I've been looking for something a bit larger than my old reliable 024 and came across a great deal on an 026. It wasn't running but is in great shape -- clean, nothing missing or broken, piston is clean with no scoring. $100 and 15 minutes away. A no-brainer. The seller said the last time he used it, it started right up, then died. He had replaced the carb several years before.
What I found:
The carb was way out of adjustment. In particular, the low jet was backed out 3 turns or more.
The spring in the air filter that holds the choke butterfly open was unhooked.
What I did:
Drained the fuel and replaced it with fresh canned fuel.
Fixed the choke spring.
Set the jets open 1 turn each.
Checked the spark -- OK.
Still wouldn't start.
A squirt of mix in the the carb and it started on the 1st pull, but wouldn't continue to run.
Pulled the carb, which looks like new, but is presumably Chinese. No markings of any kind on it. Opened it up and pulled the needles and cleaned out the passages as best I could. Put it back together and it starts and runs.
But...and here's the question: The tuning doesn't seem right. The idle adjustment needs to be bottomed out to get an idle and only if the low needle is closed a bit more than the point that gives good throttle response. Thinking maybe it was just the way the adjusting screw is mounted, I compared the butterfly position of the properly adjusted 024 to the position of the 026 -- the 026 is open much more than the 024 at idle.
The saw runs strong -- I've been testing on a 16" oak that we cut down recently. The saw has 16" bar and .325 chain. Even without a side-by-side comparison, it clearly has more oomph than the 024, with the same bar & chain.
It also seems to use more fuel than I'd expect.
My first thought was a vacuum leak, but I'm also suspicious of the carb itself. Any advice before I make up the parts to do a vac/pressure test?
What I found:
The carb was way out of adjustment. In particular, the low jet was backed out 3 turns or more.
The spring in the air filter that holds the choke butterfly open was unhooked.
What I did:
Drained the fuel and replaced it with fresh canned fuel.
Fixed the choke spring.
Set the jets open 1 turn each.
Checked the spark -- OK.
Still wouldn't start.
A squirt of mix in the the carb and it started on the 1st pull, but wouldn't continue to run.
Pulled the carb, which looks like new, but is presumably Chinese. No markings of any kind on it. Opened it up and pulled the needles and cleaned out the passages as best I could. Put it back together and it starts and runs.
But...and here's the question: The tuning doesn't seem right. The idle adjustment needs to be bottomed out to get an idle and only if the low needle is closed a bit more than the point that gives good throttle response. Thinking maybe it was just the way the adjusting screw is mounted, I compared the butterfly position of the properly adjusted 024 to the position of the 026 -- the 026 is open much more than the 024 at idle.
The saw runs strong -- I've been testing on a 16" oak that we cut down recently. The saw has 16" bar and .325 chain. Even without a side-by-side comparison, it clearly has more oomph than the 024, with the same bar & chain.
It also seems to use more fuel than I'd expect.
My first thought was a vacuum leak, but I'm also suspicious of the carb itself. Any advice before I make up the parts to do a vac/pressure test?