Mitsubishi Engine Piston Ring Set S3L S3L2 S4L S4L2 K3F K4F MM437295 MM433921 31A17-00010

Product Details

Product Overview

This high-quality piston ring set is specifically engineered for a range of Mitsubishi industrial diesel engines, including the popular S3L, S3L2, S4L, S4L2, K3F, and K4F models. Designed to restore compression, reduce oil consumption, and optimize engine performance, this kit is an essential component for engine overhaul and maintenance.

The set includes the exact cross-reference parts MM437295, MM433921, and 31A17-00010, ensuring compatibility with your specific engine configuration. Manufactured under strict quality controls, these rings are suitable for a wide variety of heavy-duty applications, from construction machinery and agricultural tractors to marine gensets and material handling equipment.

Key Features & Benefits

• Precision Fitment: Produced to OEM size specifications, ensuring a perfect seal within the cylinder bore for maximum compression and power output.
• Durable Material: Constructed from high-grade cast iron and steel alloys, providing excellent wear resistance and long service life under high-temperature, high-pressure diesel conditions.
• Oil Control Optimization: Specifically designed ring profiles (compression, intermediate, and oil rings) work together to minimize oil consumption and prevent blow-by.
• Comprehensive Kit: Includes all necessary rings for a single cylinder, simplifying the ordering process and ensuring you have the correct components for a complete rebuild.
• Rigorous Testing: Each batch undergoes machinery test reports and outgoing video inspections to guarantee dimensional accuracy and material integrity.
• Versatile Application: Ideal for use in excavators, generators, agricultural pumps, and other diesel-powered equipment relying on Mitsubishi S and K series engines.

Technical Specifications

OEM Cross-Reference

This piston ring set directly replaces the following OEM and manufacturer part numbers, providing a reliable alternative to genuine Mitsubishi parts while maintaining functional equivalence:

• Mitsubishi: MM437295, MM433921, 31A17-00010
• Associated Numbers: These numbers are commonly found on genuine Mitsubishi service parts for the S and K series engine families. Always verify your existing part number against this list before ordering.

Compatibility

This piston ring set is commonly used for the following Mitsubishi engine models and their associated equipment:

• Engine Models: S3L, S3L2, S4L, S4L2, K3F, K4F
• Applications: These engines are widely installed in excavators, mini excavators, agricultural tractors, forklifts, generator sets (gensets), marine auxiliary engines, and industrial pumps from brands like Caterpillar (in smaller models), John Deere, and various Chinese machinery manufacturers that utilize Mitsubishi power plants.

Global Supply & Distribution

We offer reliable worldwide shipping to meet the demands of international B2B buyers. Our logistics network ensures fast and secure delivery to major ports and industrial centers across all continents.

• Major Markets Served: North America (USA, Canada, Mexico), Europe (Germany, UK, Netherlands, France), Asia-Pacific (Australia, Japan, Korea, Southeast Asia), Middle East (UAE, Saudi Arabia), Africa, and South America.
• Shipping Options: Express delivery (DHL, FedEx, UPS) for urgent orders, air freight for medium-volume shipments, and sea freight (FCL/LCL) for bulk orders to reduce per-unit costs.
• Trade Compliance: Our team has extensive experience in export documentation and customs clearance, ensuring smooth transactions for international buyers.

Quality Assurance

We stand behind the quality and reliability of our parts. Every set is manufactured in an ISO-certified facility with a focus on precision engineering.

• Manufacturing Standards: Components are produced using advanced casting and machining processes to meet or exceed OEM performance criteria.
• Testing: A Machinery Test Report is available upon request, verifying the mechanical properties of the rings. Video Outgoing Inspection is provided to confirm packaging and part appearance before shipment.
• Warranty: Each set is backed by a 6-month warranty against manufacturing defects in materials and workmanship.

FAQ

Q1: How do I confirm this piston ring set fits my specific engine?
A: Verify your engine model number (e.g., S4L or K4F) stamped on the engine block. Additionally, check your old piston ring packaging or service manual for the OEM part numbers (MM437295, MM433921, or 31A17-00010). If these match, the set is compatible.

Q2: What is the recommended installation procedure for these rings?
A: Installation should be performed by a qualified diesel mechanic. Ensure the cylinder bore is within service limits and properly honed. Install the rings using a ring expander to avoid breakage. Stagger the ring gaps (typically 120 degrees apart) to prevent gas blow-by. Always lubricate the rings with clean engine oil during assembly.

Q3: Can I use these rings if my cylinder bore has been oversized?
A: No. This specific set is produced to “OEM Size,” which corresponds to the standard factory bore diameter. If your cylinder has been bored oversize (e.g., 0.25mm, 0.50mm), you must purchase a piston ring set specifically designed for that oversize dimension to maintain proper clearance and sealing.