The John Deere STX 38 is a hydra-drive tractor. The hydra drive is a variable hydraulic-pressure drive unit driven by a V-belt from the engine to the transmission. John Deere uses belt part number M118760, which is 97.84 inches long and 0.5 inches wide. When the installation is described, it is from the operator's point of view while seated. Refer to the link in Resources for an illustrated view of the location of the components.
Instructions
- 1
Remove the spring on the belt tensioner. This is the flat pulley that swings in against the belt. Take the spring out, using pliers, where it connects to the tensioner pulley arm. Remove the spring on the parking brake latch bolt arm. You can see the long bolt from the body to the parking brake arm. Pull the spring off, also using pliers, where it attaches to the arm. Use a wrench to remove the latch bolt nut from under the arm.
2Removed both tie rods from the steering shaft arms, using a wrench to take off the nuts. Remove the belt now that the tensioner is loose. Pay attention to the belt routing.
3Install the new belt with the side opposite the tensioner running straight from the engine pulley to the transmission pulley. From there it runs to the idler V-pulley, around this pulley with the V-groove in the pulley to the tensioner located in the middle between both sides of the belt. The back side or smooth side of the belt goes around the tensioner pulley.
4Place the parking brake bolt through the parking brake arm and install the nut. Install the spring onto the end of the arm, using pliers. Install the tensioner spring onto the tensioner arm using pliers. Install the tie-rod ends onto the steering shaft arms.
