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Check of radical bearings and bearings of rods

Causes of wear of bearings

1. Decrease in strength of metal; scratches torn 2. incorrectly planted; bright (polished) strips 3. scratched with dirt; the dirt has eaten into the surface of the bearing 4. The lack of oil; top layer was wiped 5. Excessive wear; the upper layer was wiped across the surface 6. The bearing is deformed; the top layer was wiped on a circle

Despite the fact that the main and connecting rod bearings at engine major repairs must be replaced, the old bearings should be stored at the place of installation for a thorough check, as traces of wear on these details allow you to restore the general condition of the engine.

The reasons for the destruction of the crankshaft bearings are poor lubrication, the presence of dirt and foreign particles, motor overload and corrosion.

Whatever the reason, caused destruction of bearings, it should be removed before final assembly of the motor, to avoid repeated damage these parts.

Dirt and debris fall into the engine for various reasons - in the assembly process, through filters or crankcase ventilation system, through the oil.

Often, contamination from metal particles are present machining engine parts, or due to wear during normal operation of the engine. Sometimes at pollution there remains of abrasive materials after the lapping and grinding works, especially at insufficient washing and Cleaning. Regardless of the cause of origin of foreign contamination is usually introduced into a soft alloy of the bearing and are easily distinguishable.

Large particles can not penetrate into the bearing and lead to scratching and scuffing on the surfaces of both the bearing and the crankshaft journals.

The best way to eliminate the causes of this deterioration is careful washing of parts and maintaining impeccable cleanliness during engine assembly. In order to prevent premature wear and recommend more frequent oil changes and filters.

Insufficient lubrication of the engine can be caused by a number of interrelated reasons. These include excessive engine overheating (causing oil dilution), overload (cause squeezing oil from the surface of bearings) and pressure drop due to leakage (emission) of oil (due to increased clearance in the bearings, wear of the oil pump, high engine speed ). The reason for the accelerated wear of the bearings of the crankshaft and is blocking of oil channels, usually due to misalignment lubrication holes in the bearing and the details of his body, which causes insufficient lubrication and failure. When the cause of failure is a lack of lubrication, there is a wipe or extrusion coating material bearing with a steel base. The temperature rises to such a level that overheating occurs chipping steel base bearing blue, there is a possibility of deformation bearing cap bolts and rods.

The durability of the crankshaft bearings also depends significantly on the driving skills and character movement. Bearings are experiencing increased stress when driving at full throttle, prolonged driving at low speeds, when slippage. At high loads occur squeezing the oil film bearings are experiencing bending deformation, in which microcracks (fatigue wear). Typically, the coating is detached from the bearing steel substrate in the form of fine particles. Travel a short distance can cause corrosive wear of bearings as because of insufficient warming do not have time to leave the condensed moisture and gases, corrosive. These components are accumulated in the oil, causing the formation of acid and insoluble precipitates. As the oil flow to the bearings is their corrosion by acids, causing their destruction and failure.

Bearing failures may also be caused by improper installation during assembly of the engine. Too tight fit is the cause of insufficient lubricant backlash and poor penetration of grease. Dirt and debris trapped under the rear side of the bearing, causing uneven it fit and premature failure.