Husqvarna 545, 545 TrioBrake, 550XP 550XP TrioBrake, 550XPG, and 550XPG TrioBrake chainsaw Ignition and Flywheel guide will help with any Ignition and Flywheel replacement, inspection and correct running of the chainsaw.

A Service Manual detailing the Ignition and Flywheel removal and refitting procedures with full diagrams, as well as more complete chainsaw repair information, is available to download. A Husqvarna 545, 545 TrioBrake, 550XP, 550XP TrioBrake, 550XPG, and 550XPG TrioBrake Parts List, Operator Manual, and Zama carburetor manual are also available to view or download as a PDF which can be read on any device or easily printed.

Dismantling the ignition module and flywheel

Fig 1

1

Remove the cylinder cover. Remove the starter. Snap off the ignition cable from the guide rail and remove the guide rail. See figure 1.

2

Fig 2

Knock out a few of the pins in the tool if it does not match up with the flywheel.

Use the tool to hold the flywheel in place while the flywheel nut is loosened using a suitable socket wrench. See figure 2.

3

Fig 3

Thread the mandrel on the crank pin. Screw in until 1-2 threads are left to the flywheel. Knock on the mandrel with a suitable metal hammer while at the same time pulling the flywheel outward until the flywheel comes off the shaft. Remove mandrel and flywheel. See figure 3.

Unscrew the air nozzle to replace the ignition module. Loosen the screws on the ignition module. See figure 4.

Dismantle the air filter, air filter holder and carburetor. See the “Dismantling the carburetor” chapter.

Dismantle the tank unit as outlined in the “Dismantling the tank unit” chapter.

Fig 4

Dismantle the intake system, see the “Dismantling the intake system” chapter.

Loosen the earth cable. See figure 11. Pull the cables through the openings in the crankcase.

Cleaning and inspection

• Clean all parts, especially the tapers on the flywheel and shafts.
• Check the flywheel for cracks or any other signs of damage.

Assembling the ignition module and flywheel

Fig 1

1

Run the cables through the opening in the crankcase. Screw the earth cable in place. See figure 1. Fit the cabling to the stop button.

2

Position the cable channel as outlined in figure 1. NOTE! Take care that the cable channel is positioned correctly under the ignition module so that the cables are not crushed.

3

Place the ignition module in position. See figure 3. Do not tighten the screws.

4

Fig 2

Fit the flywheel onto the crankshaft pin. Turn the flywheel until the key fits into the key slot on the shaft. See figure 2.

Tighten the screw for the flywheel.

5

Fig 3

Insert the plastic air gap tool, at a thickness of

0.3 +- 0.1 mm, between the lugs on the ignition module and flywheel. Turn the flywheel so that the magnets are positioned opposite the ignition module. Tighten the screws, at tightening torque of 4.5- 6 Nm. Remove the plastic air gap tool. Fit the intake system as outlined in “7.14 Assembling the intake system”, the tank unit as outlined in “7.16 tank unit”, and the air filter as outlined in “Assembling the carburetor”.

6

Press the ignition lead into the holder on the partition wall.

7

Then fit:

• • The air nozzle
  • The guide rail and press the cable in place
  • The spark plug hat by unscrewing the piston stop
  • The starter, at tightening torque of 2.5-3.5 Nm
  • The cylinder cover

Husqvarna 545, 545 TrioBrake, 550XP, 550XP TrioBrake, 550XPG, and 550XPG TrioBrake Ignition and Flywheel Repair