Motor housing and problems with its rotation. How to determine that the problem is in it?

It is very rare for a manufacturing defect to cause the bearing shell to rotate in the motor. Most often this is due to negligence in work. The engine housing is designed for the huge overloads caused by the operation of the connecting rod and piston. However, due to heavy use, it may curl. What to do in this case? How much does an engine crankcase replacement cost? All this (and much more) you will learn by reading our article!

Engine bearing shell - what is it?

This is one of the parts of plain bearings. The connecting rod insert is present on its shank and head. Its shape resembles a crescent. It has a flat surface, which must be in contact with the attachment point on the connecting rod. The surface of these components has grooves to ensure movement and precise distribution of engine oil. Crankshaft liners fit on each side of the socket connecting rodwhich is mounted on the shaft.

Rotation of the acetabulum - why does this happen?

The engine shell is responsible for mitigating friction between the elements of the piston-crank system. However, it needs engine oil to work effectively. What is the main reason for the failure of the bearing and the twisting of this element? This is primarily a neglect of the oil interval. Lack of oil is a recipe for gripping and rotating the acetabulum. If a problem occurs, the driver can recognize the symptoms without removing the underside of the engine.

Turned cup - symptoms 

Worn bushings, twisted due to friction, begin to knock very distinctly when the piston is working. This can be compared to hitting a metal hammer on another metal object. The sound cannot be confused with any other. Most often, you will hear damaged bushings at high engine speeds, but in many cases you will notice a distinct knock from the moment you start the drive.

Damaged bearing shell - the consequences of driving with a breakdown

After diagnosing a problem with the engine housing, you should not go further. Why? The lack of lubrication on the shaft journal and the rotation of the bearing shell cause wear on the crankshaft surface in a sensitive area. A damaged engine case can also be further destroyed by work and release metal filings into the lubricant. If sawdust gets into other engine components, it will scratch the surface or clog oil passages.

How to diagnose damaged crankshaft bearings?

The least invasive ways to diagnose shaft bearings are:

• turning off the ignition coils when the unit is running;
• rotation of the shaft and touching the surface of the piston with a hard (non-scratching) element.

The first method is the least time consuming and you don't have to parse many elements. If you suspect that the engine case has turned over, start the machine and disconnect the coils from one cylinder at a time. Remember to do it carefully. Of course, a sparkless motor will fail on this cylinder, but once you find the right one, the bearing knock will noticeably subside.

How else to check if the problem is in the motor housing?

You can try the following method on diesel engines where the previous method would not work. Rotated cups give the symptoms of tapping, but also increase the space between the foot and the broken piece. How to check? You need to take a long and hard object (like a screwdriver) and turn the shaft until the piston is out of TDC. Then press the screwdriver firmly against the top of the piston. If you hear and feel a distinct click, then the engine shell in this connecting rod has failed.

Replacing a bearing in an engine - costs

To get rid of the malfunction, you will have to carry out a major overhaul or preventive replacement of the engine. You need to disassemble the lower part of the block and get rid of the engine crankshaft journal, bearings and a specific connecting rod. A turned socket requires not only replacing the kit with a new one, but also inspecting other contact elements. In the vast majority of cases, the crankshaft and connecting rod must be reground by a mechanic. This is an optimistic version, because in extreme cases the engine block can fail. A defective motor cover will result in repair or replacement of the drive.

Engine housing - how to avoid damage

Remember that this type of failure is rarely due to a manufacturing defect. The exception is the 1.9 dCi unit from Renault. The bearing farthest from the oil pump was stuck in it due to lack of lubrication. To avoid such damage, change the oil regularly at appropriate intervals and use only the recommended oils for your engine.

The engine housing is a small element, but extremely important for the proper operation of the power unit. In order not to incur significant costs for replacing the entire engine, take care of regular oil changes, and in case of alarming symptoms, do not underestimate knocking.