Find your mojo again By the staff of Dirt Wheels
There was a time when it was fairly rare to replace the CVT drive belt on a 4×4 quad, but now some of these models are very powerful and come with large and aggressive tires. What we need here is some good TECH: to remedy the situation.
Plus, owners are riding them harder and punishing the CVT and its belt with high-load situations like mud-running and using track systems.
In our case, the belt on our Polaris Scrambler S let go while racing, so it was being ridden hard with no thought to belt life. Even though this is a 1000cc machine, changing the belt should be roughly the same on any of the Polaris twin-cylinder 4×4 quads.
1. On a Sportsman or Scrambler twin-cylinder 4×4 quad, the CVT belt case is under the rear part of the body. To get to it, you will need to remove this frame tube.
2. We could get an impact on the top bolts, but had to use a ratchet to get to the lower bolts. The same is true when you need to replace the bar.
3. There are a lot of screws holding on the belt case. We could get to a lot of them with this cordless drill, thanks to the slim 1/4-inch-drive tools, the extension, and a flex connector.
4. Some of the belt-case screws are difficult to get at. This one is under the seat, and it can only be reached with a wrench. The screws don’t take a lot of muscle to loosen, though.
5. Some of the screws near the bottom are also hidden in spaces that are quite a challenge to reach. We used both a 10mm GearWrench ratcheting wrench and a 3/8th box-end wrench.
6. Unlike most of the Polaris UTV CVT cases, the Scrambler CVT case uses these screws. They thread right into plastic, so you have to go easy on them.
7. With the screws out, we started working the belt case off. As soon as we could look inside, there was evidence of belt carnage with pieces sticking out at odd angles.
8. The belt shredded, so there were tough cords tangled in both of the CVT clutches. We had to use various pliers, a knife, and 30 minutes to coax all of the random parts and cords out.
9. The bottom clutch is at full spread when it is stopped, so you start the install by slipping the belt into the bottom clutch first. Work the belt up towards the top (secondary) clutch.
10. Use the Polaris tool to spread the sheaves as far as you can so you can start working the belt into place. The Polaris tool works well.
11. Get the tool locked in to spread the sheaves, and keep both hands free to work the belt on. We found it necessary to turn the primary with a tool to help work the belt on.
12. In this shot we have the belt just about completely onto the secondary. You must make sure that you aren’t getting your fingers in a position where they can get trapped.
13. Finally, the belt is on and everything is cleaned up. All that is left is to replace the belt case and install and tighten the screws. Finish up by installing the bolt-in frame section.
This is not a repair we would like to perform on the trail. We would if need be, but we wouldn’t like it. It would have been easier to clean the junk out of the sheaves if we had pulled the clutches off. Unfortunately, with our puller, we would have to remove a rear wheel, part of the rear suspension, and one of the rear axles.
We chose not to do that. Remember that you will need to break in the new belt to make sure it lasts. Ride the machine under half throttle for 20 miles. Don’t climb any steep hills or put a load on the belt. Stop and allow the belt to cool a few times. After break-in, you should be able to run the belt hard.
For more information on how-to stories, go to this link below:
To subscribe to Dirt Wheels Magazine in print or digital form click here https://hi-torque.com/product/dirtwheels.