If your snowmobile's recoil starter isn't working properly, this Kimpex replacement spring might be exactly what you need to get back on the snow. This is the rewind spring only, designed to replace the OEM part number 420939079. It fits a range of Ski-Doo models from 1974-1992 including the Alpine II, various Moto-Ski models from 1973-1986, and several Kohler engine models including the K618/2, K440/2, K295/2, and others. The quality is solid - Kimpex makes reliable aftermarket parts that meet or exceed OEM specifications. Installation requires some mechanical knowledge since you'll need to disassemble the recoil starter housing to replace the spring, but it's a straightforward job if you're comfortable with small engine repair. The spring provides the tension needed to properly rewind the starter rope after each pull, and when it wears out or breaks, you'll notice the rope doesn't retract smoothly or at all. This is one of those common wear items that can leave you stranded if it fails, so having a replacement on hand is smart preventive maintenance. Whether you're doing repairs in your garage or need a reliable part for your snowmobile fleet, this Kimpex spring delivers the quality and fit you need to get your machine starting properly again.