How to Service the Hydrostatic Drive on a Garden Tractor

The hydrostatic drive transmissions often found in lawn tractors operate on hydraulic principles, as opposed to the system of belts and tension mechanisms found in manual or automatic transmissions. Therefore, hydrostatic transmissions must have a large oil capacity for self-lubrication, allowing the tractors an almost countless number of gear gradients, which also eliminates the need for constant depression and release of the clutch. Lawns and landscapes requiring difficult turns and frequent changes of speed are well served by a mower with a hydrostatic transmission. Because of their reduced burden on engines, such transmissions are also credited with emissions reductions. To maintain sound operation, the hydrostatic drive should be attended to regularly.

Things You'll Need

• Oil

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Instructions

1. • 1

     Check the oil level of the transmission. Depending on the model, the level should hover between 80 to 90 percent of total capacity, as some space is needed to provide for the fluid expanding when heated.

   • 2

     Examine the charge pump at the rear of the transmission pump. This component ensures that fluid transport is not disrupted. Locate any leaks or abrasions which might cause disturbance of oil flow.

   • 3

     Lubricate all parts of the linkage system -- the system that connects the gear shift controls to the drive system.

   • 4

     Put the tractor on a lift if it moves significantly while idling in neutral. Use your owner's manual to locate the linkage system from below. With the tractor idling, turn the linkage system's nuts until the wheels are still.