Please check notes in each part listing to ensure the Crankshaft Main Bearing is correct for your 1977 MERCURY MONARCH with a 4.1L 250 1BBL engine. CLEVITE/PERFECT CIRCLE & SEALED POWER are competing brands, and each brand's Crankshaft Main Bearing may be interchangeable. Special restrictions like "California only" or "with sport package" may indicate a Crankshaft Main Bearing fits only certain 1977 MERCURY MONARCH models.

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After choosing a Crankshaft Main Bearing, click the "Add Part" button. Shipping costs will be shown on the Shopping Cart page. You may use your browser's Back button, or click on "Find More Parts", to find more Engine parts, other MERCURY MONARCH parts, or parts for a different vehicle. Please try our Interactive Catalog (click red Start button above) for faster searching. Both catalogs use the same shopping cart, so any auto parts you've already chosen for your 1977 MERCURY will not be lost if you switch.