# The official saw tuning thread.



## stihl 440 (Apr 5, 2007)

I think we need a official saw tuning thread. I need to know how to tune my saws. I haven't been able to get a straight answer out of my dealer or my manuals. I did a search, but I still can't understand it. Like I think the LS screw is idle, right? And the L screw is for the saw comming off idle, manual says to tune it so it accelerates smoothly. And the H screw is for the max high speed RPM, right? And how do you ear tune? Do you tune it until the saw is 4 stroking then back off some or what? I've hear all sorts of stuff and I don't know what to do. This might sound stupid but, I want to know how to tune.:help: This is the only thing that I don't know how to do on a saw. I think some of the :newbie: 's can use this thread also. I want to get a tach soon. I only know that my 440 and 460 are running at 13,900 because my dealer tuned them with a tach. :help::hmm3grin2orange: :biggrinbounce2:


----------



## 2000ssm6 (Apr 5, 2007)

I agree. Get a detailed report and sticky it at the top.


----------



## troutfisher (Apr 5, 2007)

Here's a link to Madsen's saw tuning page. There are audio files to help learning to tune by ear.



http://web.archive.org/web/20051228040631/www.madsens1.com/sawtune.htm


----------



## jack-the-ripper (Apr 5, 2007)

A tach is your best bet. I've tuned by ear but invested in a tach. It gives me piece of mind knowing exactly what RPM the saw is running, instead of "that's close". My saws are tuned to 200-300 RPM's beyond the manufacturers MAX. recommendation. Some people go as far as 500 beyond MAX.


----------



## Stihl_Learning (Apr 5, 2007)

After reading posts over the last few days, I ordered me a tach from my Stihl Dealer. It should be here tomorrow. 
Once I get it, I'm looking at a muffler mod and carb setting for my 036
John


----------



## rahtreelimbs (Apr 5, 2007)

I always tune *"by ear"* and then recheck with a tach. This also gives me an rpm to shoot for the next time the saw is worked on!!!


----------



## troutfisher (Apr 5, 2007)

jack-the-ripper said:


> A tach is your best bet. I've tuned by ear but invested in a tach. It gives me piece of mind knowing exactly what RPM the saw is running, instead of "that's close". My saws are tuned to 200-300 RPM's beyond the manufacturers MAX. recommendation. Some people go as far as 500 beyond MAX.



I agree, I always tend to de-tune a saw a bit by ear. I guess I'm just cautious. When I have a saw tuned on a tach It's usually set faster than I would by ear.


----------



## stihl 440 (Apr 5, 2007)

*wow!*



troutfisher said:


> Here's a link to Madsen's saw tuning page. There are audio files to help learning to tune by ear.
> 
> 
> 
> http://web.archive.org/web/20051228040631/www.madsens1.com/sawtune.htm



Wow troutfisher, that helped a lot! All the time I spent on madesens wedsite, I never saw that. But I could still use more info. :hmm3grin2orange:  :biggrinbounce2:


----------



## Lakeside53 (Apr 5, 2007)

rahtreelimbs said:


> I always tune *"by ear"* and then recheck with a tach. This also gives me an rpm to shoot for the next time the saw is worked on!!!



+1. 



LS (or LA) is just a throttle preset - nothing to do with mixture. L is the low speed mixture, and H is the high speed mixture.

After you are "in tune" with your saw, you won't need the tach, but it takes a while to train the ear. Some saws are very difficult to tune by ear - like a 361 - you don't ever get a "burble" - just a change of tone. Easier after a muffler mod though..


It's important to remember that the WOT methods are only a crude approximation of correct mixture. It will overstate the mixture on short bars (too rich - to keep RPM down) and understate (too lean) on very long bars (leaning out to get to max rpm). There is only one correct H speed mixture for a given set of environmental conditions.


The low end tuning is harder for some people than the H end - often because they are chasing weak clutch springs.


----------



## belgian (Apr 6, 2007)

Lakeside53 said:


> +1.
> 
> 
> 
> ...



