Toyota 13041-0P040-01 Bearing, Connecting Rod

It is necessary to save the previous main and connecting rod bearings during the engine overhaul because they tell a lot about the engine status. Main causes of bearing failure are reduced lubrication, contamination with dirt or contaminants, overloading of the engine, and corrosion, which must be eliminated before reassembly. When inspecting bearings, it is essential to pull them out from sealed area so that when matching the defects with the crankshaft journal, the bearings must be placed on a clean flat surface. Contaminants can get into the engine during the assembly process or as dirty filters are replaced, or during machining operations and become lodged in the bearing material, to the latter's detriment. To avoid this, it is advised that the parts be well cleaned and the oil and filter be changed frequently. Cases of inadequate lubrication include high temperatures, overloading, oil loss or when there is blockage in the oil channels leading to serious bearing abuse. Driving habits likewise affect bearing life; for example, low-speed operation in high gears is a fatigue failure problem, while short trips are a wear problem because of insufficient heat. Another failure mode common with bearings is that of incorrect installation that could include tight-fitting bearings or debris trapped within the bearing. When renewing bearings, it goes without saying that care must be exercized in selecting them and if, for example, the bearings are the undersize type because the crankshaft has been reground, the oil clearances are incorrect or the original bearings are worn or damaged this is particularly so. For standard size main bearings, use the bearing number corresponding to the original one, for connecting rod bearings, use the number on the surface of the connecting rod cap. Finally, oil clearance is the criteria to decide the new bearing size, but help from auto parts stores or dealers may be helpful if there are doubts.