How To Restring A Troy-Bilt TB425CS

After enough use, your Troy-Bilt TB425CS trimmer inevitably will run out of string. With this model, which is one of the more reliable trimmers on the market, there are two ways to replenish string: using a prewound spool or winding new line along the inner reel. Installing a prewound spool usually takes only a couple of minutes but typically is more expensive than attaching new line. Rewinding with line you can purchase from your hardware store usually takes five minutes or less.

Step 1

Measure out 20 feet of line and cut this in half. Grasp the outer spool and rotate the inner reel in a counterclockwise manner so that arrows are aligned on the inner reel and outer spool. Remove any old line from the line loading and locking holes.

Step 2

Insert an end of one section of string into one of the eyelets on the outer spool. Keep pushing the line until it slides into the inner reel's line-loading hole. Loop no more than 1/2 inch of the line into the locking hole; then pull the line until it is snug.

Step 3

Use the same procedure as in steps 1 and 2 to secure the second line. Use a counterclockwise motion to wind the inner reel. Stop when 4 inches of line emerges from both sides of the outer spool.

Step 4

Unscrew the bump knob, pulling it off the spring and foam seal if you choose to install a prewound spool instead of winding on new line. Take out the inner reel and any remaining scraps of line.

Step 5

Take the two ends of line on the prewound spool and insert them through the outer-spool eyelets. Secure the new inner reel, with the arrow side facing up, onto the outer spool. Reattach the bump knob, spring and foam seal to the inner reel.

Step 6

Rotate the bump knob in a clockwise manner until it's snug. Free the lines from the inner reel's holding slots by pulling both lines.