Slipping Motor Drivebelt Repair – How to tighten

Okay, today we are going to address what seems to be a common issue: A problem with the motor or drivebelt slipping. It’s a little tricky to explain how to fix things for all treadmills in general because all treadmills are different. But, I will explain it as simply as I can, and if you run into something that looks a little different than I explain you may have to use your creativity.

The motor drive belt can slip from several different things. It usually happens after using the treadmill for a while. To make sure you know what the problem is, take off the cover of the motor, walk on your treadmill slowly and try to stall the belt. Make sure you be careful! When you stall the belt, you can see more what’s going on. If the motor and drivebelt and front roller keep moving, but your treadbelt isn’t, then your treadbelt is simply slipping on the roller. If the drivebelt keeps moving, but the roller stops, then you probably have a broken front roller pully. If either the drivebelt, or front roller stall, then the problem is indeed with the drivebelt.

Sometimes this problem can be fixed by tightening the belt, rather than replacing it, but this is risky because it can often cause problems that would be more expensive than fixing the belt. So my advice would be to just replace the belt to be safe. However, I’m going to explain how to tighten it.

Unscrew everything that you need to unscrew. Find the motor mount and loosen it. Whether it’s an auto tensioner or a single jack bolt, you’re going to need to loosen the motor mount to adjust things.

Then find the set bolts. These are usually on the motor mount. Sometimes they’re on both sides, sometimes they’re only on one side. You will need to loosen those, but don’t take them off.

If your engine has a tensioning bolt that will tension the engine. Tighten that. It usually runs parallel to the belt, so you can identify it. Most likely your treadmill won’t have one of these, since most do not. But if you’re lucky your may. If yours doesn’t have one, skip to the next paragraph. If it is there you will only need one person to tighten it. Just give it a few turns using whatever size wrench you need. Usually it’s 7/16″. After you adjust this, tighten up the other bolts and try it out. See if it still slips. If it doesn’t. Good job! If it does, loosen those other bolts again and try tightening it some more. If it still slips, then heck with it. Just get a new belt.

Okay, if you don’t have a nifty tensioning bolt in your treadmill you will need to tighten it by hand. You will need 2 people for this. One person will apply tension to the belt while the other will tighten the set bolts (the bolts on the motor mount that you had to loosen). Then tighten up the motor mount again and try it out. If it works without slipping, Good Job! If not, loosen the bolts again and stretch the belt a little more this time. Then try it again. If it still slips then you’re going to want to replace the belt.

Now when you’re at this point, do what I described in the 2nd paragraph again to make sure it’s the drivebelt (stall the machine and see what happens). If the drivebelt does indeed need to be replaced don’t get too bent out of shape. They only cost like $30 dollars or so. It’s better to replace it than to risk having a slipping or broken belt. That can cause major problems that would cost much more to fix.

Well, good luck. If you’re not familiar with what’s what in a treadmill, and this wasn’t quite detailed enough, I know there are some great youtube videos out there on how to fix most of these problems. You can also check out treadmill doctor’s troubleshooting page. They’ve got great information. Anyhow, good luck with it. I always think fixing my own stuff feels better than paying someone to do it, so kudos for trying to do it yourself. Just make sure to be careful and try not to break anything that would end up costing more than hiring someone to fix it.

See you next time!