Andy, I have a new sig for you : 

" Lakeside53 tells you how it really is " :rockn: 




> The low end tuning is harder for some people than the H end - often because they are chasing weak clutch springs



I tinker a lot on older generation saws lately and think that diagnosing and tuning the carb is the most difficult and time consuming part of the rebuilt. Low end tuning calls for some experience too, as you stated. Judging condition of membranes and their functioning is not easy also, while buying new sets is not always obvious for collector saws (they are not used for a living, hehe).
But I am getting better at it 


PS. just realize this is my 1000 th post on AS. Welp, I need a beer


----------



## blis (Apr 6, 2007)

belgian said:


> .......
> 
> PS. just realize this is my 1000 th post on AS. Welp, I need a beer



:rockn: almost there too...


----------



## Highclimber OR (Apr 6, 2007)

For all Stihls the manual tells you to turn them a certain number of times from completely closed. I think it is either 2and 1/2 or 1 and 1/2 and I go from there. You can do it by ear if you are familiar enough to do so. As long as you know which is open and closed, you should be all right. one is Idle, one is the Low, and one is the High. Usually the High needs very little adjustment, it's the Low that is a little touchy. Once you start fine tuning you will know when it is right, just make sure you have the saw running when you make the adjustments.


----------



## stihl 440 (Apr 6, 2007)

*tuning*



jack-the-ripper said:


> A tach is your best bet. I've tuned by ear but invested in a tach. It gives me piece of mind knowing exactly what RPM the saw is running, instead of "that's close". My saws are tuned to 200-300 RPM's beyond the manufacturers MAX. recommendation. Some people go as far as 500 beyond MAX.



I've alway's told my dealer to turn them 400-500 over max and never had a problem. But I started this tread because I want to start doing it myself. :greenchainsaw: :hmm3grin2orange:


----------



## Lakeside53 (Apr 6, 2007)

Stihl's spec'ed max wot rpm is +/- 1000 rpm, but that doesn't mean you should alays err on the high side. On a long bar that a recipie for lean seize.


----------



## royta (Apr 6, 2007)

Lakeside53 said:


> Stihl's spec'ed max wot rpm is +/- 1000 rpm, but that doesn't mean you should alays err on the high side. On a long bar that a recipie for lean seize.



I just briefly skimmed the web archive of Madsen's instructions, and he mentions setting max speed with bar & chain removed from saw. That should eliminate the problems of a lean sieze, shouldn't it? I guess that also means that once you put your bar & chain back on, no matter how short it is, the max speed will decrease from your setting.


----------



## Lakeside53 (Apr 6, 2007)

That way will pretty much guarantee you end up with an under performing saw (too rich). Stihl wants you to put the saw engine under some load, and that's why they spec "with bar and correctly tensioned chain".

I find it difficult to tune a saw correctly with the bar and chain removed.


----------



## Tzed250 (Apr 6, 2007)

Remember, its the mixture being adjusted, not the RPM. The RPM is a function of correct mixture, not the other way around. That is why the "ear" part is important (on saw that will let you do it).


----------



## royta (Apr 6, 2007)

Lakeside53 said:


> That way will pretty much guarantee you end up with an under performing saw (too rich). Stihl wants you to put the saw engine under some load, and that's why they spec "with bar and correctly tensioned chain".
> 
> I find it difficult to tune a saw correctly with the bar and chain removed.



You're right, I forgot about what it says in Stihl's manual.


----------



## stihl 440 (Apr 6, 2007)

*bar*



Lakeside53 said:


> Stihl's spec'ed max wot rpm is +/- 1000 rpm, but that doesn't mean you should alays err on the high side. On a long bar that a recipie for lean seize.



Ok, so my 440,460's running at 13,900 with a 20" bar is ok. I understand what you mean about the long bar rpms. So if a saw with a long bar(28" or so) on it is running 13,900, that would be the same as it running 14,500 with a 20" bar= lean seize on stock saw.


----------



## Lakeside53 (Apr 6, 2007)

28 isn't realy "long" for a 440. I'd say 20 is short, 32 is long and 25/28 are somewhere in the middle.

Best way to tune is to get it about right, then weak with timed cuts. Or, if you can't be bothered about he last few % and be worried about day to day changes, err solidly on the rich side and just cut wood.


----------



## ShoerFast (Apr 6, 2007)

Just .02 cents worth to finding that low-end sweet-spot.

As Andy mentioned, weak clutch-springs will toss this procedure out the window. 

