المحرك Mitsubishi S3L2 لـ حفارة صغيرة Caterpillar 302.5C 303CR 303SR

1. Engine Specifications and Performance
The S3L2 is designed for industrial and construction applications, focusing on high torque at low engine speeds to maximize hydraulic breakout force.

Type: 4-Cycle, Vertical, Water-cooled Diesel
Number of Cylinders: 3
Displacement: 1.318 Liters
Aspiration: Naturally Aspirated
Combustion System: Swirl Chamber (Indirect Injection)
Rated Output: Approximately 18.0 - 22.0 kW @ 2200-2400 RPM (Depending on specific machine tuning)

2. Caterpillar Machine Applications
While Mitsubishi produces the base engine, it is often branded as the Caterpillar C1.1 in newer iterations or maintained as the S3L2 in specific regional models.

Caterpillar 302.5C: Utilizing the S3L2 for its high hydraulic flow requirements, ensuring the machine can lift and travel simultaneously without stalling.
Caterpillar 303CR: The "Compact Radius" design requires an engine with a small footprint. The S3L2 fits perfectly within the tight counterweight swing of this model.
Caterpillar 303SR: Engineered for urban utility work where noise and emission controls are paramount.

3. Key Technical Features
Quiet Operation: The engine features a specialized crankcase and gear train design that minimizes mechanical clatter, a vital feature for machines working in residential areas.
Direct-to-Hydraulic Power: The flywheel housing is precisely machined to accept the heavy-duty tandem or triple hydraulic pumps used in Caterpillar excavators.
Easy Serviceability: All primary maintenance points—including oil filter, fuel filter, and dipstick—are located on the same side of the engine for easy access through the excavator’s rear hood.

4. Maintenance and Service Protocol
To ensure the long-term durability of the Mitsubishi S3L2 in your Caterpillar excavator, adhere to the following maintenance standards:

Engine Oil: Change every 250 to 500 hours using premium 15W-40 or 10W-30 oil. The S3L2 has a sensitive lubrication circuit; never bypass oil changes.
Cooling System: Use a high-quality 50/50 ethylene glycol mix. Ensure the radiator is blown out regularly, as mini excavators operate in high-dust environments.
Fuel System: Indirect injection systems require clean fuel to prevent injector clogging. Replace the fuel filter and clean the water separator every 500 hours.
Glow Plugs: Check glow plug resistance annually to ensure reliable starting in cold climates, as indirect injection engines rely heavily on pre-heating.

5. Why Partner With a 13-Year Engine Expert?
Sourcing parts for a Caterpillar-application Mitsubishi engine can be complex due to specific "Cat-only" external components. We offer:

Genuine Mitsubishi and Cat Parts: We provide original internal components (pistons, rings, bearings, gaskets) that match the OEM hardness and thermal expansion specs.
Complete Engine Solutions: Available in brand-new original, professional remanufactured, or "long block" configurations to suit your budget and timeline.
Technical Expertise: We can help identify if you need the "Short Nose" or "Long Nose" crankshaft variant, which is a common point of confusion when ordering S3L2 engines.
Global Logistics: Our engines are packed in export-ready, shock-proof wooden crates and shipped via express air or sea freight.

6. Ordering Information
To ensure 100% fitment for your Caterpillar 302.5C, 303CR, or 303SR, please provide:

The Engine Serial Number (found on the nameplate on the side of the block).

The Caterpillar Machine Serial Number (found on the chassis plate).

A photo of the hydraulic pump mounting side to verify the flywheel housing configuration.