That dreaded “SNAP” followed by high revs is something that no rider wants to hear. A blown snowmobile belt is never fun, but it does happen. If it’s happening to you frequently, though, you have some bigger issues. There are a few reasons why your snowmobile belts keep blowing and some can be indicative of some crucial issues that need your attention right away. Listed below are some of the more common issues that will wear snowmobile belts prematurely. Use this as a guide to help diagnose your issue. Then you can stop leaving your sled behind and riding two-up with your buddy to go get a trailer after you’ve blown both your main and spare drive belts.
A major culprit for premature belt wear is clutch misalignment. Misaligned primary and secondary clutches will cause the belt to run crooked. Extra stress on the sidewalls of the belt is created by running crooked on the clutches. Your sled will blow through drive belts fairly quickly if the alignment is way off.
Checking clutch alignment is something that most riders can do at home and should be the first place to check if you’re sled is eating belts. And just because your sled is new doesn’t mean that everything is set perfectly. Even brand new snowmobiles can come with misaligned clutches.
Snowmobile clutches need to be aligned in three different areas. Each area needs to be addressed to prevent premature belt wear. The first alignment to check is the offset between the primary and secondary clutches. The belt needs to run straight between the two.
The second alignment is to ensure that the secondary shaft and the centerline of the crankshaft remain parallel under load from a top view. The final alignment is the same as the second but from a front view.
Use your snowmobile’s manual to measure alignments and for instructions on how to adjust them back to where they need to be. If you are not mechanically inclined, have a mechanic check out the clutch alignment for you.
Damaged clutches can also wear on a drive belt causing it to fail too soon. Check for more obvious problems first. Look for burrs, cracks and other irregularities on both clutches where the belt rides, especially on the sheaves. If the belt is constantly rubbing against or catching on something, it can deteriorate fast.
If you don’t see anything wrong where the belt rides, check for other problems with the clutches. Worn bushings, springs, ramps and rollers can all put a wobble in clutch. That wobble will make the belt rub funny on the sheaves and will speed up the wear on the belt.
Wrong Belt for Machine
Today’s sleds have a lot more torque and power compared to the one’s of old. That extra torque puts a lot of demand on the drive belt. Be sure that you are using a belt that can handle all of that. This is where the old adage of “you get what you pay for” comes in. You may find a belt that is the same size as your stock one for less, but it may not be rated for the capabilities of your snowmobile. Spend the extra money up front for a drive belt that is designed for your snowmobile and you will ultimately save more money by not having to replace belts as often.