It seems that a when a lot of people are having a bad idle day, the first thing they do is adjust the speed screw, or butterfly screw. The position of the throttle plate or butterfly valve, has a lot to do with how the saw will accelerate, if the plate has been advanced into the transfer slot for idle speed or to fix a stalling on deaccelaration , or compensating for a carb that needs a rebuild, they don't seem to accelerate as well, are sluggist and will not fallow the trigger as well.

After a carb rebuild, or to find that sweet spot again, let the saw warm up well, then let it idle for a minute or so on it's belly. Pick the saw up and roll it to one side or the other, even carefully flip it upside down, what your going to listen for is the saw stumbling rich with extra gas that has built up in the crank. There should be very little, or no change regardless of attitude. 

If the saw fails a roll-out test, try leaning the "L" screw, if this pick up speed, and the clutch engages and the chain creeps, back the speed screw out and repeat the roll out test. 

repeating this till your not getting any change rolling the saw after idling for a time, when you can get the chain to creep at will by leaning and riching the "L" screw, and a crisp acceleration, no stall at deaccelaration your there, never touch the speed screw again, unless your ready to repeat the roll out test again.

As we know that every saw is different, what I think happens with saws running on the transfer slot is the transfer slot is a very course/rich fuel for idle, and droplets fall out , build up, and cause stumbling problems. Getting that throttle valve just at the edge, or very slightly into the transfer slot gives a much smoother idle, and fastest trigger/acceleration.


----------



## stihl 440 (Apr 6, 2007)

*hardwood*



Lakeside53 said:


> 28 isn't realy "long" for a 440. I'd say 20 is short, 32 is long and 25/28 are somewhere in the middle.
> 
> Best way to tune is to get it about right, then weak with timed cuts. Or, if you can't be bothered about he last few % and be worried about day to day changes, err solidly on the rich side and just cut wood.



Just remember lakeside I'm on the east coast. We have all hardwood over here,(we have some softwood, but most of the time nobody wants to mess with it). We cut some pine, but that depends on how limby it is, if it is limby them we leave that for the guys with the timbco track harvesters not fellerbunchers. Because the guys with the fellerbunchers don't like it either, because they still have to limb it sometime. But we do sometimes get a pine stand that isn't too limby. The only softwood here that pays good is hemlock, and white pine. It is very rare over here to see over a 20" bar on a saw that is 440 size. Only the saws that are like, 660's size and over have 24" on them.


----------



## Haywire Haywood (Apr 6, 2007)

I have a question concerning tuning and elevation/atmospheric conditions. 

If a saw's sweet spot is 14k at 5000ft, will it still be in tune if readjusted to 14k at 1000ft. 

The point of my question I guess is this. I'm not much good at tuning. If at the GTG the guys tweak my saws just so, can I simply check the rpm with a tach and reset it to that when I'm cutting back home?

Ian


----------



## Freakingstang (Apr 6, 2007)

stihl 440 said:


> Just remember lakeside I'm on the east coast. We have all hardwood over here. It is very rare over here to see over a 20" bar on a saw that is 440 size. Only the saws that are like, 660's size and over have 24" on them.





Yup, Standard logger saw in this area are 460's with 20" and most 660's run a 20" too. Every once in a while there are 660's with 24", but 20" is bar far the norm. People look at me funny when i break out the 066 with a 36 incher...


----------



## rahtreelimbs (Apr 6, 2007)

Haywire Haywood said:


> I have a question concerning tuning and elevation/atmospheric conditions.
> 
> If a saw's sweet spot is 14k at 5000ft, will it still be in tune if readjusted to 14k at 1000ft.
> 
> ...




FWIW...........not that I am an authority on this...........at the GTG's that I have gone to I ran a modded 359 and 372. I turned them up to 14'600 rpm's just for the GTG and re-adjusted them back to 13'800 rpm's ( the sweet spot for work ) when I get back!!!


----------



## ShoerFast (Apr 6, 2007)

Haywire Haywood said:


> I have a question concerning tuning and elevation/atmospheric conditions.
> 
> If a saw's sweet spot is 14k at 5000ft, will it still be in tune if readjusted to 14k at 1000ft.
> 
> ...



Ian

My .02 cents here is no. 

