What does '.50 Oversized' mean for these main bearings?

'.50 Oversized' means these bearings are thicker than standard by 0.50mm. They are intended for use when the crankshaft journals have been machined down by 0.50mm to correct wear or damage, restoring proper oil clearance.

Are these bearings compatible with both 1.6L and 1.8L M40 engines?

Yes, these ACL main bearings are specifically designed for the BMW M40 engine family, covering displacements of 1.6L, 1.8L, and 1.9L, which includes the M40B16 and M40B18 variants.

What other parts are typically needed when installing main bearings?

When installing main bearings during an engine rebuild, you'll generally need matching rod bearings, new engine oil, an oil filter, and potentially new crankshaft seals and gaskets. Always consult your vehicle's service manual for a complete list.

ACL BMW M40B16/18 (1.6L / 1.8L / 1.9L) .50 Oversized Main Bearing Set

Specifications

Brand: ACL
Part #: 5M1538H-.50
UPC: 9315726432914

ACL BMW M40B16/18 (1.6L / 1.8L / 1.9L) .50 Oversized Main Bearing Set

Name: ACL BMW M40B16/18 (1.6L / 1.8L / 1.9L) .50 Oversized Main Bearing Set
Brand: ACL
Price: 195.96 USD
Availability: InStock

$195.96

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Fits 1996-1999 BMW 318ti. ACL .50mm oversized main bearing set for M40B16/18 engines. Essential for engine rebuilds.

Key Features

Fits 1996-1999 BMW 318i, 318is, 318ti, and Z3.
Designed for M40B16, M40B18, and M40B19 engines.
Main bearings are .50mm oversized for use with machined crankshafts.
Features a tri-metal overlay for improved strength and oil retention.
Helps reduce friction and wear in the engine's rotating assembly.
Essential component for engine rebuilding and repair.

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Will this fit your vehicle?

Product Details

When you're rebuilding the engine in your 1996-1999 BMW 318ti, 318is, 318i, or Z3 with the M40B16, M40B18, or M40B19 engine, getting the main bearings right is critical. These ACL main bearings are .50mm oversized, meaning they're designed to be used when the crankshaft journals have been machined down by .50mm to clean up wear or damage. This set is built to handle the demands of a refreshed engine, ensuring proper oil clearance and support for the rotating assembly.

ACL has been making engine bearings for a long time, and they use a tri-metal overlay material that's known for its strength and ability to hold oil. This construction helps reduce friction and wear, which is especially important in a performance or rebuilt engine where clearances might be tighter or operating conditions more demanding. Installing these bearings correctly, with the proper oil clearance and lubrication, will help ensure the longevity and smooth operation of your engine.

When you're doing an engine rebuild, it's important to have all the necessary parts. Make sure you've also got the matching rod bearings and any other seals or gaskets you might need to complete the job. Always refer to your vehicle's service manual for the correct installation procedures and torque specifications.