KOMATSU 6217-21-1240 Main Bearing Cap
Product Overview
The KOMATSU 6217-21-1240 Main Bearing Cap is a Genuine Komatsu OEM engine main bearing cap designed to secure the crankshaft main bearings to the cylinder block. Komatsu officially identifies this component as a Cap, and parts catalog references specify it as the Main Bearing Cap for positions No. 1 through No. 6 on compatible engines. It is a critical structural component that maintains precise crankshaft alignment, supports the main bearing shells, and ensures proper engine lubrication and durability under heavy operating loads.
Manufactured to Komatsu’s stringent OEM standards, the 6217-21-1240 Main Bearing Cap is engineered to withstand high combustion forces, crankshaft loading, and continuous engine operation in construction, mining, quarrying, and heavy-duty earthmoving applications. Designed as a direct OEM replacement, it restores the original structural integrity of the engine bottom end.
Key Features
- Genuine Komatsu OEM Main Bearing Cap
- Part Number: 6217-21-1240
- Main bearing cap for crankshaft support
- Used for Main Bearing Positions No. 1–6
- Secures main bearing shells within the cylinder block
- Maintains accurate crankshaft alignment
- Manufactured to Komatsu OEM specifications
- Direct OEM replacement
- Designed for heavy-duty diesel engine applications
- Provides long-term structural strength and reliability
Technical Specifications
| Specification | Details |
|---|---|
| Part Number | 6217-21-1240 |
| Product Type | Main Bearing Cap |
| Application | Engine Cylinder Block |
| Position | Main Bearing Caps No. 1–6 |
| Function | Secures crankshaft main bearings to the cylinder block |
| Approximate Weight | 3.99 kg |
| Installation | Direct OEM replacement |
| Brand | Komatsu |
Note: Komatsu has not publicly released detailed OEM specifications such as material grade, machining tolerances, bolt torque values, or bearing bore dimensions for the 6217-21-1240 Main Bearing Cap. The listed weight is based on parts catalog information.
Application Information
The KOMATSU 6217-21-1240 Main Bearing Cap is an essential component of the engine cylinder block assembly. Installed over the crankshaft main bearing journals, it clamps the bearing shells securely within the block, ensuring accurate crankshaft positioning and maintaining proper bearing oil clearance. Correct installation and torque are critical to engine durability, oil pressure stability, and long-term crankshaft performance.
Manufactured to Komatsu OEM standards, the main bearing cap is designed to withstand:
- High combustion and crankshaft loads
- Continuous engine vibration
- Heavy-duty diesel engine operation
- Thermal expansion and contraction
- Long operating hours
- Severe mining, construction, and quarry environments
Compatible Komatsu Equipment
The KOMATSU 6217-21-1240 Main Bearing Cap is used on Komatsu machines equipped with compatible SAA6D140E-series diesel engines, including:
Crawler Dozers
- D155A-6R
- D155AX-6
- D155AX-8
- D155AXi-8
- D275AX-5
- D375A series (selected models equipped with compatible SAA6D140E engines)
Articulated Dump Trucks
- HM350-1L
Compatibility depends on the engine model, serial number, and cylinder block configuration. Always verify compatibility using the machine’s Product Identification Number (PIN), Machine Serial Number, Engine Serial Number, and existing part number before ordering.
Additional Compatibility Information
The 6217-21-1240 Main Bearing Cap is a configuration-specific engine component. Before installation, verify:
- Machine model
- Machine Serial Number
- Product Identification Number (PIN)
- Engine model and serial number
- Cylinder block configuration
- Main bearing cap position (No. 1–6)
- Existing part number
Since main bearing caps are precision-machined with the engine block, they should only be replaced following Komatsu service procedures to ensure correct bearing clearances and crankshaft alignment.
Benefits
Installing a genuine KOMATSU 6217-21-1240 Main Bearing Cap helps:
- Restore proper crankshaft support and alignment
- Maintain correct main bearing retention
- Ensure stable engine oil clearance
- Improve engine reliability and durability
- Reduce premature wear of crankshaft and bearings
- Minimize engine-related downtime
- Preserve original OEM engine performance
- Deliver OEM-quality fit, strength, and long-lasting performance in demanding heavy-duty applications.
- Brand New / Genuine Surplus Komatsu Part
- Professionally inspected before dispatch
- Ready for immediate shipment (subject to stock availability)
Worldwide Shipping
We maintain ready-to-ship inventory for many Caterpillar parts. Orders are dispatched the same business day upon receipt of bank payment, with fast worldwide delivery available via DHL and FedEx.
Disclaimer: We are an independent supplier of genuine surplus Komatsu parts. We are not an authorized Komatsu distributor or dealer. All trademarks, product names, and model numbers are used solely for identification purposes.