The way I understand it is your setting the air : fuel ratio, optimal or sweet spot at 14K @ 5000' would be something lower at 1000' , not a lot, maybe 300 - 500 rpm's slower would be the same ratio.

An easy way to check that would be to check were the burble is at 5000' , for a say, say that is is at 13,500 , the sweet spot would be burble +500 rpm's, (burble , then lean 500rpm's) ,,, for the 2 cents, my bet would be that your 1000' burble would be at 13,000rpm's? (give or take)


----------



## Haywire Haywood (Apr 6, 2007)

That's my problem, I hear no burble, no 4 stroking. All I hear is WAAAAAAAAA when I hold the trigger down. Madsen's audio doesn't help either, it just sounds like a wide open chainsaw to me. Frustrating it is.

Ian


----------



## royta (Apr 6, 2007)

Haywire Haywood said:


> All I hear is WAAAAAAAAA when I hold the trigger down.



I put a transmission in mine. All I hear is WAAAAAAAAAAA WAAAAAAAAAAAA WAAAAAAAAAAAAAAA WAAAAAAAAAAAAAAA 

It's awesome.


----------



## ShoerFast (Apr 6, 2007)

Haywire Haywood said:


> That's my problem, I hear no burble, no 4 stroking. All I hear is WAAAAAAAAA when I hold the trigger down. Madsen's audio doesn't help either, it just sounds like a wide open chainsaw to me. Frustrating it is.
> 
> Ian




Yes, Tach time, starting at what, $20 bucks?

Back to your question, I live at about 6000" , but do a lot of cutting around the 9000" mark. At home setting my MS-660 at 13K just barely berbles out of the wood, but clears in the wood and is a good timed cut. Bring it to alititude, 9000' and it burbles at closer to 13,300 rpm's and clears in the wood.


----------



## Lakeside53 (Apr 6, 2007)

stihl 440 said:


> Just remember lakeside I'm on the east coast. We have all hardwood over here,(we have some softwood, but most of the time nobody wants to mess with it). We cut some pine, but that depends on how limby it is, if it is limby them we leave that for the guys with the timbco track harvesters not fellerbunchers. Because the guys with the fellerbunchers don't like it either, because they still have to limb it sometime. But we do sometimes get a pine stand that isn't too limby. The only softwood here that pays good is hemlock, and white pine. It is very rare over here to see over a 20" bar on a saw that is 440 size. Only the saws that are like, 660's size and over have 24" on them.



I know about your wood.. I'm taking about tuning.... WOT on a 440 with 20 inch will be rich at the max rpm allowed...


----------



## Lakeside53 (Apr 6, 2007)

Haywire Haywood said:


> That's my problem, I hear no burble, no 4 stroking. All I hear is WAAAAAAAAA when I hold the trigger down. Madsen's audio doesn't help either, it just sounds like a wide open chainsaw to me. Frustrating it is.
> 
> Ian



TACH


----------



## Lakeside53 (Apr 6, 2007)

Haywire Haywood said:


> I have a question concerning tuning and elevation/atmospheric conditions.
> 
> If a saw's sweet spot is 14k at 5000ft, will it still be in tune if readjusted to 14k at 1000ft.
> 
> ...



It will be close enough...


----------



## stihl 440 (Apr 6, 2007)

*rich?*



Lakeside53 said:


> I know about your wood.. I'm taking about tuning.... WOT on a 440 with 20 inch will be rich at the max rpm allowed...



So, you're saying a 440 with a 20" will be rich at 13,500? I run mine at 13,900. :biggrinbounce2:


----------



## Lakeside53 (Apr 6, 2007)

Yep... but it's o.k. if YOU control the max rpm... WOT is a lowsy way to tune, particularly on big saws with short bars.


----------



## ShoerFast (Apr 7, 2007)

Andy

Any tricks without a tach on a 361?

I did cut the metal or raised area around the 5/16 - 3/8th exit hole to give is a healthy 5/8" hole or so. 

Running that saw first time today was simply amazine, everything is a fast cut! But it seems a real trick to get anything better then ball park.

I have noticed that every bet of gas rich seems to give it an occasional jurk or berble, and keeps getting more burbely as you progress the "H" jet.

