Designed for clockwise (right-hand) rotation

• Ensures precise coolant flow and optimal pressure across the block

A right-hand rotation pump is typically used on specific engine configurations based on the drive setup and accessory orientation. Diesel Pro Power supplies new pumps, not remanufactured, ensuring durability and longevity that meets or surpasses original Detroit Diesel standards.

Left-Hand Rotation Pump

Detroit Diesel Engine Water Pump – Left Hand Rotation

• For 3-71, 4-71, and 6-71 Engines

• New, left-hand rotation (counterclockwise)

• Built with high-quality seals, bearings, and impeller materials

• Perfect for reverse rotation engines or specific marine gear configurations

When determining rotation, always stand facing the pump shaft. Diesel Pro Power’s left-hand and right-hand options simplify ordering, with clear labeling and side-by-side image comparisons for easy identification.

Fresh Water Pump Components & Accessories

Pump Gaskets and Seals

Detroit Diesel Pump Gasket

• Provides a tight seal between the fuel pump and water pump interface

• Prevents coolant leaks and cross-contamination

• Precision cut for OEM-level fitment

Water Seal (2 3/16" O.D.)

• Inner lip for secure coolant containment

• Ensures watertight protection at critical junctions

Water Manifold Seals (2½" and 2¾" O.D.)

• Used between the water manifold and oil cooler housing

• Withstands pressure and temperature fluctuations common in heavy-duty use

Proper gasket and seal maintenance is essential to avoid coolant loss and contamination, both of which can lead to overheating or oil dilution.

Pump Flange

Detroit Diesel Water Pump Flange

• Internal diameter: 1.558 inches

• Provides robust connection between pump and housing

• Machined from corrosion-resistant material

A precision flange ensures tight coupling of the water pump to the engine system, maintaining proper alignment and flow integrity.

Repair Kit for Water Pump

Detroit Diesel Water Pump Repair Kit

• Compatible with both left- and right-hand rotation pumps

• Includes bearings, seals, and impeller components

• Ideal for maintenance or in-field overhauls

Rather than replacing the entire pump assembly, technicians can restore performance with a full repair kit—saving both time and cost without compromising reliability.

Thermostat & Temperature Control

Thermostat

Detroit Diesel Thermostat (173°F)

• Maintains optimal engine operating temperature

• Opens gradually at 173°F to regulate coolant flow

• Prevents overcooling and promotes efficient combustion

Proper thermostat function is key for maintaining consistent temperature and preventing thermal shock during warm-up or load changes.

Thermostat Gaskets & Housing Components

Thermostat Gasket and Housing Gasket

• Ensures tight, leak-free seal at thermostat housing

• Made from high-temperature materials to resist deformation

Thermostat Connection Tube (Water Bypass)

• Directs coolant from thermostat housing to water manifold

• Ensures continuous circulation even when thermostat is closed

By maintaining bypass flow, this system helps the Detroit Diesel 6-71 warm up evenly, preventing localized hot spots or cold zones within the engine block.

Radiator & Related Components

Radiator Assembly

Detroit Diesel Industrial Radiator for 3-71, 4-71, 6-71 Engines

• Designed for stationary or truck-mounted engines

• Heavy-duty core construction

• Optimized fin spacing for maximum heat dissipation

A reliable radiator complements the fresh water pump, ensuring complete thermal regulation for engines operating in demanding environments.

Radiator Caps & Necks

Radiator Cap – 7 PSI Pressure Rating

• Controls system pressure to prevent boiling

• Compatible with Detroit Diesel 71 Series radiators

Small and Large Radiator Necks

• Available in multiple diameters for exact fitment

• Precision-machined for secure cap seating

Maintaining the proper radiator cap pressure ensures your cooling system operates efficiently, avoiding both overpressure and air intrusion.

Radiator Cleaner

Detroit Diesel Radiator Cleaner (18E)

• Removes scale, sludge, and deposits from cooling passages

• Restores optimal heat transfer efficiency

• Recommended for periodic system maintenance

Available for ground shipping within the U.S. and Canada, this cleaner keeps your cooling system in peak condition.

