The LiftMaster 71-65LIMIT18 LIMIT SPROCKET DC MOD KIT, 18T is a replacement limit sprocket kit designed for LiftMaster DC motor operators that use a chain-driven limit assembly. The 18-tooth sprocket drives the limit chain that turns the open and close limit cams, allowing the operator to accurately stop the door at its programmed travel points. This OEM-style component helps restore precise limit control on commercial and industrial overhead door systems where the limit mechanism is mechanical/chain-driven, making it a practical choice for maintenance, repair, or upgrade of compatible LiftMaster commercial door operators.
As an 18T DC modular limit sprocket, this kit provides the tooth count required for proper limit ratio and smooth, repeatable door positioning on select LiftMaster DC operator platforms. Typical applications include sectional and rolling steel doors in facilities that require reliable daily cycling. Installation generally involves removing the existing limit sprocket, transferring the chain, setting or reindexing the limit cams, and reprogramming/verifying open/close travel per the operator’s service manual. Always disconnect power before service and confirm compatibility using your operator’s parts diagram or manual; after installation, test all entrapment protection devices to ensure UL 325 compliance. Common search terms for this item include LiftMaster limit sprocket, 18-tooth limit gear, DC limit kit, and commercial door operator replacement part.