(interesting note, they were ready to send me out the door when I asked if I could see it on tach, just to get a feel for the tone brake, they were happy to,,,,, it was at 17K "H" against the rich stop!,,,,, we cut the stops off)


----------



## Haywire Haywood (Apr 7, 2007)

Lakeside53 said:


> TACH





Lakeside53 said:


> It will be close enough...



Good to know. I have the SenDEC STS-5000 tach that Bailey's sells. http://store.baileys-online.com/cgi-bin/baileys/1112?mv_session_id=KJF9QypE&product_sku=17122

Ian


----------



## Lakeside53 (Apr 7, 2007)

ShoerFast said:


> Andy
> 
> Any tricks without a tach on a 361?
> 
> ...




Nope... I'm useless tuning a stock muffler 361 without a tach. NO real burble at all.

Unless the muffler has been gutted on the inside, cutting the exit hole will have zero effect on the muffler output.. It's fed though a long tiny tube... unless you actually cut that tube away too, and that will negate your spark arrester. I add a second 16mm port and leave the factory port alone. Maybe I'm confused with what you did. 


I assume you looked at this thread showing the muffler internals?

http://arboristsite.com/showthread.php?t=33528


----------



## PWB (Apr 7, 2007)

So............. My 084 with 30" bar @ 12,500 that sounds too rich to me? (non rev limited coil) I'm chicken to go any faster.......... I'm at about 1000 feet.

Bought the stihl edt 8 a few months ago.


----------



## stihl 440 (Apr 7, 2007)

*12,500*



PWB said:


> So............. My 084 with 30" bar @ 12,500 that sounds too rich to me? (non rev limited coil) I'm chicken to go any faster.......... I'm at about 1000 feet.
> 
> Bought the stihl edt 8 a few months ago.



I think 12,500 is the stock max RECCOMENDED RPM for a 084. That saw isn't desined to turn RPMS but it is designed for torque, and long bars. I don't know of anybody tuning them higher, and I don't have one YET to tell you. But I think lakeside has messed with 084's before, he will probably know. :hmm3grin2orange: :greenchainsaw:


----------



## Gypo Logger (Apr 7, 2007)

I think carb adj. is where alot of people go wrong with a saw.
I know some local loggers who equate out of wood rpm with power, however, fuel requirements are alot different in the wood than out.
They were always going for max rpm out of the wood and wondered why they were losing bottom ends out of 088's and 066's.
Over the years I have developed my own method of carb adjustment.
Given that the carb has good diaphrams and the filtre is clean, I first turn up the idle speed screw (LA) till the chain begins to turn, then I turn in or out the L to get the highest idle rpm where the chain is turning the fastest, then I turn out the L about 5 minutes or so. If the saw then responds fast to full throttle I leave it there and turn out the LA till the chain just stops turning.
Then I go to the H and find the highest audible rpm and then richen it out about 5 minutes till it's not a flat out scream, but a slight burble.
This procedure I repeat at least two times till I get it right. Don't forget the 32:1.

John


----------



## 046 (Apr 7, 2007)

tune my carbs quite similar to gypo's method. 

1. low range is controlled by a combo of butterfly opening size and low speed mixture. 

2. high range screw only control high range. 

once you realize what controls what, adjusting is easy. 

always start H & L adjustment, from factory recommended settings. lightly bottom adjustment screws, then back out one turn, 3/4 turn or what ever mfg recommends. 

unscrew butterfly adjustment until completely closed. then screw in 1/2 turn open. start your low end mixture adjustment with butterfly just barely open. (if butterfly is opened too far, you cannot adjust low mixture properly)

start saw and blip throttle lightly... saw will want to die from butterfly almost closed. after warming up for 1-2 minutes. then open up butterfly screw just barely enough to get saw to idle. 

then adjust your L screw in or out until you find a peak at which saw runs at highest rpm. this will usually be within 1/2 turn of factory starting position. then go back and adjust idle to just below engaging clutch. 

if you cannot find a peak rpm point... something is wrong. either an air leak or a blocked L circuit. 

assuming you've successfully adjusted the low range. then you are ready to do H range. 

with bar/chain, air filter as you intend to operate. run saw wide open for a few seconds to see if saw blubs on high end. if you don't have a tach. objective is for saw to start blubb wide open. limiting rpm.

with a tach hooked up, adjust H screw to factory recommended settings. and you are done.... note instructions for H setting is for a stock saw. use gypo's instructions below for mod saws. 

leaner the setting, faster and more power saw will run. but higher risk of too lean and burning up piston. it's much safer to run saw slightly rich, then slightly lean. 

hope this helps to clarify adjusting your carb...



