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How to Install a Starter and Rewind the Spring on a McCulloch String Trimmer

Updated February 21, 2017

The recoil starter assembly on a McCulloch string trimmer is one of the most common repair issues operators face. This assembly contains a starter rope, pulley and recoil spring, which are housed in the starter area above the flywheel. To access the starter housing area, you need to remove the clutch and shaft. The recoil spring will also need tensioning to retract the rope. You will need to install the starter assembly if any of the assembly parts break or lose their efficacy.

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  1. Separate the power head from the boom. Unscrew the rear throttle trigger's mounting screw, on top of the rear handle, with the T-25 Torx driver. Pull the boom from the power head. Unscrew the air filter cover, on the side of the engine, with the T-25 driver. Remove the filter cover and filter to access the throttle cable and throttle arm on the carburettor.

  2. Disconnect the throttle cable wire from the carburettor. Unhook the throttle cable's Z-fitting with the needle-nosed pliers. Slide the cable out of the throttle arm on the carburettor. Unscrew the grip and clutch housing's four screws with the T-25 driver. Slide the grip and clutch housing off the clutch.

  3. Disconnect the two stop switch wires from their engine connections using your fingers. Pull them apart slowly. Unhinge the H.T. lead wire's rubber boot from the end of the plug. Disconnect the spark plug from the cylinder with the socket wrench and 5/8-inch socket.

  4. Insert the nylon rope into the cylinder hole where the spark plug was. Feed the rope in slowly while pulling out on the starter rope. Feed the rope in until the piston hits the rope and stops moving. Leave at least 3 inches of rope extending out of the cylinder hole so you can remove it.

  5. Unscrew the clutch drum with the T-25 driver counterclockwise. Remove the clutch drum from the crankshaft. Fasten the clutch removal tool to the clutch rotor's bolts. Remove the clutch rotor from the crankshaft. If you can't get the clutch tool, you can use a hammer and soft drift to lift out the clutch rotor.

  6. Unscrew the starter housing cover's four screws with the T-25 driver. Lift the housing cover slowly, reach under the cover and unplug the stop switch wires from the ignition module. Leave the throttle cable in the starter housing. Unscrew the baffle from the starter housing using the T-25 driver and slowly lift the starter pulley out of the housing area.

  7. Pull out the old recoil spring from the pulley using the T-25 driver. Inspect the pulley and spring for damage. Replace if the spring has straightened ends or the pulley's teeth are rounded. If you are replacing the starter rope, cut the old rope off and thread in a new one.

  8. Apply a fingertip's worth of grease to the post and baffle on the pulley and starter housing. Rewind the starter rope clockwise around the pulley. Set the recoil spring onto the crankshaft. Set the pulley on top of the recoil spring cartridge. Don't screw it down yet; hold your thumb over it to keep it steady.

  9. Withdraw about 10 inches of starter rope off the pulley. Wrap the segment into a loop. Pinch the loop in your fingers and wiggle it back and forth until the pulley catches onto the recoil spring. Wind the pulley, rope and spring clockwise five to eight times to rewind the spring. Let go of the rope and it should retract onto the pulley.

  10. Refit the starter cover housing over the starter assembly and tighten all for screws with the T-25 driver. Reinstall all other parts in reverse sequence.

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Things You'll Need

  • T-25 Torx driver
  • Needle-nosed pliers
  • Socket wrench
  • 5/8-inch socket
  • 10-inch piece of nylon rope
  • MTDSW clutch removal tool
  • 6-foot, 3/16-inch starter rope (if necessary)
  • Recoil spring (if necessary)
  • Pulley (if necessary)
  • Multipurpose engine grease

About the Author

Currently based in Minneapolis, Minn., Eric Blankenburg has been a freelance journalist since 2000. His articles have appeared in "Outside Missoula, Outside Bozeman," "Hello Chengdu" and online at and various other websites. He holds a Bachelor of Arts in creative writing from the University of Montana.

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