Issue link: http://read.uberflip.com/i/4040
40 SNOWEST NOVEMBER 2009 When something goes wrong with the drive belt on your sled, you know it. You can either feel something is amiss or you can hear it or both. e snowmobile belt is perhaps one of the most important pieces of equip- ment on a sled. Without it, you're not going anywhere, unless you're being towed. A belt can experience any number of different failures that can cause it to lose its ability to get power to the ground. We asked the tech people at Carlisle (www.carlislesnowbelts.com) to bring our readers up to speed on what those belt issues might be and what you can do to fix it. Carlisle covered just about every belt problem we could think of. Glazing e belt has been overheated, causing it to look melted and shiny in appearance. Glazing is usually caused by belt slippage due to an oil contami- nated belt, inadequate belt break-in or improper gear ratio selection for the application. Ensure that the drive system is set up properly for the rider and applica- tion; consider a lower gear ratio. Make certain that the clutch sheaves and belt are clean and free of contaminants. Problem: belt glazeD eXcessively or baKeD aPPearance Possible cause - Excessive slippage caused by insufficient pressure on belt sides Solution - Check primary clutch for smooth actuation Possible cause - Slippage caused by excessive horsepower (modified sleds) Solution - Consult dealer Possible cause - Excessive slippage from oil or moisture on pulley surfaces Solution - Check bearing seals and clean pulley Possible cause - Insufficient pre-load on secondary driven spring Solution - Repair/replace worn out clutches. Weak or broken springs can cause insufficient pre-load Possible cause - Excessive operation in low gear Solution - Inspect converter Hour Glassing A belt that is worn narrow or uneven in one section is commonly re- ferred to as "hour glassed." Hour glass- ing is a result of heat that is generated when the drive clutch is spinning and the belt remains stationary. is type of failure can be caused when a belt is too short, belt-to-sheave clearance is incorrect, belt deflection is inadequate, an improper gear ratio is selected or the drive system is locked and/or jammed. Verify that the correct belt and gear ra- tio are being used; adjust deflection and ensure that belt-to-sheave clearance is correct. See that the drive system moves freely before installing a new belt; repair if needed. Problem: belt Worn narroW in one section Possible cause - Secondary seized or not functioning properly Solution - Repair or replace secondary and replace belt Possible cause - Excessive idle speed Solution - Reduce idle speed and replace belt Possible cause - wExcessive slippage in primary caused by locked track Solution - Rotate track by hand until free. Replace belt. Disintegration Belt disintegration is the result of major abuse, lack of maintenance and/ or a belt used beyond its capabilities. A pre-ride checklist should include check- ing the drive belt for loose cords, cracks or defects. is type of failure can be caused by different belt conditions such as: hour glassing, glazing, broken cords, flex cracks or misalignment. Verify that the correct belt is being used. Check deflection and belt-to-sheave clearance. Ensure that the proper gear ratio is be- ing used and that the belt and sheaves are clean. Verify integrity and adjust- ment of motor mounts and torque stop. Problem: belt Disintegration Possible cause - Excessive belt speed Solution - Reduce engine rpm at high speed Possible cause - Clutch misalignment causing belt roll-over Solution - Align clutches Possible cause - Excessive slippage/heat built up in belt Solution - Inspect converter Possible cause - Excessive operation in low gear Solution - Inspect converter