Gypo Logger said:


> I think carb adj. is where alot of people go wrong with a saw.
> I know some local loggers who equate out of wood rpm with power, however, fuel requirements are alot different in the wood than out.
> They were always going for max rpm out of the wood and wondered why they were losing bottom ends out of 088's and 066's.
> Over the years I have developed my own method of carb adjustment.
> ...


----------



## Haywire Haywood (Apr 7, 2007)

046 said:


> with a tach hooked up, adjust H screw to factory recommended settings. and you are done....



That's what I've been doing for the high end, but get the feeling that I'm not really "tuning" the saw because I've heard Andy and others say many times that every saw is different and what it's tuned at is +/- 1000 rpms from the factory spec for the high end. I'd hate to think I was running lean and risking disaster or rich and not getting all the potential power available to me.

I'll have to give your low end technique a try tho, I may have had my LA screw holding the butterfly too far open on the 346.

Ian


----------



## Lakeside53 (Apr 7, 2007)

046 said:


> tune my carbs quite similar to gypo's method.
> 
> .
> 
> ...




Good post 046, but...

Did you mean to say this? Setting L to peak will be way too lean on most saws, make for hard starting and poor acceleration.

Most saws, you'll find L peak then back it off about 1/4 turn i.e. firmly on the rich side, but still idling nicely, then adjust LA to compensate. Test for too rich by idling for a few minutes then tip the saw forward and see it it coughs out for stumbles badly -a sign of gas pooling. If so tweak L maybe a slight amount leaner and test for acceleration response.


----------



## Lakeside53 (Apr 7, 2007)

PWB said:


> So............. My 084 with 30" bar @ 12,500 that sounds too rich to me? (non rev limited coil) I'm chicken to go any faster.......... I'm at about 1000 feet.
> 
> Bought the stihl edt 8 a few months ago.




12,500 is max. I'd leave it just where it is... Max rpm is important on that big saw to allow for sufficient lube to the big end.


----------



## 046 (Apr 7, 2007)

opsss.. should have posted my instructions for H setting is for a stock saw. follow gypo's instructions above for a modded saw..




Haywire Haywood said:


> That's what I've been doing for the high end, but get the feeling that I'm not really "tuning" the saw because I've heard Andy and others say many times that every saw is different and what it's tuned at is +/- 1000 rpms from the factory spec for the high end. I'd hate to think I was running lean and risking disaster or rich and not getting all the potential power available to me.
> 
> I'll have to give your low end technique a try tho, I may have had my LA screw holding the butterfly too far open on the 346.
> 
> Ian


----------



## 046 (Apr 7, 2007)

thanks for pointing that out. usually end up richening up a but further to help response. mainly wanted to point out proper L adjustment is not possible with butterfly opened too far. 



Lakeside53 said:


> Good post 046, but...
> 
> Did you mean to say this? Setting L to peak will be way too lean on most saws, make for hard starting and poor acceleration.
> 
> Most saws, you'll find L peak then back it off about 1/4 turn i.e. firmly on the rich side, but still idling nicely, then adjust LA to compensate. Test for too rich by idling for a few minutes then tip the saw forward and see it it coughs out for stumbles badly -a sign of gas pooling. If so tweak L maybe a slight amount leaner and test for acceleration response.


----------



## Lakeside53 (Apr 7, 2007)

Yes, you can't tune with an excessive LA.

I normally reset the L to factory (say - 1 turn out), wind in the LA a good amount, start the saw, back off the LA until it idles reasonably, then check the L for range (plus/mnus 1/4 turn) and set it to a good but slightly rich idle, then LA again so the chain stop running. If it won't at a decent idle speed, change the clutch springs.

Why? I can't see or feel the LA engage the throttle or the postion of the butterfly on 99% of the saws I tune..


