How to Lubricate a String Trimmer Shaft
- 1). Place the string trimmer on a convenient work surface. Pull the spark plug wire from the spark plug to prevent accidental starting.
- 2). Locate the gearbox on the end of the aluminum drive shaft housing just above the trimmer head. Loosen and remove the screws holding the gearbox to the shaft housing with a screwdriver.
- 3). Remove the gearbox and attached trimmer head from the shaft housing.
- 4). Pull the flex drive shaft from the shaft housing.
- 5). Wipe down the flex drive shaft with a rag. Remove as much of the old grease and any dirt or debris as possible. Wear a pair of gloves for hand protection.
- 6). Apply a thin coat of shaft lubricant to the entire length of the flex drive shaft. Use a rag, if necessary, to help apply the lubricant.
- 7). Insert the flex drive shaft back into the shaft housing. Slide the gearbox back onto the shaft housing and secure it with the screws that you previously removed.
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