160°F 71°C Thermostat for Kubota D902 D1105 – Verified Fitment

Verified Cross-Reference — Eight superseded Kubota numbers mapped to 15321-73010, sample fitment available before bulk commitment.

Technical Specifications

Application Suitability

Why the Same Thermostat Number Ships Under Eight Different References

Kubota superseded this thermostat part number multiple times across D-series production runs.

When you pull a worn thermostat from a D1105 and read 19434-73013 on the flange, ordering that exact number from an old service manual might return a part that no longer seats correctly in a later-production housing. I have seen repair shops wait weeks for a back-ordered number only to discover the gasket surface profile changed between production years. The Thermostat 15321-73010 for Kubota D902 D1105 cross reference fitment covers the full supersession chain so buyers holding any of these eight numbers can confirm whether this unit matches their engine serial range [NEED_CITE: Kubota D-series engine thermostat supersession documentation].

Fourteen Engine Models Under One Reference

This thermostat covers the full Kubota D-series range from the three-cylinder D902 through the D1703, plus the DH1101 industrial variant. The direct-injection models D1302-DI and D1402-DI share the same 71°C opening specification but may use a different housing casting, so confirming the engine serial number against the cross-reference list eliminates trial-and-error fitment. Fleet operators running mixed Kubota-powered equipment — excavators, skid-steers, and generators — can standardize on a single Thermostat 15321-73010 for Kubota D902 D1105 cross reference fitment across multiple machine types.

What the Flange and Sealing Surface Must Match

Beyond the part number itself, physical fitment depends on the housing bore diameter, flange thickness, and sealing surface finish. A thermostat that opens at the correct temperature but sits proud of the housing face will bypass coolant and cause the slow warm-up that operators often misdiagnose as a sensor fault [NEED_CITE: thermostat bypass symptoms in small diesel engines]. We verify the flange dimensions and sealing surface machining against D1105 and D902 housings before dispatch, and we recommend requesting a sample unit for physical trial if you are replacing a superseded number you have not ordered before.

Reading the 71°C Opening Point in Real Operating Conditions

The 71°C (160°F) opening temperature matches Kubota's factory specification for D-series engines operating under construction and agricultural load. A thermostat that opens too early keeps the engine below optimal combustion temperature, increasing fuel consumption and cylinder bore glazing over hundreds of operating hours. One that opens late pushes coolant temperature toward the relief threshold of the radiator cap, accelerating hose and seal degradation. This unit's wax element is calibrated to begin opening at 71°C, maintaining the thermal window the engine was designed around [NEED_CITE: diesel engine operating temperature effects on combustion efficiency].

When a Forced Fit Costs More Than a Sample

Ordering a thermostat by an outdated number without verification sometimes results in a unit that physically enters the housing but leaves a gap at the sealing flange. The machine runs, but coolant bypasses the thermostat entirely, and the operator logs repeated overheat alarms over the following days before the root cause is found. The return freight, the second downtime window, and the diagnostic hours spent chasing sensor faults all accumulate from a single unverified part number. A sample fitment check eliminates this sequence entirely.

What Makes Sourcing Here Different

Self-produced and qualified-sourced lines carry the same QC protocol and warranty terms, so you order from one account regardless of which facility made the part. Cross-reference verification covers all eight superseded and alternate numbers for this thermostat, not just the current designation. Sample units ship for physical fitment confirmation before you commit to bulk inventory for your repair shop. The technical team confirms engine serial compatibility and housing variant identification from a machine model, a nameplate photograph, or an image of the worn part. Guangzhou warehouse stock enables fast dispatch on this and other common Kubota D-series cooling components [NEED_CITE: aftermarket parts cross-reference verification methods].

Documentation & Verification

• Commercial invoice and packing list itemized by thermostat reference number and engine application
• Cross-reference sheet mapping all eight Kubota numbers to this unit, marked reference only
• Dimensional inspection record covering flange diameter and sealing surface profile
• Warranty terms covering manufacturing defects for 3 to 12 months from delivery
• Packing photographs showing thermostat units secured against transit damage
• HS code and export customs documentation prepared for international shipment

Fitment Check Before Installation

• Compare flange outer diameter and thickness against the removed thermostat before pressing into housing
• Verify the 71°C marking on the wax element housing matches your engine service manual specification
• Check thermostat housing mating surface for scoring or corrosion that would compromise the new seal
• Dry-fit the unit into the housing bore to confirm it seats flush without lateral play
• If the flange sits proud or loose, stop installation and request a variant check against your engine serial

Tell Us What You Have

Send the engine model and serial number, or a photograph of the worn thermostat and its housing. If the nameplate is unreadable, a photo of the machine data plate or the engine block casting number is enough to run the cross-reference. For bulk orders, request a sample unit first to confirm fitment in your specific D-series variant before committing the full quantity.

Frequently Asked Questions

Q: How do I confirm this thermostat fits my specific Kubota engine serial number? A: Provide your engine model and serial number, and we cross-check against all eight reference numbers in the supersession chain. Serial ranges within the same D-series designation can span different thermostat housing configurations, so the serial number narrows the match to the correct variant. A sample unit can ship for physical trial if your engine falls near a production changeover point.

Q: My old part number is 19434-73010 — is 15321-73010 the correct replacement? A: Yes, 19434-73010 is one of the superseded numbers in the cross-reference chain for this thermostat. Kubota revised this part number several times across D-series production runs. We verify that the flange dimensions and opening temperature match your specific engine serial range before confirming the interchange, rather than assuming all numbers in the chain are drop-in equivalents.

Q: Why are there so many different part numbers for what looks like the same thermostat? A: Kubota updated the part number as housing castings, gasket materials, and production suppliers changed over the D-series lifespan. Each number in the chain — from 15321-73010 through 19434-73014 and the 1E401-73010 variant — corresponds to a specific production period or engine sub-variant. We track the full chain so you do not have to order blind from an outdated manual.

Q: I only have the machine model, not the engine number — can you still identify the right part? A: Yes, in most cases. Send us the machine model and any visible data from the equipment nameplate. We cross-reference the machine model to the likely engine series and narrow down the thermostat variant. If the machine model maps to more than one possible engine build, we will ask for a photo of the engine block or the existing thermostat to finalize the identification.

Q: Can I order a sample to check fitment before buying for my whole fleet? A: Yes. Single-piece sample orders ship from stock for physical fitment verification. Install the sample in one unit, confirm the flange seats correctly and the opening behavior matches expectations, then release the bulk order with confidence. This approach is standard practice for fleet operators standardizing thermostat supply across mixed Kubota-powered equipment.