The clutches and belt are one of the most-important systems that determines how well a snowmobile runs. If they’re dirty or out of adjustment, a snowmobile won’t perform to its potential. Here are five tips to maintain or restore a sled’s drivetrain.
- To help the drive belt hook up, regularly scour the clutch sheaves with emery cloth in a straight pattern from the clutch hub to the edge; do this with light pressure. This removes belt residue, which is slippery and holds heat, and resurfaces the sheave. It’s important to rinse the clutch with warm water because metal dust is abrasive and it will accelerate wear to rollers and bushings.
- Clean the edges of the belt with a wire brush or emery cloth to remove glaze. New belts usually have slippery residue from the mold used in manufacturing, so this needs to be removed for the best performance. Clean the edge with acetone, too. Belts become conditioned, so reinstall it in the same direction for its full life cycle to help it last longer.
- Keep the drive belt adjusted within specification. Proper belt deflection is imperative for good, efficient performance. Most secondary clutches have an external adjuster that affects the distance between the moveable and fixed sheaves, which sets the belt’s tension.
- Make sure the clutches are aligned. Aligned clutches assure that the belt rolls straight and does not bind. A straight belt also allows for the most surface area for the belt to contact the clutch sheaves; more contact means more drive belt traction and efficiency.
- Check the belt-to-sheave clearance. The gap between the belt and primary clutch’s moveable sheave is crucial for a smooth engagement and long belt life. Measure this only with the engine turned off. The distance is adjusted by adding or removing shims inside the clutch and should only be done by a professional with proper tools and specifications.