Saturday, May 4, 2024

Repairing Oiler on Husqvarna Chain Saw

  Two weeks ago I was using my 20 inch saw and noticed that the chain was not being oiled. That isn't good, but, I knew what the issue was. Since I already had my tools out to fix another piece of equipment, I figured it was a good time to fix the saw.

  I mostly use this saw for milling lumber, it has a special narrow ripping chain installed now. But I  also use this saw when I need a longer bar and more powerful engine for big cutting jobs. So, the first thing to remove was the milling guide. (A Granville Mill)


   Next, remove the cutting chain and the bar. Chainsaws all use the same size nuts to hold the bar and chain in place and they usually come with a three-in-one tool that has two sockets (one for the bar and one for the spark plug) and a flat head screwdriver.  The parts I need to get at are under that gray plate, under the clutch. So the next thing to remove is the circular clutch assembly.


   To remove the clutch you need to immobilize the piston so that the engine doesn't just turn when you try to unscrew the clutch assembly. There is a great hack to do this. 

  You turn the clutch until the piston is all the way to the bottom of the cylinder. Once that is done, you pack the cylinder with rope. This prevents the pistol from moving too far when you crank on the clutch to unscrew it. I crammed about 12 inches of 3/8 inch rope into the cylinder.


   There is probably a special tool for this that a proper shop would have, but pump pliers and a vise-grip pliers work just as well. The clutch is marked with which way to turn it to remove. Just unscrew it like the lid to a large jar. It has reverse threads so Righty Loosey, Lefty Tighty


   The clutch is in two parts. There is also a roller bearing on the shaft that slides right off. All that gunk has to be cleaned off before you remove the access plate.


   Under the plate is the auto-oiler. All that gunk is why it isn't working and that all needs to be cleaned out. A small flat head screwdriver, a tooth brush, rags, and copious amounts of gas are used to clean all this up.


   Then, it looks like this. That linear gear is turned by a plastic piece in the access cover plate. This works like a worm-gear, the two parts are at 90 degrees to each other. The linear gear turns a small pump, the square black plastic piece and the oil is pumped through the plastic tube going up and to the left.


   The clean access plate goes back on and is held down with just one screw. The plastic worm-drive, the black disk on the shaft, can be seen here as I reassemble all the clean parts. 


   The clutch goes back together in the opposite order from the removal process. There are two notches in the bottom of this part that fit over the worm-drive. The two pliers trick is used again to screw it down. You don't need to crank it down really tight, it will tighten up as it is used since it has reverse threads. 


   The bar and chain get reinstalled. While I had it all apart I cleaned the air filter, the spark plug, and used high pressure air to clean off all the other parts of the motor. It won't stay clean long, but I clean it good two or three times a year anyway.


  Start the motor and rev the engine for a bit and voile, oil is now flowing to the chain.

 



   Some thrown oil on the driveway is more proof the chain is now getting enough oil. Good job and I saved myself at least $100 and two weeks of time by doing this repair myself.