Pistons and crankshafts form the heart of a combustion engine. These parts convert the pressure from combustion into rotational motion and are heavily stressed during every engine revolution. In this collection, you will find pistons, piston components, crankshafts, and related parts for maintenance, overhaul, and engine building.
The piston moves up and down in the cylinder and transfers the force of combustion through the connecting rod to the crankshaft. The crankshaft then converts this linear motion into the rotational motion that drives the transmission and ultimately the rear wheel.
Due to the high engine speed, these parts are continuously exposed to varying forces, heat, and friction. Proper fit and lubrication are therefore essential.
Wear on pistons, piston rings, bearings, or crankshaft journals can manifest as oil consumption, compression loss, mechanical noises, metal particles in the oil, or excessive play. Continuing to drive with damaged parts can cause serious further damage.
A reliable diagnosis requires disassembly and precise measurements. It is not possible to determine with certainty which internal part is defective based solely on noise or visible smoke.
Pistons and crankshafts must exactly match the engine type. For pistons, pay attention to bore size, compression height, piston pin, valve reliefs, and required cylinder clearance. For a crankshaft, stroke, bearing sizes, connecting rod design, and balancing are important.
Always check the engine code and technical specifications. The engine model and year alone are not always sufficient, as manufacturers may use different engine variants within a model range.
For a standard overhaul, parts that match the original dimensions and compression ratio are usually used. For a performance-oriented engine build, forged pistons, modified compression ratios, or other crankshaft configurations may be applied.
Such modifications affect the load, tuning, and heat development of the engine block. They must be coordinated with the cylinder head, camshafts, fuel supply, and engine management, among other components.
Installing pistons and crankshafts requires specialized measuring tools and knowledge of engine tolerances. Check cylinder bore, bearing clearance, piston ring clearance, axial play, and all specified torque settings.
Use new gaskets, locking agents, and bearings where prescribed. Ensure proper lubrication during assembly and follow the break-in and maintenance instructions from the parts or engine manufacturer after the overhaul.
