Engine Water Pump

Cummins 4BT Engine Parts – Fresh Water Pump and Cooling System Catalog

The Cummins 4BT is one of the most widely trusted 4-cylinder diesel engines, valued for its simplicity, compact design, and long-lasting performance across marine, industrial, and off-highway applications. Whether you're powering a commercial vessel, an irrigation pump, or a stationary generator, keeping the 4BT engine’s temperature under control is critical to avoiding catastrophic failures and preserving engine longevity.

At Diesel Pro Power, we offer a complete catalog of Cummins 4BT fresh water pump and cooling system components, ready to ship with fast delivery and supported by more than 40,000 satisfied customers worldwide.

Engine Water Pump for Cummins 4BT

Premium Direct-Fit Fresh Water Pump

Our Cummins 4BT engine water pump is designed to replace the OEM unit with precision fit and performance. This is a belt-driven centrifugal water pump that circulates coolant throughout the block and cylinder head, supporting consistent engine temperatures even in high-load or high-temperature environments.

Key Features:

Direct replacement for B-series engine water pumps
Cast housing with corrosion-resistant coating
Sealed impeller design to prevent coolant leakage
Designed to fit CPLs including: 1975, 2122, 2292, 2686, 2893, 8039, 2071, 8239, 2208, 8444, 2264, and many more
Suitable for both marine cooling configurations (with heat exchangers) and closed-loop industrial applications

If your 4BT-powered application is overheating, leaking coolant, or showing signs of bearing wear (whining or vibration), replacing the water pump is one of the first steps toward restoring full performance.

Cummins 4BT Water Pump Seal Ring

A failed seal ring is one of the most common culprits behind coolant leaks. Our replacement seal ring provides a tight and lasting fit for Cummins 4BT engines. Designed to resist coolant chemicals, pressure, and temperature cycling, this component is an essential part of any water pump installation or repair.

Made from high-performance elastomer compounds
Sized precisely to OEM specifications
Compatible with 4B, 4BT, and B-series water pump housings

Cummins 4BT Thermostats

Thermostats regulate when coolant flows to the radiator or heat exchanger, keeping your engine operating within its ideal temperature range. We carry multiple thermostat configurations to match your operating environment and application requirements.

165°F Thermostat

This lower-temperature thermostat is ideal for marine engines, gensets in warm climates, or any application where overheating risk is high.

Opens at 165°F (74°C)
Speeds up coolant flow in hot engine bays
Common for boats, forklifts, and turbocharged configurations

180°F Thermostat

Designed for standard industrial operating conditions.

Opens at 180°F (82°C)
OEM-equivalent performance
Balances quick warm-up and thermal efficiency

Thermostat Seals and Gaskets

No thermostat installation is complete without a proper sealing solution. Diesel Pro Power carries premium-quality seals and gaskets for Cummins 4BT engines:

Thermostat Housing Gasket – Prevents leaks between housing and cylinder head
Thermostat Seal Ring – Ensures tight seating around the thermostat body

Our gaskets are manufactured from composite or elastomeric materials engineered to handle long-term exposure to heat, pressure, and coolant additives.

Belt Tensioners for Cummins 4BT

The belt tensioner maintains consistent drive tension across the water pump, alternator, and fan pulleys. We offer both plain and grooved pulley options to match your belt configuration:

Options Include:

Plain Pulley Tensioner – For smooth-belt or low-load setups
Grooved Pulley Tensioner – For serpentine-style belts with high grip requirements

All tensioners are spring-loaded for automatic adjustment and built with sealed bearings for maximum durability.

Serpentine Drive Belts for Water Pump, Fan, and Alternator

Your Cummins 4BT relies on serpentine belts to operate its water pump, alternator, and radiator fan (or marine coolant pump). We offer a full range of 8-rib V-belts in sizes ranging from 53.5” to 69”.

