Miller Diesel Cold Weather Kit for Bobcat 250 & Trailblazer 325

Technical Winterization for Diesel Welders

The Miller 301115 Cold Weather Kit is a field-installable accessory designed to optimize the operational envelope of Bobcat™ 250 Diesel and Trailblazer® 325 Diesel engine-driven welders. In industrial environments where equipment is exposed to sub-zero temperatures, standard glow plugs may not be sufficient to ensure reliable ignition or continuous operation. This kit provides a dual-stage thermal solution targeting the two most critical failure points in cold diesel operation: the engine block thermal mass and the fuel delivery system.

Component Breakdown

1. Engine Block Heater: This component is installed directly into the engine's coolant system or block. By utilizing an external power source (typically 120V AC), the heating element maintains the engine block at a temperature significantly above ambient. This reduces the viscosity of the engine oil, allowing for rapid lubrication of bearings and pistons during the cranking phase, and reduces the compression resistance the starter motor must overcome. This results in faster cranking speeds and immediate combustion.

2. Fuel Heater Assembly: Diesel fuel contains paraffin wax which can crystallize (gel) at low temperatures, leading to the "Cloud Point" and eventually the "Pour Point" where fuel ceases to flow. The fuel heater included in this kit is positioned to warm the fuel before it passes through the filter media. This prevents wax crystals from blinding the filter, ensuring consistent fuel pressure and preventing engine starvation or stalling under load.

Installation and Compatibility

This kit is engineered strictly for the diesel variants of the Bobcat 250 and Trailblazer 325. It is not compatible with gasoline models or older non-diesel iterations. Installation involves mounting the heating elements and routing the necessary wiring harnesses within the machine's enclosure. As an OEM part, it adheres to Miller's rigorous safety standards, ensuring that the addition of heating elements does not compromise the machine's IP rating or electrical safety. For MRO professionals and fleet managers, equipping your diesel fleet with the 301115 kit is a proactive maintenance strategy that minimizes winter downtime and service calls.