Stihl 034 carb adjustment problem

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Maxi5566

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Carb model: C3A S4C 11D

i cannot adjust my saw correctly. My blade is either turning on idle or just die if I adjust LA or L.

any tips? It was working great last week, but I tried to adjust it to factory settings and now it doesnt work.

Another problem:
When I rev it up, theres white smoke coming from under the saw
 
Carb model: C3A S4C 11D

i cannot adjust my saw correctly. My blade is either turning on idle or just die if I adjust LA or L.

any tips? It was working great last week, but I tried to adjust it to factory settings and now it doesnt work.

Another problem:
When I rev it up, theres white smoke coming from under the saw
Can you tell us what you have done so far with adjustments? I'm not sure what you mean by LA. You should have one marked L and one marked H next to it. Near those will be the idle speed screw. By "blade" I assume you mean "chain". Can you tell exactly where the white smoke is coming from? Are you sure someone didn't put bar oil in the fuel tank?
 
Carb model: C3A S4C 11D

i cannot adjust my saw correctly. My blade is either turning on idle or just die if I adjust LA or L.

any tips? It was working great last week, but I tried to adjust it to factory settings and now it doesnt work.

Another problem:
When I rev it up, theres white smoke coming from under the saw
I wonder if it’s due to an air leak and it could be sucking in bar oil, though it does depend on the saw design, where is the smoke coming from?! Or have you accidentally put bar oil in the fuel tank?!
 
Can you tell us what you have done so far with adjustments? I'm not sure what you mean by LA. You should have one marked L and one marked H next to it. Near those will be the idle speed screw. By "blade" I assume you mean "chain". Can you tell exactly where the white smoke is coming from? Are you sure someone didn't put bar oil in the fuel tank?
LA - Idle screw to adjust butterfly position.
 
Can you tell us what you have done so far with adjustments? I'm not sure what you mean by LA. You should have one marked L and one marked H next to it. Near those will be the idle speed screw. By "blade" I assume you mean "chain". Can you tell exactly where the white smoke is coming from? Are you sure someone didn't put bar oil in the fuel tank?

i carried out the basic setting: screw the 2 adjusting screw down onto their seat (clockwise), then back off 1 complete turn (CCW).

for the idle screw (LA), I screw it counterclock wise until the chain stop running, and then a quarter turn in the same direction(ccw).

the problem is that if I do that (adjusting LA to make the chain stop running),the idle is rough and the chainsaw die).

i thought the smoke was coming from under the saw, but it is coming out the muffler
 
I wonder if it’s due to an air leak and it could be sucking in bar oil, though it does depend on the saw design, where is the smoke coming from?! Or have you accidentally put bar oil in the fuel tank?!

thanks for the reply. No, i didnt put bar oil in the fuel tank. I did my mix(engine oil and gas) in a jerry can and poured it in my chainsaw after.
The white is coming from the muffler.
Is it possible the problem is the gas itself? I used a gas tank I have at my cottage that was filled with 89 octane gas a couple months ago
 
thanks for the reply. No, i didnt put bar oil in the fuel tank. I did my mix(engine oil and gas) in a jerry can and poured it in my chainsaw after.
The white is coming from the muffler.
Is it possible the problem is the gas itself? I used a gas tank I have at my cottage that was filled with 89 octane gas a couple months ago
Yes change fuel, it’s quite possible it’s part of your problem, adjusting the carb is your other, also when did you last change your fuel filter? While there clean the air filter too.

We all know a couple month old gas is more than that haha. Mix up some fresh stuff.

As for tuning, unless you know what you’re doing, you won’t get it right and the manuals don’t help, they are a base line to start from. 1 turn out from lightly seated on L and H and turning LA to stop chain spinning isn’t tuned, it’s where you start. Take it to a shop for them to tune it.

There are some incredibly knowledgable and kind guys on here who will go out of their way to help you fix your saws, but learning any new skill takes time, dedication and patients. If you just want it to run and cut, the shop will save you a lot of time. Without a tach and guidance you could also blow the saw up fiddling with the screws.
 
Turn the idle speed screw in until you can keep the saw running, then adjust your low speed mixture screw for the fastest speed possible. Then turn it CCW a 1/8 turn. Then re-adjust the idle speed.
 
OP

I’m just now after a year, understanding tuning and that’s with guidance from a friend with a lifetime of experience.

It’s all good and well trying to follow a method, but the issue arises when the saw starts to do something you didn’t expect.

Say you go to 500rpm + spec, you find lean drop off and then richen it up, it may bog off idle still. Then what. Well you need to know if it’s a lean bog or rich bog. Does it splutter or dip? What do they sound like? You adjust incorrectly for one and then you are chasing your tail.

Then you need to know how and what to adjust to get it right. Then you go WOT, but if you don’t understand what 4 stroking is you really are asking for problems. Then you have a saw that wants to stall on return from idle but unless you know if it’s L or H you’ll chase your tail. Then your saw Starts to die at idle, so you increase idle, but what if your L is too lean or too rich and butterfly is not the issue. If you don’t know what to listen for it’s tricky.

Also, tuning with a saw that works as it should Is one thing, but what if you have an air leak, but you don’t know it. Tuning will go out the window and you’ll start chasing your tail again.

For the guys here who are experienced they will know, without thinking, what to do. What’s often forgotten is that an untrained ear doesn’t know anything.
 
Low speed tune issues are where a tach is really needed.

if you are at factory low rpm setting and the chain is still moving, the problem is in the clutch system and not the carb/saw itself. If you can’t get the saw down to near that spec without the saw stalling, you’ll need to check for a vacuum leak and then look into the carb.

Inspect the clutch and drum. Make certain you don’t have a broken spring or bad clutch bearing. If you have a tach, it’s makes it all much easier.
 
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