Drain Fittings & Cocks

Draincock Fittings – 1/4" and 3/8"

• Allows controlled draining of coolant for maintenance

• Precision-threaded brass fittings resist corrosion

• Essential for marine and industrial engines during seasonal service

Coolant Hoses & Clamps

Silicone Coolant Hoses

Available in multiple diameters:

• ¾", 1", 1¾", 1⅞", 2", 2⅛", 2¼", 2⅜", 2½", 2¾", 3", 3½", and 4"

• Each hose is 1 foot long, with superior heat and pressure resistance

• Silicone construction resists cracking, swelling, and coolant degradation

These hoses are suitable for coolant, antifreeze, and water lines, ensuring dependable flow under sustained high-temperature operation.

Hose Clamps

A full selection of premium clamps ensures secure hose installation and leak prevention.

• Small-Diameter Clamps (9/16"–1-1/16") – Ideal for smaller coolant and fuel hoses

• Medium Clamps (1"–1.5") – For general-purpose cooling connections

• Large Clamps (2⅜"–3½") – Heavy-duty marine and industrial applications

Each clamp is corrosion-resistant and engineered to maintain consistent tension, even after repeated thermal cycling.

Gauges & Monitoring Components

Mechanical & Electric Gauges

• Available in 12V and 24V configurations

• Includes alarm-compatible options for overheat protection

• Ensures accurate real-time monitoring of coolant temperature and system performance

Adding or upgrading gauges helps operators detect cooling issues early, preventing costly repairs and unplanned downtime.

Temperature Switch

Temperature Switch for Detroit Diesel Engines

• Activates at 205°F

• Thread: ½" NPT

• Compatible with Detroit Diesel, Cummins, and Caterpillar engines

A vital safeguard in modernized systems, this switch triggers alarms or shutdowns when coolant temperature exceeds safe limits.

Finishing Components & Accessories

Detroit Diesel Green Engine Paint

• Authentic Detroit Green color

• Protects metal surfaces from corrosion and heat

• Perfect for restoring vintage or rebuilt 6-71 engines

Maintaining the distinctive Detroit Diesel look helps protect components while preserving the historical authenticity of these engines.

Understanding Water Pump Rotation

Determining rotation direction is critical before ordering your water pump.

• Right-Hand Rotation: Clockwise when facing the pump shaft.

• Left-Hand Rotation: Counterclockwise when facing the pump shaft.

Selecting the wrong rotation can cause reverse coolant flow, overheating, and system failure. Diesel Pro Power provides visual comparison charts to confirm correct rotation before purchase.

Maintenance & Replacement Tips

• Inspect annually for leaks or corrosion around pump seals and gaskets.

• Replace thermostats every two years or as part of major overhauls.

• Flush cooling system periodically using radiator cleaner to remove scale and contaminants.

• Use silicone hoses for superior longevity compared to standard rubber.

• Verify pressure ratings on radiator caps to match your cooling system’s design.

A well-maintained cooling system ensures that your Detroit Diesel 6-71 continues operating efficiently and reliably for thousands of hours.

Why Buy Detroit Diesel 6-71 Fresh Water Pump & Cooling System Parts from Diesel Pro Power

Choosing the right supplier is as vital as choosing the right component. Diesel Pro Power is the global leader in Detroit Diesel replacement parts for a reason:

Proven Global Reputation – Trusted by over 40,000 customers in more than 180 countries, Diesel Pro Power is recognized as the premier source for Detroit Diesel components.

Premium Aftermarket Quality – Every water pump, gasket, seal, hose, thermostat, and accessory meets or exceeds OEM engineering standards.

Comprehensive Catalog – Organized by engine model and system for fast, accurate part identification, ensuring you order exactly what your 6-71 engine requires.

Fast Worldwide Shipping – Minimize downtime with reliable delivery to ports, marinas, industrial sites, and remote operations around the globe.

Expert Technical Support – Diesel Pro specialists provide personalized guidance on selecting the correct pump rotation, gasket configuration, thermostat compatibility, and coolant hose sizing.

Customer-First Service Philosophy – From order placement to delivery, Diesel Pro Power ensures every customer receives prompt, professional support.