Kubota D722 D902-Compatible Water Pump – Overhaul Component

Matched Gasket Included — Gasket 16871-73430 ships in the same box, preventing the block from sitting open while you source a forgotten seal.

Technical Specifications

Application Suitability

When the Rebuild Stalls Waiting for a Ten-Dollar Seal

A water pump replaced without its matched gasket or without addressing the thermostat often returns to the bay within a month.

I have walked onto desert job sites where a machine was already pulled apart for a cooling system service, the block sitting exposed to dust because the overhaul kit was missing a single heat-resistant gasket. That small omission cost the crew three weeks of downtime while the part was shipped in separately. The same thing happens in engine rebuild shops when the water pump for Kubota D722 D902 engine rebuild arrives, but the mating flange gasket 16871-73430 was never listed on the quote. Addressing the system, rather than just the failed component, is how you stop comeback repairs [NEED_CITE: cooling system failure root cause analysis for small displacement diesels].

The Cooling Circuit Context for D722 and D902 Engines

This water pump sits at the heart of the Kubota D722 and D902 cooling system. It circulates coolant through the block and cylinder head to maintain operating temperature under the heavy thermal loads typical of tractor and utility vehicle use. When a pump begins to fail—usually through bearing wear or impeller erosion—the resulting overheating can warp cylinder heads and blow head gaskets, escalating a routine replacement into a major teardown.

Superseded Numbers and Serial Variants

Part numbers 1E051-73036 and 1E051-73510 appear as cross-references across different production runs of the D722 and D902 platform. Which number applies to your specific engine depends on the serial range and the variant of the block casting. Installing the wrong variant leads to port misalignment or incorrect bolt patterns. Verifying your engine serial before ordering eliminates the risk of receiving a pump that physically cannot mate to your block [NEED_CITE: Kubota engine serial range identification for aftermarket fitment].

What the Specs Mean for Your Rebuild

The included gasket 16871-73430 uses a heat-resistant compound designed to seal the pump-to-block mating surface under sustained thermal cycling. Generic cork or paper substitutions tend to compress unevenly and develop coolant weeps after a few hundred hours. The precision-machined impeller moves coolant at the flow rate the D722/D902 block was designed for; an undersized aftermarket impeller will not trigger an immediate overheat but will allow temperatures to creep upward under sustained load. High-grade bearings support the shaft under belt tension without developing the lateral play that destroys mechanical seals.

The Cost of Skipping System-Level Diagnosis

Replacing the pump while ignoring a blocked radiator or a stuck thermostat leaves the root cause active. The new pump will circulate coolant just fine, but if the radiator passages are choked with scale, the engine will still overheat under load—and the next mechanic will blame the pump. Repeated water pump failure on D722 and D902 engines is almost always a system problem, not a parts problem. A rebuild shop that does not flush the radiator, test the thermostat, and inspect hoses before installing the new pump is setting itself up for a warranty claim [NEED_CITE: diesel engine cooling system diagnostic sequence for repeat overheating].

Why Source This Pump Through Our Engine Systems Desk

We produce selected part lines in our own facility and source the remainder from qualified ISO 9001-certified manufacturing partners, with both carrying identical quality control and warranty terms. Our technical team verifies the correct pump variant against your specific D722 or D902 engine serial before dispatch, catching superseded number conflicts early. The matched gasket is confirmed in the shipment against the pump mating flange so nothing is missing when the block is open. We support sample supply for fitment confirmation before you commit to bulk, and we stock related cooling system components—thermostats, seal kits, hose sets—under one account and one warranty.

Documentation & Verification

• Commercial invoice listing pump 1E051-73036 with matched gasket line item
• Cross-reference sheet mapping 1E051-73510 and 16871-73430 as reference only
• Dimensional inspection record confirming impeller clearance and flange flatness
• Warranty terms covering manufacturing defects for 3-12 months
• Packing photographs showing pump and gasket sealed against moisture before crating
• HS code and customs documentation support for export clearance

Installation & Rebuild Sequence

• Clean the pump mating surface on the D722/D902 block to bare metal before gasket placement
• Verify gasket 16871-73430 orientation matches the coolant passage ports on your specific block variant
• Torque pump mounting bolts to specification in a crisscross pattern to avoid flange distortion
• Inspect thermostat operation and flush radiator passages before refilling the cooling circuit
• Run the engine to operating temperature and check for weeps at the pump-to-block joint
• Confirm belt tension and alignment to prevent premature bearing wear on the new pump shaft

What We Need From Your Inquiry

Provide your engine model—D722 or D902—along with the engine serial number so we can confirm the correct pump variant and gasket match. If your existing pump carries a worn or superseded number, a clear photograph of the nameplate allows our team to cross-reference against 1E051-73036 and 1E051-73510. For shops planning a full cooling system overhaul, list the additional components you need quoted together so we can consolidate into a single shipment.

Frequently Asked Questions

Q: What other cooling system parts should I inspect when changing this water pump? A: Check the thermostat for correct opening temperature, inspect radiator hoses for internal collapse, and flush the radiator to remove scale buildup. A stuck thermostat or blocked radiator will cause overheating even with a new pump installed. We can supply matched thermostats and seal kits alongside the pump for a complete cooling circuit service.

Q: How do I know if my engine needs 1E051-73036 or 1E051-73510? A: The correct number depends on your D722 or D902 engine serial range and block casting variant. Provide your engine serial number or a photograph of the existing pump nameplate, and our technical team will cross-reference to confirm which part number fits your specific engine build.

Q: Is the gasket included, and is it the correct material for the D722/D902 block surface? A: Yes, gasket 16871-73430 is included with the pump. It is manufactured from a heat-resistant compound designed for the thermal cycling conditions at the pump-to-block mating surface on D722 and D902 engines, avoiding the premature weep associated with generic gasket material.

Q: What causes repeated water pump failure on these Kubota engines? A: Common root causes include blocked radiator passages, degraded coolant that accelerates seal wear, a failing thermostat that allows sustained overheating, and incorrect belt tension that loads the pump bearing laterally. Replacing the pump without diagnosing these system-level issues leads to early repeat failure.

Q: Can I get a complete cooling system overhaul kit for these engines? A: We supply water pumps, thermostats, seal kits, gaskets, and related cooling components under one account. Provide your engine model and serial number along with your rebuild scope, and we will consolidate everything into a single matched kit with one warranty and one dispatch.