Operating Instructions25Engine ThrottleThe throttle control lever (red knob) is located on theleft side of the seat and is used to control enginespeed. Moving the lever forward toward the FASTposition increases engine speed; moving it back-ward toward the IDLE position decreases enginespeed.Choke and Throttle LocationForward Speed Control (FSC)Forward Speed Control (FSC) has two functions:One is to set forward travel speed, and the other isto establish the NEUTRAL-PARK position. Whenthe FSC lever is moved into the FORWARD position,a friction lock holds any forward speed setting from0 to 5 mph (0 to 8 km/h). The ground speed is pro-portional to the lever position; the further the lever isadvanced forward, the faster the tractor moves. It isnot necessary to hold the FSC in position since thefriction lock maintains the selected lever position.Pulling back on the steering levers overrides theFSC setting and slows or stops forward travel.Releasing the steering levers allows the tractor toresume forward travel at the speed set by the FSClever. To stop and park the machine, the FSC leveris moved backward to the NEUTRAL-PARKposition.Steering LeversEach drive wheel is controlled by its own indepen-dent steering lever, for both steering function andFORWARD/REVERSE motion. The FSC lever setsthe maximum forward speed, and also sets the for-ward position of the steering levers. The steeringlevers operate only with a backward pulling move-ment of the lever, which causes the drive wheel forthat lever to first slow down, stop, and then reversewith a full backward lever stroke. The levers arereleased to the FORWARD position for “straight-ahead” ground travel.NOTE: Pushing forward on the steering levers willnot cause any change in tractor motion - there will beno steering lever reaction and there will be nomachine damage.Blade Clutch (PTO)The blade clutch lever is located on the right side ofthe seat behind the right fender and is used toengage and disengage the mower blades. The bladeclutch has two positions. Pushing the lever BACK-WARD engages the PTO that drives the mowerblades. Pulling the lever FORWARD disengagesthe PTO and engages the blade brake.NOTE: On GHS equipped models, the Powerfilmotor and Grass-Pak full signal switch are acti-vated by engaging the blade clutch. Refer to Usingthe GHS Catcher in this section for a completedescription of GHS operation.Parking BrakeThe parking brake functions by locking a pin into thehydrostatic transmission pinion gear teeth. Movingthe lever FORWARD engages the parking brake;moving the lever BACKWARD releases the brake.IMPORTANT: Stop the tractor completely beforeengaging the parking brake. The parking brake usesa positive mechanical lock similar to the PARK posi-tion on an automotive automatic transmission. If thetractor is moving when the brake is engaged, it willresult in sudden stoppage and possible internaldamage to the axle drive.NOTE: If pressure on the parking brake pin (e.g.parked on a hill) makes it impossible to release theparking brake with the parking brake lever, move themower gently forward or backward to release the pin.Throttle Choke