If you have an older chainsaw, you’ve probably heard it say this before: “Help, Help! cough, umpfh, vrooooommmmm! cough, sputter, death.” I’ll walk you through the steps of bringing a Stihl 026 chainsaw back to life.
Maybe I shouldn’t lead off with this, but my Husquvarna 55 has never given me trouble… Just sayin’.
Alright, some history. The 026 was given to me. Yes, pretty cool, right? It was in a box… In pieces… With enough oil impregnated swarf packed into each nook and cranny to make a dozen toxic candles. The first step was clear. CLEAN!!! Tooth picks, nylon brushes, and a steady supply of compressed air were the tools needed for this project. After replacing the spark plug and putting some fresh gas in the tank, she was purring like a kitten.
Fast forward about a year and things aren’t so dandy. Once the saw would turn over, it would immediately die. Nothing is more frustrating.
So what’s the problem? Well, I had a hunch that the carburetor needed to be rebuilt, so I tore it apart and what do ya know. The diaphragm was torn… This is obviously an issue. Lets hope it runs like a top when I get it back together.
I found my carburetor rebuild kit on ebay for less than $10. If you try getting these parts from your local chainsaw shop… Well lets just say you shouldn’t even bother calling because it will be at least 3 times more expensive.
Rebuilding a carb is pretty straight forward. Keep track of the way things come apart. Catch the spring that wants to go airborne from the needle valve. Give everything a good soak of carb cleaner and then reassemble. Easy, right? Well, just in case you like pictures as much as I do, you’re in for a treat.
Where’s the Carburetor?
Time for a Rebuild!
I start by removing the plate that covers the diaphram and pretty quickly see that it is well used. I remove the gaskets and lay them out in the order they were disassembled. Flip ‘er over and remove the other cover by loosening a single philips head screw. You will uncover a gasket and screen on this side. Again, lay them out in the order that they were disassembled.
There are still a few items to get to before we start replacing gaskets. The needle valve and fuel screen need to be cleaned or replaced. A word of caution. You remember that spring I mentioned earlier? You’re about to find it so don’t go all A.D.D. and pay attention. There is a rocker that is held in place with a philips head screw. Place your thumb over the side of the rocker that is closest to the center of the carb. Once you’ve removed the screw, that spring wants to hide under the pile of dust in your shop where you will never find it again. Slowly lift your thumb and collect the rocker arm, spring, screw, and needle. A magnetic tray is a great place for these to live until you’re ready for them.
With all of the gaskets and such removed, you’re ready for the carb cleaner. Soak this thing down and let the cleaner drain through all the passages and you should be good. Make sure to spray every nook and cranny. I did this step one morning before heading off to work. That evening I got into replacing the components. I’d let the carb sit at least 30 minutes to allow everything to dry off before reassembling.
Start with putting the screen back in (if you took it out). A pencil eraser works quite well to push the screen into place. The screen will (at least mine was) be creased a bit. Put the screen in place similarly to a coffee filter. Those of you that are Keurig only folks are just screwed unless you remember what a coffee filter is… I personally like the old fashioned percolator but that’s a bit off topic now, isn’t it?
I promise that’s the hardest part of this whole post. Moving on to gaskets. Basically you just line up the holes and lay them down in the opposite order that you removed them. Follow along with the pictures if you don’t remember. Also, I did actually put all four screws back, just not for this picture… Not sure why.
Alright! The carb is back together. Now just slam that bad boy on the saw and let ‘er rip! First on the list is to reconnect the gas line. The gas line is the longer of the two tubes. It hooks up the the black barb. Now is also the time to reattach the throttle wire. Any words I used to describe it’s orientation would be futile, so hopefully the picture will get you there.
The last step before slapping the covers back on is to reattach the throttle wire to the trigger. The throttle mechanism is a two part system which requires you to be gripping the handle to rev the motor. There is a spring that wants to poke your eye out. Push it down into the handle and place the remaining throttle component on top of the spring. There will be a little indention that will hold this spring in place. Once that’s done, reinstall the handle cover and you’re done.
As long as you didn’t turn any of the adjustment screws on the carburetor in the process, you should be good to go.
Unfortunately my troubles did not end with the carburetor rebuild. The saw was dreadfully low on compression and would not run.
I discuss how to completely rebuild the crankcase and top end in my post A Dying Chainsaw’s Last Words: Top End Rebuild.
Thanks for reading, and feel free to leave any questions or comments.