----------



## ShoerFast (Apr 7, 2007)

Lakeside53 said:


> Nope... I'm useless tuning a stock muffler 361 without a tach. NO real burble at all.
> 
> Unless the muffler has been gutted on the inside, cutting the exit hole will have zero effect on the muffler output.. It's fed though a long tiny tube... unless you actually cut that tube away too, and that will negate your spark arrester. I add a second 16mm port and leave the factory port alone. Maybe I'm confused with what you did.
> 
> ...



Thanks Andy

I need to go back in there, I widened existing hole, If there is any way that I can still use the factory spark arrestor, and free up some exhaust, it is so dry here much of the year. Understanding I may just have to add an extra port/screen.

If I can free up enough 361 exhaust, will the burble become evident?


----------



## Lakeside53 (Apr 7, 2007)

ShoerFast said:


> Thanks Andy
> 
> I need to go back in there, I widened existing hole, If there is any way that I can still use the factory spark arrestor, and free up some exhaust, it is so dry here much of the year. Understanding I may just have to add an extra port/screen.
> 
> If I can free up enough 361 exhaust, will the burble become evident?



Yes.. somewhat...


I'd leave the existing hole alone and add the aux hole like I did, with screen. There no real way to use the factory screen and make any material improvement in flow.


----------



## ShoerFast (Apr 7, 2007)

Lakeside53 said:


> Yes.. somewhat...
> 
> 
> I'd leave the existing hole alone and add the aux hole like I did, with screen. There no real way to use the factory screen and make any material improvement in flow.




I got it apart now*, Yes!

When I did it when I first got it home, I was going to cut the very next day and did something quick. Well it is still snowing and I have some 16mm chromed certified LMH tube (Lawn Mower Handle) . 

Thanks Again Andy, I saw the PN for the blower screen, it will be green here for another few weeks, but turns brown and crackly, scary with out a screen.

We all are deeply indebted to your dedication! 

* I have a horseshoeing tool that gets in there and pulls the creased-seam up very easily! I would not get one to just do mufflers, even if I did a lot of them. But something like this from a Flea Market would be worth tossing in a tool box.

This link has a close-up view of the tip: http://www.stcroixforge.com/products/handtools/nailpuller.html


----------



## stihl 440 (Apr 7, 2007)

*idle*



Gypo Logger said:


> I think carb adj. is where alot of people go wrong with a saw.
> I know some local loggers who equate out of wood rpm with power, however, fuel requirements are alot different in the wood than out.
> They were always going for max rpm out of the wood and wondered why they were losing bottom ends out of 088's and 066's.
> Over the years I have developed my own method of carb adjustment.
> ...



Gypo, I used your method of tuning the idle and I tuned the idle on my 280 because the chain was running at idle and it worked perfectly. She purrs like a kitten now, thanks. I'm still out of bullets for you .  :rockn: :hmm3grin2orange:


----------



## Haywire Haywood (Apr 7, 2007)

I got him for ya.

Ian


----------



## Dan Forsh (Apr 7, 2007)

Haywire Haywood said:


> That's my problem, I hear no burble, no 4 stroking. All I hear is WAAAAAAAAA when I hold the trigger down. Madsen's audio doesn't help either, it just sounds like a wide open chainsaw to me. Frustrating it is.
> 
> Ian



Yep, that's EXACTLY my sentiment. I bought a tach too.

But I'm going to keep reading this thread, the best one I've seen for a while.


----------



## stihl 440 (Apr 7, 2007)

*thanks.*



Haywire Haywood said:


> I got him for ya.
> 
> Ian



Thanks for getting him for me!


----------



## Haywire Haywood (Apr 7, 2007)

I re-tuned the low end just now and it's idling much better than before. I reset the jets to 1 turn out and started it, let it warm up (had to keep bumping the throttle to keep it running). I then turned the LA in till the chain would turn and with the tach clamped to the plug wire, adjusted the L till I got the highest rpm. I then richened it about 1/4-1/3 of a turn and reset the LA to about 3k. The chain stopped turning at about 3500 IIRC. We'll see how it starts cold. It restarted on the first pull but it was good and warm by then. 

High end?  I just made sure it was about 200 under factory spec. Better safe than sorry I suppose. Maybe the GTG can edumacate this :monkey: on burble.

