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281670 - Miller Replacement Kubota D722 Diesel Engine Assembly

Packaging: 1 per ea
$20,668.36/ea $14,505.31/1 per ea only $14,505.31/eaSave 30%

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OVERVIEW

Get Your Welder Running Like New with the Miller 281670 Engine

When the heart of your diesel welder stops beating, your entire operation grinds to a halt. The Miller 281670 is the genuine replacement Kubota D722 diesel engine designed to get your Miller Bobcat or Trailblazer back in the field where it belongs. We know that in the welding business, downtime equals lost revenue. That is why we offer this direct-replacement engine assembly, allowing you to swap out a tired or seized motor with a brand-new, factory-spec unit without the headaches of trying to retrofit a generic engine.

The Kubota D722 is legendary for a reason. It is a workhorse that sips fuel while providing the steady, high-torque output needed to maintain a stable arc, whether you are gouging, running heavy flux-cored wire, or stick welding on a pipeline. This 3-cylinder diesel is built to handle the rough conditions of job sites, from freezing cold mornings to scorching summer afternoons. Its liquid-cooled design prevents overheating during long duty cycles, ensuring your machine doesn't quit before you do. Plus, the electric start system means reliable ignition every time you turn the key.

Replacing your engine with this genuine Miller part protects your investment. Because it is the exact engine specified by Miller engineers, you don't have to worry about misalignment causing vibration issues that could damage your generator head or electronics. It drops right in, bolts up, and connects to your existing fuel and electrical systems. Don't gamble with aftermarket knock-offs that might void your machine's remaining warranty or fail prematurely. Stick with the OEM quality of the Miller 281670 Kubota D722 and keep your arcs burning bright for years to come.

Why Choose the OEM Replacement?

  • Perfect Fit: No drilling, cutting, or welding mounts required.
  • Reliable Power: Consistent RPMs mean consistent voltage and amperage.
  • Longevity: Kubota diesels are known for running thousands of hours with proper maintenance.
  • Resale Value: Keeping your machine 100% Miller/Kubota maintains its value.
Additional Information
Brand:Miller
Packaging Description:1-per-ea
Engine Model:Kubota D722
Fuel Type:Diesel
Cylinders:3
Cooling System:Liquid Cooled
Part Type:Replacement Engine Assembly

INCLUDED

  • 1 x Complete Kubota D722 Diesel Engine Assembly
  • Installation Hardware (pre-mounted)
  • Owner's Manual / Documentation

APPLICATIONS

  • Replacement engine for Miller Bobcat 250 Diesel Welders
  • Replacement engine for Miller Trailblazer 302 Diesel Welders
  • Heavy-duty industrial mobile welding applications
  • Construction site power generation
  • Agricultural equipment repair (where compatible)

FAQ

Yes, the Miller 281670 is a complete engine block assembly including the head and internal components. However, you may need to transfer external accessories like the muffler, radiator, or specific alternator brackets from your old engine depending on the specific welder model.

Generally, a high-quality diesel-rated oil such as 10W-30 or 15W-40 (CJ-4 or CK-4 rated) is recommended, but always check the specific owner's manual included with the engine for temperature-specific viscosity charts.

No, replacement engines are typically shipped 'dry' to prevent leakage during transport. You must fill the crankcase with oil and the cooling system with coolant before attempting to start the engine.

This part number (281670) is used in many Miller diesel welders, including versions of the Bobcat 250. However, Miller makes changes based on serial number ranges. Please verify your welder's serial number against the parts manual to confirm this is the correct SKU.

The Kubota D722 typically produces approximately 19-20 HP at 3600 RPM, though the specific output setting is governed to match the generator head requirements of the Miller welder.

Typically, new OEM replacement engines from Miller do not have a core charge, but this can vary by distributor policy. It is a brand new unit, not a remanufactured one.

Avoid prolonged idling for the first 50 hours. Operate the engine under moderate load to seat the piston rings properly, and perform the first oil change after the initial 50-hour break-in period.

Most Miller-spec Kubota assemblies include the fuel shut-off solenoid, as it is integral to the electric start/stop system of the welder.