This original oil pump piston (pump piston), also known as the oil pump spindle, is a key functional element inside the chain lubrication system (oil pump) on the legendary STIHL 041 chainsaws. Its primary technical role is the axial-rotary pushing and precise metering of oil from the tank directly to the guide bar and the saw chain. The spindle is driven from the crankshaft or the clutch of the machine, and with its precise stroke it ensures a constant and correct flow of oil during operation. Fitting this original OEM part, produced to extremely low tolerances, ensures reliable lubrication of the cutting tool, prevents overheating of the guide bar and eliminates the risk of premature wear of the pump drive gear. When overhauling and replacing the oil pump spindle, the whole clutch and sprocket cover assembly must be carefully dismantled. It is necessary to completely clean the pump housing of crusted sawdust, resin and old, thickened oil, because even the smallest impurities can block the operation of the spindle and cause it to break or damage the drive teeth. Before fitting, lubricate the new spindle generously with clean chain oil or a dedicated grease. When inserting it into the housing, check the condition of the sealing oil seals and rubber rings (O-rings) and replace them if they show signs of stiffness, in order to prevent oil leaking inside the chain cover. Key features Part type: Original part (OEM) Catalogue number (OEM): 1110 647 0601 (11106470601) Installation position: Oil pump mechanism / near the clutch (Oil pump, Clutch) Function: Rotary-thrust piston for metering and distributing chain lubrication oil Material: High-quality steel with induction-hardened working surfaces and thread Unit of measure: Sold per piece Compatible models STIHL chainsaws STIHL 041 G STIHL 041 FB STIHL 041 AVQ STIHL 041 AVEQ STIHL 041 AVFBQ