Water Pump 1E051-73036 for Kubota D722 D902 – Direct Fit

Cross-reference verified — Each Water Pump 1E051-73036 is matched against Kubota D722 and D902 block face dimensions and port orientation before dispatch, eliminating blind swaps based on copied tables.

Technical Specifications

Application Suitability

Why the Same Base Number Arrives in Multiple Variants and How to Confirm Fit

A verified cross-reference check against machine serial prefix resolves the ambiguity before the part ships.

Superseded part numbers, casting revisions across production years, and copied cross-reference tables with uncorrected errors turn a routine coolant pump replacement into a fitment uncertainty. A pump carrying the same base identifier may have a different coolant port angle, an altered mounting bolt circle, or a gasket surface machined to a different flatness specification depending on the engine build it left the factory with. I have seen machines sit idle in the field because the replacement bolted up physically but the inlet port faced the wrong direction by a few degrees — enough to kink the hose and cause a restricted-flow overheat within operating hours [NEED_CITE: coolant system flow restriction diagnostics for compact diesel engines]. The Water Pump 1E051-73036 for Kubota D722 D902 cross reference fitment requires matching the engine serial prefix, not just the machine badge.

Matching Engine Serial Prefix to Pump Variant

The Kubota D722 and D902 share a common block architecture but differ in bore, stroke, and coolant passage routing. This Water Pump 1E051-73036 is dimensionally verified against both engine families, yet the specific variant shipped depends on the engine serial prefix recorded on the nameplate. Providing the full machine model — whether BX1880-1, RTV-X900G, or ZD1021-3 — allows the technical team to narrow the correct pump configuration and confirm that the coolant outlet angle, mounting hole spacing, and impeller depth all match the block face in question.

Port Orientation and Gasket Surface Verification

The coolant inlet and outlet port positions on this pump are checked against the mating block face for each confirmed engine variant. A port clocked even slightly off from the original casting will force the hose into a bend radius that restricts flow or accelerates hose fatigue. The included MLS gasket — part number 16871-73430 (cross-reference only) — uses a multi-layer steel construction with elastomeric coating designed to accommodate the thermal expansion differential between the cast-iron block and the aluminum pump housing. The ±0.05 mm dimensional tolerance on the gasket mating surface ensures uniform clamping without the need for supplementary sealant [NEED_CITE: MLS gasket sealing principles for dissimilar metal joints in small diesel engines].

Interpreting Core Specifications for Field Reliability

The T6 heat-treated aluminum alloy housing provides dimensional stability under the thermal cycling typical of compact diesel cooling systems, where coolant temperature swings between cold-start ambient and sustained operating levels within minutes. The dual-lip NBR shaft seal, rated for 120°C continuous operation, addresses the common failure mode of single-lip seals that harden and leak after repeated heat exposure. The impeller is balanced to ISO 1940 G6.3, which limits vibration transfer to the front cover bearings and reduces the likelihood of premature bearing wear that manifests as shaft wobble and seal weeping. The 1.2 bar pressure hold test at the factory confirms housing integrity and gasket surface flatness before the unit leaves the inspection bench.

The Hidden Cost of Skipping the Variant Check

Ordering a pump by base number alone, without confirming the machine serial prefix and port orientation, risks a unit that physically mounts but misaligns the coolant passages. The result is either a return shipment with associated freight cost and lead time, or worse — installation proceeds with a marginal fit that causes a slow leak or restricted flow, leading to an overheat event days or weeks later. In a mining or contracting environment where the machine is revenue-generating, the downtime from a second teardown far outweighs the time spent confirming fitment data upfront [NEED_CITE: cost impact of repeat teardowns on compact equipment in field service].

Why Procurement Through This Channel Works

Selected part lines are produced in-house while the remainder is sourced from qualified ISO-certified manufacturing partners, meaning both streams carry the same quality control standards and warranty terms — this pump ships under a unified six-month manufacturing defect warranty regardless of origin. The eight-category product coverage means that if the repair also calls for thermostat seals, coolant hoses, or radiator caps, those items can ship in the same consignment under one account. A single-piece minimum order removes the barrier for an emergency replacement or a sample unit. The Guangzhou warehouse stocks common-fitment items for fast dispatch, and the technical team is available to cross-check machine model, serial prefix, and worn nameplate photographs to confirm the correct variant before commitment.

Documentation & Verification

• Commercial invoice and packing list referencing machine model and confirmed engine serial prefix
• Part compatibility and cross-reference sheet marking all OEM numbers as reference only
• Dimensional inspection record covering port spacing, bolt circle, and gasket surface flatness
• Warranty terms covering manufacturing defects for six months from dispatch
• Packing photographs showing anti-vibration foam placement and branded carton condition
• HS code classification and customs documentation support for international shipment

Fitment Check Before Installation

• Compare bolt circle diameter and hole count against the removed pump before removing protective packaging
• Verify coolant port clock position matches the original casting using a straightedge reference
• Confirm MLS gasket sits flush on the pump mating face without rocking or overhang
• Dry-fit the pump to the block without sealant to check flange contact uniformity before final torque
• If port orientation or bolt pattern does not match, halt installation and contact technical support with photographs

Confirm Your Exact Fit Before Ordering

Provide the full machine model, engine serial prefix, or a clear photograph of the existing pump and nameplate. The technical team will cross-reference the variant, confirm port orientation and gasket match, and advise on sample availability for physical trial before you commit to fleet quantity.

Frequently Asked Questions

Q: How do I confirm this pump fits my exact Kubota model variant? A: Share the complete machine model — such as BX1880-1 or ZD1021-3 — along with the engine serial prefix from the nameplate. The technical team cross-checks this against the verified fitment list, confirming port orientation, bolt pattern, and gasket type match your specific engine build before any unit ships.

Q: The old part number on my pump is different — is 1E051-73036 still correct? A: Kubota has superseded certain coolant pump numbers across production generations. Provide the old number along with your machine model and the team will trace the replacement path, confirming whether 1E051-73036 is the current valid cross-reference for your engine serial range.

Q: Why does the same base number appear with different gasket types? A: Earlier production runs used fiber-composite gaskets while later builds shifted to MLS construction to handle the expansion differential between aluminum housings and cast-iron blocks. The gasket supplied with this pump — 16871-73430 — is the MLS type matched to current engine build specifications.

Q: I only have the machine model, no readable part number — can you identify the correct pump? A: Yes. Provide the machine model and, if possible, a photograph of the nameplate or the engine serial stamping. The team uses this data to narrow the correct pump variant and confirm fitment, eliminating the need for a physical part number.

Q: Can I get one sample to test fit before ordering for the fleet? A: A single sample unit is available for physical fitment trial. This allows your workshop to verify bolt pattern, port alignment, and gasket seating on one machine before committing to a fleet-quantity order.