Stihl 034 Carb Adjustments

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Stihl Husqvarna

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So I was wondering if someone can help me with tuning my saw. I have a stihl 034. I'm trying to tune it but can't get it right. Do any of you have a 034 and if so how many turns on the H and L screws? Right now I have both set at 1-1/2 turns
 
Which carb do you have on your 034 and which version is your 034 exactly? I see you are from Canada and in this case you could have the C3A-S39B. That was used on canadian versions. For this carb the basic setting on H and L is 1 turn open from the closed position. But it is also possible that you have a other carb on it. In the 034, 036 family were a lot of different versions built that came with different carbs.

Maybe you can tell us which carb you have (it`s written or stamped on the carb body) and the serial number could also be helpful. There were a lot of changes in the 034, 036 family.
 
I have 27 of the 036 and 034 saws. The above post is right, for all the carbs of these models, even the arctic. Start at 1 full turn on low and high. One and a half turns would make it pretty fat, and the saw would fall on itself when pulling the throttle.

I typically don't see many adjustments past one and a quarter, unless I mm or I rebuilt the carb and there is still some stuff blocking a small port somewhere in the carb, and I either was half assed in cleaning it or it needs to run a little to get cycling right.

These saws are one of my favorites. Strong cases, light and good power. They run for a long long time when kept clean and tight.
 
More than likely

I'll be seeking some of them once I go over them top to bottom though,,, keep a look out
 
Saw tuning is more art than science. Start at 1 or 1.25 turns. Doesn't matter. Turn the idle screw until the butterfly just cracks a little. Start the saw and adjust the L screw in or out until it idles. Let the saw warm up a minute. Peg the throttle and turn the H screw until you get max rpms the richen until rpm's die down A LITTLE. Now your in the ballpark! I've noticed to get the H side right you need to cut some wood and adjust for max power.
 
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Which carb do you have on your 034 and which version is your 034 exactly? I see you are from Canada and in this case you could have the C3A-S39B. That was used on canadian versions. For this carb the basic setting on H and L is 1 turn open from the closed position. But it is also possible that you have a other carb on it. In the 034, 036 family were a lot of different versions built that came with different carbs.

Maybe you can tell us which carb you have (it`s written or stamped on the carb body) and the serial number could also be helpful. There were a lot of changes in the 034, 036 family.

I have a Zama carb couldn't really see any numbers though.
 
All the above advice is really good advice. I know I can't get a saw adjusted until it starts getting into the wood. I usually start with factory one turn on each, and yes, absolutely turn the idle up a little, like said, so it doesn't continually stall which happens sometimes. Get her warmed up, drop the idle until the chain stops spinning, or turn up until chain spins, then back off until it doesn't, assuming your clutch is in good working order.... then get a feel for how it walks off the low end. If it stumbles like it wants to stall before throttling up, from my experience it's a little fat on the low. If there's fuel spitting out the muffler or misting, or excessive smoke after a break in, too fat. Once the low end feels like it has good response and is sharp and quick, check the high end. Also, feel the saw for heat. Excessive heat, or warmer than what feels comfortable, is an indication of too lean. Cut with it for a little bit, and adjust as necessary, but just keep in mind that an 1/8 of a turn is a lot on these zamas and Walbros. I use a digital tach as well, wrapped on the spark plug. I love them. You can look in the manual and get factory idle and high r.p.m, and dial it if your saw is stock really fast.

With the 034 and 036, I have not had any saws I can recall that were past 1 1/4 on the turns, unless I m.m.

One thing I have seen more than once: make sure that pulse line is on. (They can slip off easy in these models)

Also, if it seems to stall excessively, take the pulse line off and check the plastic nipple on the tank side. I have had quite a few that had a hairline crack on that nipple, and it raises hell with em, and can even blow up a top end.

Sorry, for the long reply, I just love these models. My tree crews prefer the 036 over the newer saws for general cutting, limbing, etc.. for a mid range saw, they really are hard to beat. Light and powerful, strong and when tunes right they go all day without issue!
 
Make sure air filter is clean, have a sharp chain, and a piece of wood you can bury the bar in handy.

Try starting at 1 turn out on Hi and Lo. Turn idle so that it is in enough not to stall and out enough so the chain don't spin. Back out Lo until it stumbles (too rich) then back in until it starts to race (chain may spin, lean). Set Lo to halfway between rich and lean, you may have to adjust idle again at this point. Repeat low adjustment.

Hold briefly at WOT. If the saw does not "4-stroke"/burble, it is too lean, turn out Hi. If it burbles so much it won't rev it is too rich, turn Hi in. Once it revs at WOT but still burbles a bit, try it in some wood. If the burble does not go away it is too rich, turn Hi in, check in wood again. Check again out of wood that it still 4-strokes at WOT, if not turn Hi out.

Go back and check low and idle again, then repeat Hi adjustment. Depending on your "tuning ear" you may have to go back and forth to Lo and Hi several times to get it right.

If the saw stumbles as it transitions to full throttle, turn out/ritchen Lo a bit.
 
Sum-tin not right with that carb. That's a compensating MS series carb, not a 0 series carb.

The filter won't sit flush with the carb if it's an 034 filter. You'll have a leak. An MS air filter won't fit under the back cover.
 
Drf255 is right, the air filter needs to have the compensating part on the bottom for that to work right, and the air filter cover is larger to accommodate the size than the 034 was. Looks like it's an 036 tank, judging by the tank vent.

Also, to make the right adjustments, you need to take the locks off the high low needles.
 
Sum-tin not right with that carb. That's a compensating MS series carb, not a 0 series carb.

The filter won't sit flush with the carb if it's an 034 filter. You'll have a leak. An MS air filter won't fit under the back cover.


I agree with the compensating carb issue. I don't think those came out until the 036 pro. It may be a "Frankensaw", with 036/360 parts. Pictures of the tank, air filter and cover would help. There may also be part numbers on the parts that you can look up with an IPL to see what parts (034/036/360) you are working with. All the filter/cover/tank/carb parts need to be compatible and seal up.

You can take a carb w/compensating carb lower cover and switch with a w/non-compensating carb cover. Note that the compensating carb lower cover also has a grommet to mate with compensating carb air filter. You need all the carb/filter parts to mate up and seal properly before trying to tune things. Also if a compensating carb setup, take off lower carb cover to check for sawdust, if crap gets in there even with proper parts it won't run right.
 
Drf255 is right, the air filter needs to have the compensating part on the bottom for that to work right, and the air filter cover is larger to accommodate the size than the 034 was. Looks like it's an 036 tank, judging by the tank vent.

Also, to make the right adjustments, you need to take the locks off the high low needles.

The air filter does have a slot for the compensating hole on the carb?
 
I just wanted to see if you figured out your adjustment issues.... did ya get it?
 

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