Cummins QSL Engine Water Pump & Cooling System Parts Catalog

Diesel Pro Power proudly offers an extensive selection of freshwater pump and cooling system components for Cummins QSL engines. Whether you’re performing routine maintenance or a full engine rebuild, having a reliable water pump and properly functioning coolant system is critical to the longevity and performance of your QSL engine. Our parts are compatible with numerous CPL numbers and offer the durability trusted by over 40,000 satisfied customers around the world.

Engine Compatibility and CPL Coverage

Our Cummins QSL water pump and cooling system parts are designed for compatibility with a wide range of CPL (Control Parts List) numbers. Supported CPLs include:

2964, 8641, 1754, 3301, 8647, 1404, 1096, 8221, 8389, 8458, 8220, 8627, 8630, 3212, 2, 2693, 2694, 2695, 2691, 2237, 2946, 2475, 422, 8695, 8693, 8648, 401, 8650, 400, 8478, 8538, 8639, 8636, 8537, 8153, 8152, 8151, 8780, 8697, 8730, 8692, 8159, 8056, 1632, 2722, 8746, 1738, 1793, 1286, 8703, 8185, 2997, 8307, 2996

Whether your engine is powering a marine vessel or industrial application, Diesel Pro Power ensures consistent fit and top-tier quality.

Cummins QSL Engine Water Pump

Premium-Grade Freshwater Pump Assembly

The water pump is the heart of your Cummins QSL cooling system. It circulates coolant through the engine block, cylinder head, and radiator, preventing overheating and ensuring efficient thermal regulation.

Our Cummins QSL engine water pump:

• Is fully compatible with ISC, QSC, ISL, and QSL platforms
  
  

• Fits a broad range of CPLs
  
  

• Comes ready for installation with precision-balanced impellers and durable bearings
  
  

• Built to OEM-equivalent standards or better
  
  

This direct-replacement pump restores original engine cooling performance and is ideal for scheduled maintenance or urgent repair.

Cummins QSL Thermostat

Maintain Ideal Engine Temperature

The thermostat is a key regulator of coolant flow. Our Cummins QSL thermostats are designed to open at 180°F, allowing coolant to circulate at the optimal temperature range for efficient engine operation.

Key features:

• Supports ISC, ISL, QSC, and QSL platforms
  
  

• Durable construction for high heat cycles
  
  

• Prevents engine overcooling or overheating
  
  

• Compatible with all pump assemblies and coolant system hoses sold on this page
  
  

Serpentine Drive Belts for Water Pump, Alternator & Fan

High-Strength Belts for Accessory Drive Systems

A serpentine belt connects the water pump to other essential components such as the alternator and engine fan. Diesel Pro Power offers multiple belt sizes to fit various QSL engine configurations:

• Ribbed 8-rib design for optimal grip and minimal slippage
  
  

• Available lengths: 53.5" to 69.0"
  
  

• Width: 1.125" standard across all belt options
  
  

• Engineered for long-lasting performance and resistance to cracking
  
  

Each belt is listed by length to ensure compatibility with your engine setup and accessory positioning.

Temperature Switches for QSL Engines

Temperature Sensing for Critical Monitoring

Our temperature switches are precision-calibrated to close at 205°F. These switches can be used in Cummins, Detroit Diesel, and Caterpillar engines and feature:

• 1/2” NPT thread for universal fit
  
  

• Accurate temperature readings for alarms or fan engagement
  
  

• Reliable switching mechanism built for marine and industrial environments
  
  

Installing a high-quality temperature switch is essential for automated engine protection and effective coolant flow monitoring.

Cummins QSL Coolant Hoses (Silicone)

Heavy-Duty Silicone Hoses in Multiple Sizes

Silicone coolant hoses provide flexibility and heat resistance superior to rubber hoses. We offer a complete range of inside diameters from 3/4" to 4", all in 1-foot lengths, to fit any section of your Cummins QSL coolant circuit.

Available diameters include:

• 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 manufactured with reinforced silicone to resist bursting under pressure and endure extreme engine heat.

Hose Clamps for QSL Cooling System

Secure Your Hoses with Premium Clamps

Without high-quality clamps, even the best coolant hose can leak under vibration or pressure. Our clamp selection covers a wide range of diameters and includes:

• Standard worm gear clamps
  
  

• Adjustable for various hose sizes
  
  

• Rust-resistant and suitable for high-moisture environments
  
  

• Effective for both coolant and fuel hose applications
  
  

Clamp sizing ranges include:

• From 9/16" to 1 1/16"
  
  

• Up to 2 7/8" to 3 1/2"
  
  

• Everything in between for precise fitment
  
  

These clamps are compatible with all silicone hoses in our catalog and are essential for a leak-free installation.

Radiator Cleaner for Cummins Cooling System Maintenance

Protect Your Water Pump and Coolant Lines

Over time, scale and deposits from coolant or hard water can accumulate in your QSL’s radiator and passageways. This buildup impedes water pump efficiency and can lead to overheating. Our radiator cleaner:

• Restores coolant system flow
  
  

• Removes rust, lime, and debris from internal surfaces
  
  

• Compatible with all Cummins QSL and related engines
  
  

• Easy-to-use formulation for regular maintenance
  
  

Keeping your coolant system clean helps protect your engine's water pump, thermostat, belts, and hoses from premature failure.

Cooling System Maintenance Best Practices for Cummins QSL Engines

How to Extend the Life of Your Water Pump & Coolant System

Maintaining the QSL engine cooling system is essential for optimal performance, whether in a stationary generator or marine propulsion system. Follow these practices:

• Flush coolant every 2,000–3,000 hours or per manufacturer recommendations
  
  

• Inspect belts and hoses at every oil change for signs of wear or cracking
  
  

• Replace the thermostat regularly to ensure accurate temperature regulation
  
  

• Monitor coolant levels and pressure using electric or mechanical gauges
  
  

• Use only distilled or deionized water with recommended antifreeze mixtures
  
  

Routine service keeps your engine at optimal operating temperature, reduces wear on moving parts, and avoids costly overheating failures.

Why Choose Diesel Pro Power for Cummins QSL Cooling Parts?

Trusted by 40,000+ Customers Worldwide

At Diesel Pro Power, we specialize in Cummins engine parts for marine and industrial applications. Our cooling system components for the QSL series are:

• Engineered for OEM fit and durability
  
  

• Backed by fast shipping and expert customer support
  
  

• Ready to ship from a fully stocked inventory
  
  

• Offered with a satisfaction guarantee
  
  

We’ve helped thousands of marine operators, commercial equipment owners, and fleet managers extend engine life and reduce downtime.

Related Components for a Complete Cooling System Overhaul

If you're replacing your QSL water pump, it’s often wise to inspect or replace these related components:

• Fan clutches and pulleys – Ensure the cooling fan engages at the right temperature and maintains RPM
  
  

• Coolant reservoir tank – Check for cracks and sediment buildup
  
  

• Radiator cap – A weak cap can lower system pressure and reduce boiling point
  
  

• Coolant temperature sensors – Vital for ECU-controlled engines with fault monitoring
  
  

• Expansion plugs (freeze plugs) – Should be inspected during major service or rebuilds
  
  

Replacing these parts together ensures consistent coolant flow, pressure retention, and thermal efficiency throughout the engine.