Caterpillar D343 Raw Water Pump & Marine Cooling System Parts Catalog

The Caterpillar D343 marine engine is a proven powerhouse, widely relied upon in heavy-duty marine applications including commercial vessels, workboats, and offshore support fleets. To keep this engine running at peak efficiency, a properly functioning raw water pump and complete cooling system are essential. Saltwater introduces unique challenges such as corrosion, scale buildup, and constant wear, which makes the selection of durable aftermarket pumps, impellers, anodes, hoses, and clamps critical.

Diesel Pro Power provides a complete aftermarket solution for Caterpillar D343 operators worldwide. With over 40,000 satisfied customers across 180+ countries, our marine-focused catalog ensures every operator can source reliable water pumps and cooling components quickly, minimizing downtime and extending engine life.

Marine Water Pump for Caterpillar D343

At the heart of the D343 cooling system lies the raw water pump. This heavy-duty pump draws seawater into the engine’s cooling system, circulating it through heat exchangers before discharging it overboard. The pump ensures that engine temperatures remain stable under heavy load, whether the vessel is maneuvering at low speed in a harbor or pushing full power offshore.

• Heavy-Duty Bronze Construction – Built to resist the corrosive effects of saltwater.

• Durable Cam Liner – Provides smooth, efficient impeller operation, reducing wear.

• Precision Fit for Caterpillar D343 – Ensures compatibility with the original cooling layout.

• Aftermarket Alternative – Provides a cost-effective, reliable solution compared to OEM-only options.

This pump is also commonly used across related Caterpillar models such as the D336 and D353 series, making it a versatile option for operators with mixed fleets.

Impellers for Caterpillar D343 Water Pumps

Impellers are the moving force behind raw water circulation. These rubber or bronze-fitted components rotate inside the pump housing, pulling seawater into the system and delivering steady flow. Regular inspection and replacement of impellers is one of the most important maintenance steps for preventing cooling system failures.

• 12-Blade Configuration – Designed for optimal seawater flow.

• Double Flat Drive – Ensures positive engagement and long service life.

• Durable Material – Withstands constant exposure to salt, sand, and marine growth.

• Correct Dimensions – Sized specifically for the Caterpillar D343 pump housing.

Replacing impellers at regular intervals—typically annually or at the first signs of wear—helps avoid overheating and costly downtime.

Zinc Anodes for Caterpillar D343

Saltwater environments create galvanic corrosion, a natural electrochemical process that can eat away at metal components in the cooling system. Zinc anodes act as sacrificial protectors, corroding in place of more critical components such as pump housings and heat exchangers.

Our catalog includes a full range of zinc anodes in multiple sizes and thread types, all compatible with the Caterpillar D343 marine engine cooling system.

• Threaded Designs – Available in NPT sizes from 1/4” up to 1 1/4”.

• Various Lengths & Diameters – Ensures coverage for different placements in the cooling circuit.

• Marine-Grade Zinc – Provides maximum corrosion protection.

• Easy Replacement – Quick-thread design makes routine maintenance simple.

Routine inspection and replacement of zincs is a low-cost maintenance step that prevents expensive repairs to the raw water pump and associated cooling parts.

Marine Silicone Coolant Hoses

Silicone coolant hoses provide flexible, high-temperature-resistant connections throughout the D343 cooling system. Unlike traditional rubber hoses, silicone offers superior resistance to cracking, swelling, and saltwater intrusion.

We carry a wide selection of silicone hoses for Caterpillar D343 cooling systems:

• Inside diameters ranging from 1” up to 4”.

• Supplied in 1-foot lengths for easy replacement.

• Designed for marine-grade durability under high-pressure circulation.

• Resistant to heat, saltwater, and oil contamination.

Using silicone hoses helps reduce leaks and keeps the raw water pump system running efficiently.

Hose Clamps for Caterpillar D343 Cooling System

A hose is only as strong as the clamp that secures it. Marine-grade hose clamps ensure that coolant and seawater connections remain sealed, even under vibration and pressure fluctuations.

Our aftermarket clamp catalog includes multiple diameter ranges to cover every hose size in the Caterpillar D343 system:

• Adjustable ranges from under 1” up to over 3”.

• Stainless steel construction for superior corrosion resistance.

• Smooth band designs that prevent hose damage.

• Easy installation and tightening, even in confined spaces.

By pairing silicone hoses with the right clamps, operators ensure leak-free reliability across the entire cooling system.

Why Proper Cooling Maintenance Matters for the D343

The Caterpillar D343 is known for its durability, but without proper cooling, even the most reliable engine can fail. Marine engines operate in a harsh environment where high power loads and continuous exposure to seawater create unique challenges. A compromised raw water pump or a corroded zinc can quickly lead to overheating, cylinder damage, or costly rebuilds.

Regular maintenance of water pumps, impellers, hoses, and zincs is essential to protect:

• Engine Longevity – Preventing overheating ensures the D343 reaches its full service life.

• Fuel Efficiency – Engines running at stable temperatures burn fuel more cleanly.

• Reduced Downtime – Proactive maintenance avoids unexpected failures at sea.

• Lower Costs – Replacing inexpensive components like zincs and impellers prevents major repair expenses.

Why Choose Diesel Pro Power for Caterpillar D343 Raw Water Pumps

Diesel Pro Power has built its reputation as the leading aftermarket supplier for Caterpillar marine engines, including the D343. For decades, vessel operators have relied on our expertise, fast service, and dedicated focus on heavy-duty marine engines to keep their operations running smoothly. Choosing the right supplier is just as important as choosing the right pump, and here’s why operators around the world trust us:

• 40,000+ Satisfied Customers Worldwide – From large commercial shipping companies to small fishing operations and private yacht owners, our customer base spans every corner of the marine industry. The consistent trust of such a broad range of operators highlights our proven reliability.

• Shipping to Over 180 Countries – Whether your vessel is docked in a major port city or operating in a remote region, Diesel Pro Power ensures quick and trackable delivery. Fast shipping reduces downtime, allowing you to get your Caterpillar D343 back in service without costly delays.

• Complete Marine Catalog in One Place – More than just raw water pumps, we provide the full range of related components: impellers, zinc anodes, silicone hoses, clamps, gaskets, gauges, and other essential parts. This one-stop solution makes maintenance simpler by eliminating the need to source parts from multiple suppliers.

• Exclusive Marine & Industrial Focus – Unlike general distributors who divide attention between automotive, construction, and consumer markets, Diesel Pro Power is entirely dedicated to marine and heavy industrial engines. This specialization ensures that every Caterpillar D343 part we supply is selected with demanding marine conditions in mind.

• Expert Technical Support – Our team doesn’t just ship parts; we help solve problems. Need guidance on impeller sizing, zinc replacement intervals, or raw water pump troubleshooting? Our knowledgeable staff is ready to provide detailed support tailored specifically to your engine.

By sourcing your Caterpillar D343 cooling system parts from Diesel Pro Power, you’re choosing a supplier that combines global reach with marine-specific expertise. The result is more than just reliable parts—it’s a partnership that keeps your vessel operating at peak efficiency, reduces long-term maintenance costs, and delivers confidence every time you head to sea.