What is the primary function of main bearings?

Main bearings support the crankshaft within the engine block. They allow the crankshaft to rotate smoothly while handling significant loads and maintaining proper oil clearance.

What does 'bi-metal aluminum' construction mean for these bearings?

This construction uses a layer of aluminum alloy bonded to a steel backing. The aluminum provides good bearing properties and conformability, while the steel backing offers strength and rigidity.

Are these bearings a direct replacement for the original equipment?

These bearings are designed as a direct replacement for the main bearings in the specified Mercedes Benz engines. Proper installation according to manufacturer specifications is recommended.

Specifications

Brand: King Engine Bearings
Part #: MB7721AM
UPC: 611500209406

King Engine Bearings Mercedes Benz M103 / M104 / OM603 Bi-Metal Aluminum Main Bearing Set

Name: King Engine Bearings Mercedes Benz M103 / M104 / OM603 Bi-Metal Aluminum Main Bearing Set
Brand: King Engine Bearings
SKU: king-engine-bearings-king-engine-bearings-mercedes-benz-m103-m104-om603-bi-metal-t14-425997
Price: 73.01 USD
Availability: BackOrder

$73.01

On Backorder

Order now to reserve yours — we'll ship as soon as stock arrives. Full refund if we're unable to fulfill.

King Engine Bearings main bearing set for Mercedes Benz M103, M104, and OM603 engines. Bi-metal aluminum construction for reliable engine performance.

Key Features

Fits Mercedes Benz M103, M104, and OM603 engines.
Bi-metal aluminum construction offers a strong and conformable bearing surface.
Designed to support the crankshaft and reduce friction.
Helps maintain consistent oil film for reduced wear.

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About this part

Product Details

If you're rebuilding the engine in your Mercedes Benz with an M103, M104, or OM603 engine, this bi-metal aluminum main bearing set from King Engine Bearings is a solid option. These bearings are crucial for supporting the crankshaft and ensuring it spins smoothly within the engine block. They handle the immense loads and high speeds generated during operation, making their condition vital for overall engine health.

King Engine Bearings uses a bi-metal aluminum construction for this set, which offers a good balance of strength and conformability. This means the bearings can adapt slightly to the crankshaft's surface while still providing strong support. This design helps to maintain consistent oil film thickness, reducing friction and wear on both the bearings and the crankshaft. Proper installation, ensuring the crankshaft journals are clean and within spec, is key to getting the most out of these bearings.