Replacing brake band on Husqvarna 357/359/340/345/350/346/445 and many others
Before attempting to repair any chain brake, eye protection should always be worn, these machines all have an out board chain brake, known as a knee link brake due to its actuating mechanism, start by makeing sure the brake is off, by pulling the brake handle fully back to the top handle, now remove the bar securing nuts, remove the brake/side cover, the hand guard stays with the saw, so the cover is quite difficult to hold when removing the spring, so take two 8 mm bolts, clamp the hex heads in a vice, spacing them out the same as the fixing holes in the brake, now fit the brake /cover band up onto the up standing bolts, use the two bar nuts to secure the brake to the bolts, now insert special tool part no. 502522202 into the actuating quadrant and turn to activate the brake ( this will remove much of the spring tention ) if you do not have the tool you can remove the hand guard from the saw and use that, or a sturdy pair of long nose pliers, now remove the cross head screws from the spring cover, edge the back of the spring up enough to insert a suitable screw driver into the end, lever the spring up and onto the screw driver shaft ( this will stop it flying out ) remove the c clip securing the actuating quadrant to the brake cover, gently lever out the roll pin in the anchor end of the band, the band will now lift out of the cover, remove the single cross head screw securing the knee link mechanism to the band. Refit the new band into the knee link and re fit the screw, re fit the quadrant onto the post in the cover and re fit the e clip, press the anchor end of the band back into the cover, insert the spring back onto the knee link spigot, compress the spring and push it back into the cover, the best way to compress the spring is to use a good pair of long nose pliers, push the closed jaws into the end of the spring ( this will stop the spring flying out ) now push the pliers in to compress the spring against the knee link, and back into the cover, refit the spring cover screws, you now need to load the brake before it can be put back onto the saw, use the special tool, or the removed hand guard to do this, it will take a fair amount of force to re load the brake, once loaded re fit to the saw.
on May 12, 2011 | Garden