The Ultimate Guide to Engine Main Bearing Replacement

The Ultimate Guide to Engine Main Bearing Replacement

Engine main bearings are essential components that support the crankshaft and reduce friction between the crankshaft and engine block. Over time, these bearings may wear out or become damaged, leading to engine problems. In this guide, we’ll discuss the steps involved in replacing engine main bearings, helping you to keep your engine running smoothly.

Removing the Old Bearings

The first step in engine main bearing replacement is removing the old bearings. This involves removing the oil pan, which grants access to the bearings. After this, the connecting rod caps need to be removed, allowing the crankshaft to be removed from the engine block. With the crankshaft out, the old bearings can be removed using a bearing puller. In some cases, the bearings may be stuck in place, in which case a bearing scraper will be used to remove them.

2 Bearing 2

Installing the New Bearings

Once the old bearings have been removed, the new bearings can be installed. The first step is to clean the bearing housing to remove any dirt or debris that may be present. After this, the bearings can be installed onto the crankshaft, making sure they are properly aligned. The crankshaft can then be reinstalled back into the engine block, and the connecting rod caps tightened to the manufacturer’s specifications. Finally, the oil pan can be reinstalled, and fresh oil added to the engine.

Tips for Engine Main Bearing Replacement

Replacing engine main bearings can be a challenging task, so here are a few tips to help you along the way. Firstly, make sure you have the correct tools for the job, including a bearing puller and scraper. Secondly, ensure that the new bearings are clean and free from any debris before installing them. Finally, always follow the manufacturer’s specifications when tightening the connecting rod caps, as incorrect torque settings can lead to engine problems.


Replacing engine main bearings is a complex task, but it’s essential for keeping your engine running smoothly. By following the steps outlined in this guide, you can replace your engine main bearings with confidence, knowing that you’re doing the job right. Remember to take your time, and don’t rush the process, and you’ll have a healthy engine in no time.



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