I need some help with my 026. I rebuilt the carb this summer after I picked the saw up. Got it tuned up and cut a few truck loads of wood with it. All was well. It sat for about a month and I went to cut some more wood. It was slow to rev and as soon as it built up speed it would fall on its face. I fiddled with the carb for a while and couldn't get anywhere with it. I put it up and grabbed another saw for the day. Ended up taking it to a local Stihl dealer that said they would tune it for me for little to nothing. They were unable to get it in tune as well and ended up throwing a new carb on it. That's another story. The mechanic told me after he replaced the carb he took it out and made some test cuts and it was running fine. Today, three days later, I take the saw out to cut some wood and it's doing the exact same thing. Any guess as to what my problem may be? Could it get that far out of tune after only two days? It was also a PITA to start, at least 10 pulls. Running fresh ethanol free gas with Stihl Ultra at 50:1. Thank you.
No way it would be out of tune like that. Check the basics, like impulse line and fuel line to make sure they aren't cracked or perished and throw a new spark plug in. Make sure the tank vent is working properly.
I'll check them out tomorrow after work. Wilson Bros on Southland Drive. They were suppose to call if they did anything other than adjust the carb. The owner was behind the counter when I went to pick it up. He made the situation right; only charged me cost of the new carb. He first told me to just take the saw back and pay him nothing but I didn't feel right about doing that.
Never dealt with Wilson, mostly with Central as they also sell Echo and Shindaiwa and a couple of times with Purdon (not sure they are still a dealer) and Bypass in Winchester.
Usually when a saw is slow to rev it is lean on the low jet. Also if it falls on its face when it does rev up then the high is lean. Maybe a pressure test of the crank case needs to be done. Especially since the carb was replaced and adjusted and now doing the same thing. I usually do a compression check also just to rule out any weird symptoms.
They're good people over at Central. They're both equally close to where I work but Wilson's is closer to where I live. They're more mom and pop style than central. Bevin's out Georgetown Rd is also a good spot for parts if you're ever out that way.
Have you tried tuning the carb yourself. I would count the number of turns by turning them all the way in and then bring the jets back out but add a extra 1/2 turn and then see if there is any improvement.
I had a saw act all wacky and a new carb fixed it but it sounds like it didnt yours. I would check rubber as well but could be a leak?
Would I be better off pulling the clutch and fly wheel and pressure checking the crank seals before I pick up a vacuum kit?
I haven't tried to adjust this carb, the mechanic said it was cutting fine when he gave it back to me. I'll see how far out he has the H and L screw before I do any pressure testing.
First thing I'd test with it is the fuel line. A failing fuel line can be inconsistent in the manner you described depending on how much fuel is in the tank, saw position, etc...
Agreed, but brutal if the dealer didn't catch it and popped in a new carb hoping for the best - I'd ask for the old carb back too! Cheers!
I forgot there was a special heifer sale tonight after work and just got home from the stockyards. The oh26 will have to wait until tomorrow. I'll check the fuel line first. If that's what does it I will definitely be going back to the dealer. Thanks for all the help so far.
All the OP has to do is pop the cap and run the saw to see..... If the saw runs great and begins to malfunction again, then pop the cap and ..... Runs good, vent problem. Same issues? Back to the drawing board.
Pretty sure it isn't a tank vent issue, haven't heard any pressure letting off when opening the cap. Also didn't have gas come gushing out of the fuel line when I rebuilt the carb. I'm heading out of town for three days for work. Hope to be able to get into it over the weekend.
