Small Engines (Lawn Mowers, etc.)/Troy bilt n689 lawn tractor


My 9 yr old tractor will not move.  When started  I put in speed HIgh and forward  but the tractor jumps along as if a brake is on.
Then i smell belt rubbing,   .  I cannot see anything broken but when shifting speed it seems free.  When off  and brake released, in neutral I could push it yesterday, but it is "locked up" today


Those are pretty reliable transmissions...never seen one fail.

What does fail are the belts and the Pulley assembly PART NUMBER: 656-0059A

Parts link:

The first thing I would check it the brake.  They are prone to rusting and will not work right.

I would remove the part that holds the brake pucks/pads held on by 2 screws.  This will release all the brake pressure if it is binding.  Behind the brake puck is a metal plate...DO NOT loose the metal plate if the puck falls out.

See if it will roll with the brake assembly removed.  If so, the little dowel pins are sticking.  You will need to remove the pins, clean with a wirebrush or sandpaper.  Clean the pin holes as well.  I use a small drill bit with steelwool on the great.

Lightly grease the pins and re-install everything.  Re-adjust the brake.  To adjust, I set the parking brake and turn the adjustment nut until I can't push the mower.  Release the brake and make sure you can easily roll it.  Adjust as necessary.

After you know the brake is working right then I would start by replacing the belts.  When replacing you will have to remove the variator pulley.  Inspect the bearing in the pulley and see if they are in good condition.  I would lightly lube with grease.

Let me know what you find.


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Eric A. Jones


Lawnmower Repair . Certified Master Service Technician from B&S. Have 23 years experience on B&S, Lawn Chief, Weed Eater, Echo, Peerless, Wheel Horse, Snapper, Atlas, MTD, McCulloch, Homelite and many other numerous brands. Specialize in electrical repair.


Born and raised in the midwest. Started tinkering with engines when I was about 14 on my Suzuki RM-80. I began lawn mower repair at a small hardware store. I knew absolutely nothing. I read lots of repair manuals and met an older fellow who taught me many lessons. I continued working on small engines through high school and paid my way through college working on mowers at the same hardware store. Decided to get away from the midwest and mower repair so I joined the Air Force. I repaired air traffic control electronic equipment and ended up in Hawaii where I got a part time job at Small Engine Clinic. I gained a lot of experience from the Small Engine Clinic and had a blast repairing small engines. I then took the Briggs and Stratton Master Service Technician test and earned my MST. I then traveled to Wisconsin where I attended the factory update training seminar and received formal training. Continued working on mowers part time as I completed 20 years of military. Retired from the military on a Friday and continued in the lawn and garden industry the next Monday.

MAS Aerospace Operations BA Mathematics AAS Electronic Communications AAS Electronic Technology

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