The connecting rod takes the force, which the piston receives, and transfers it to the crankshaft. Since it is constantly affected by compressing and pulling force, it needs to be sufficiently strong and rigid. There is an oil jet attached to the big end of the connecting rod for lubrication and cooling. Engine oil is supplied through the crankshaft engine oil hole. The connecting rod attaches to the bearing cap, so check the front mark as not to make a mistake when assembling the two parts.