Need some help with an 026 Pro

[K7NUT]

I know there is a lot of knowledge here and I have an 026 Pro that is kicking my butt. A little history, this is a friends saw he obviously bought used and he has run it for awhile, ran fine, but the day I showed up on his project, it sounded to me like a buggered carb, he not being a mechanic, gave it to me to rebuild the carb. While I had it, we decided to put a new P&C on it(I did my 066 not long ago), so we got Meteor brand and crankcase seals. I installed all that and did a P/V test on the crankcase, both were great, no leaks, I rebuilt the carb, then also V tested the fuel/impulse lines, solid, but it still was pumping gas out the muffler!? I bought a chinese carb of amazon, thinking the carb was bad, but the ***** carb did the same?
I moved to the spark, put a new spark plug wire on it and Ohmed the secondaries, it showed 8.23K, which was in spec. I even played with the plug gap and coil gap off the flywheel, but when it runs, it’s bogging like it’s flooded, barely running at WOT and gas(black from soot)puking out the muffler.
One thing I have noticed on rebuild kits, is some have two needles, long and short? This one had the shorter one in it when I rebuilt it and this kit only had a short one in it, so thats what I put back. Another thing, I read many of you mention V testing the carb? I do not know how yet, need to read up on that, so that has not been done. I took a few pics, if there helpful, but, what am I missing here guys, is this just another OE(operator error)?

 

[Homer6679]

Metering lever in the carb out of spec?

An 026 Pro should have a carb with a LOW and HIGH needle for the carb not a single needle similar to ms170 carbs. Without the needle the jet is wide open essentially allowing as much fuel as possible.

 

[K7NUT]

I guess I need to learn more on the carb, but this carb only has a L needle, the H side is plugged from the factory?
Even has a rubber boot with one hole for the L adjuster only. Must say, wasn’t familiar with just a L side adjustability on a saw?
I looked up setting the metering level, but I do not have one of those “W” gauges, I will check the manual, maybe it has a setting?
So it may be OE…I have no idea where it should be, but it would appear it’s to high?

 

[Aknutter]

Get a walbro wt-194
Use oem air filter
Go to walbro website and search the tech info for adjusting needle lever and p/v testing.
Is the spring under the lever?
Try a different spark plug, sometimes they are defective or junk.

 

[a. palmer jr.]

Yeah, I don't think that's the right carb for that saw. It shouldn't leak anyway unless you left the spring out of the lever assy. or you put the short needle in it when the long one was specified.

 

[94 wrangler]

I had a similar problem not long ago on my 026 . It turned out to be the Chi-com after market air filter. It's spring on the choke shutter was too weak and it was closing or rather choking the carburetor under full throttle. I put on a new OEM air filter, problem was gone! Some say just to change out the weak spring and reuse the OEM spring. So in short, if you have a after market air filter toss it or change the choke spring in between the two halves of the filter with your old OEM spring.

 

[Aknutter]

Try this

 

[stihltech]

The original carb in the pictures is correct for OEM. I know some on here don't like it. This is the one with one outlet hole in the muffler. Adding two more wakes the saw right up.
You have checked spark with a wide gap, correct? Forget the ohmmeter, output is what makes the saw run.
Pressure testing the carb answers a lot of questions as to flooding.
And yes, dump the choke spring in the Chinese air filter for an OEM one. I won't let one out the door without doing it.

 

[Kevin in Ohio]

I've had quite a few saws that would idle but when throttle applied they would die off or do nothing. If I knew the carb was good, almost every time it was a failing or weak coil/condensor. Get a solid state and dump the points and condensor would be my suggestion.

 

[K7NUT]

Thank you guys for all the help and I am going to pulldown that manual when I fire up my laptop. I have to say, you were correct on the metering level. I do not, nor have I ever had one of those Walbro gauges, so I’m sitting here wonding, how the heck I rebuilt so many carbs in the past…and they worked!?
I have one, both, W & Z coming from amazon, so I have to wait, but in the mean time, I watched a YT vid on setting a Walbro level and when I got home from work, I yanked the 403 off and lowered the tab…she fired right up, but still rich, so I will pull it out and keep figiting with it, it has moved from frustrating, to a quest!
So bottom line…it was Operator Error, thanks so much guys, I will let you know how it goes.
And according to the Stihl 026 manual, the 403A goes to one 026, the Pro and this is a Pro.

 

[K7NUT]

Well, I tried and tried with the stock 403A carb, but I could not get it to run with it, no matter where I put the level?
So just for S&G’s, I took apart and checked the chinese carb from Amazon and set the L to 1 turn out, H to 1 1/8, stuck it on and pulled. She fired right off, had to do some fine tuning on the L H & idle, but thats to be expected. Since it has a new P&C, I didn’t run it more than 15 min runs, bucking up some limbs the snow/ice took down…man it ran like a scolded ape! There must be something wrong with the 403A, but it’s working now. I will return it to my friend tomorrow and my W&Z gauges are supposed to be here Wednesday
Again, thank you all for your help, I learned something.
View attachment IMG_3023.MOV

 

[stihltech]

Good that the A/M carb is working. Once in a while there is a good one.
Pressure test is what is needed on the carb inlet.
Went back and read original post. My first thought would be the choke in the air filter. I would still check it.
The high speed jet can wear in the original carb. Had that happen.