Belt Details:

Ribbed for maximum grip and efficiency
Width: 1.125”
Resistant to heat, oil, and abrasion
Backed by OEM specifications for length and tension compatibility

Available Lengths:

53.50", 57.5", 59", 59.5", 60", 66.53", 66.92", 69.0"

Whether you're working on a 4BT-powered welder, pressure washer, vessel, or crane, we have the correct belt length to keep your accessory drive operating smoothly.

Radiator & Heat Exchanger Cleaners

Cooling efficiency is critical to 4BT engine life. Scale, rust, and mineral deposits can clog heat exchangers or radiator cores, impeding coolant flow and thermal transfer.

Our radiator cleaner is specially formulated for diesel cooling systems. It's safe for use with copper, brass, and aluminum and helps restore full cooling performance without damaging your system.

Removes internal deposits
Reduces operating temperatures
Compatible with Cummins and Detroit Diesel systems

Temperature Switch for Cummins 4BT

The engine temperature switch activates alarms or shutdown signals when coolant temperatures exceed safe thresholds. This is critical for preventing damage in unmanned or remote applications.

Set to close at 205°F
Thread: 1/2" NPT
Fits Cummins 4B, 4BT, ISB, and other compatible diesel engines

Ideal for marine engines or remote generators requiring thermal safety sensors.

Silicone Coolant Hoses for Cummins 4BT

Cummins 4BT engines use a series of coolant hoses to route fluid between the water pump, block, thermostat housing, radiator, and more. Our hoses are made of multi-layer silicone to resist collapsing, cracking, or chemical degradation.

Available Inner Diameters (ID):

3/4", 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 by the foot and offers superior flexibility and temperature resistance. Perfect for marine installations, enclosed gensets, or applications with tight bends.

Stainless Steel Hose Clamps

Secure every hose connection in your cooling system with high-grade hose clamps. These are made for long-lasting performance under vibration, pressure, and thermal cycling.

Clamp Sizes Include:

9/16” to 1-1/16”
1” to 1.5”
11/16” to 1-1/4”
1-5/16” to 2-1/4”
2-5/16” to 3.0”
2-7/8” to 3.5”

All clamps are adjustable, corrosion-resistant, and suitable for both coolant and fuel hose connections.

Comprehensive Cooling System Overhaul for Cummins 4BT

If you're planning a complete 4BT cooling system service, we recommend inspecting and potentially replacing the following components:

Fresh Water Pump – Core of the cooling loop; must be leak-free and have good bearings
Thermostat and Seal – Controls coolant temperature and flow
All Coolant Hoses – Check for bulges, softness, or cracks
Tensioner and Belts – Look for uneven wear, squealing, or glazing
Clamps – Replace corroded or seized clamps to prevent hose failures
Coolant and Flush Additives – Remove rust and deposits with a system cleaner before refilling

This full-system approach is especially critical for marine applications where engine overheating may result in serious damage or inaccessibility of the equipment during operation.

Popular CPL Coverage for 4BT Cooling Parts

The parts listed in this catalog are compatible with dozens of Cummins CPLs (Critical Parts Lists) commonly found in 4BT-powered applications:

Marine CPLs: 8039, 8444, 8208, 8236, 8239
Industrial CPLs: 2071, 2292, 2243, 2109, 2264, 2372, 2530
Legacy & OEM CPLs: 741, 1268, 1522, 1523, 1524, 1525, 1962, 1965, 1967

Always verify your CPL to ensure correct compatibility. If in doubt, contact Diesel Pro Power’s support team—we’re here to help.

Why Diesel Pro Power?

Trusted by 40,000+ customers worldwide
Fast shipping from a centralized U.S. warehouse
Exclusive stock of hard-to-find Cummins 4BT cooling parts
Bilingual support in English and Spanish
Deep experience with marine and industrial diesel applications

When you order from Diesel Pro, you’re not just buying a part—you’re getting the assurance of tested reliability, excellent customer service, and accurate fitment guidance.