Ian


----------



## Stihl_Learning (Apr 7, 2007)

Dan Forsh said:


> Yep, that's EXACTLY my sentiment. I bought a tach too.
> 
> But I'm going to keep reading this thread, the best one I've seen for a while.



my tach didn't come in Friday  
but should be here monday

I liked the thread so well I copied and pasted it into Word so I could print it out as a reference guide to keep with the Tach  

but now I gotta keep watchin it for changes opcorn: opcorn: opcorn: 
John


----------



## PA Plumber (Apr 7, 2007)

Good Thread.

Is the one turn out for "L" and "H" pretty commom across the board for Stihl saws? What about the "LA" screw? Is the factory "LA" adjustment also one turn out?


----------



## Haywire Haywood (Apr 7, 2007)

The workshop manual told me what the initial settings for the H and L were, but didn't mention a standard setting for the LA (it's actually "T" on my Husky).

Ian


----------



## PA Plumber (Apr 7, 2007)

Haywire Haywood said:


> The workshop manual told me what the initial settings for the H and L were, but didn't mention a standard setting for the LA (it's actually "T" on my Husky).
> 
> Ian



It's "T" on my small Echo also. "LA" on the Stihl.


----------



## ShoerFast (Apr 7, 2007)

*Ms-361*

The 361 seems an odd duck to me. My ear just dose not tell me what I would like to know.

Factory new, they want it to do it's dirty work via a 9MM hole in the internal exhaust plumbing. That dog wont hunt for me, so in the existing exhaust outlet area, I welded a tube with an 5/8" ID . (Andy, I really like your 361 muff mod, but would like to keep the smoke a little further from the wood and punk-bark here) 

With a 5/8 tube for an exit , to me, the 361 still dose not seem to have a good burble when set too rich, so I did some timed cuts.

Starting way fat , you could tell that it just did not even seem like it could get out of it's own way.

1 1/4 turns out from all the way in, cutting a 16" Douglas Fir.....

1 1/4 @ 18 mississippi's 

1 1/16 @ 16 mississippi's

1 1\16 @ 14 mississippi's

1 turn out, seemed a good 12 mississippi's and a nice transition from free speed into the cut .

At 7/8 and 3/4 turn out , it seemed that there was way too much "Whhhhhhhhh" and fell on its face in the cut, didn't complete the cut, but it would not have made the half way point in 8 mississippi's, and you could tell that it was slower cutting then even the 1 1/4 turns out.


----------



## Lakeside53 (Apr 7, 2007)

Haywire Haywood said:


> The workshop manual told me what the initial settings for the H and L were, but didn't mention a standard setting for the LA (it's actually "T" on my Husky).
> 
> Ian



There is no initial setting for LA - just turn it in until it just pushes the throttle plate open a tad or, if you can't see it, turn it way in, start, then turn it out until it just idles, than L, then LA again ..etc,,


----------



## 046 (Apr 8, 2007)

I tried explaining how it's done here. http://www.arboristsite.com/showpost.php?p=639145&postcount=41

it's important to adjust L screw with throttle plate (butterfly) opened small as possible. 

if you can see the throttle plate, it's easier tell where you are at. start at 1/2 turn open. if you can't see throttle plate. back off screw until no resistance is felt. then carefully screw in 1/2 turn past point resistance starts. 

start engine, run engine 1-2 minutes to warm up, then turn screw to open throttle plate, just enough to keep running. 

then find peak for L screw. then test for throttle response. slightly richen 1/4 turn or lean as per lake's instructions.


----------



## royta (Apr 12, 2007)

*tuning on the 044*

I have an 044, s/n 139xxxxxx, and it has the 3/8" rear hole in the muffler. How much burble will I get when tuning? Will it be obvious when I have the H set correctly?


----------



## Lakeside53 (Apr 12, 2007)

Yes and no... use a tach until you are "in tune" with your saw.. and get rid of the that 3/8 hole..


----------



## troutfisher (Oct 2, 2007)

Bump...

s'more good Lakeside info.


----------



## troutfisher (Oct 19, 2007)

troutfisher said:


> Here's a link to Madsen's saw tuning page. There are audio files to help learning to tune by ear.
> 
> 
> 
> http://web.archive.org/web/20051228040631/www.madsens1.com/sawtune.htm



This link doesn't work anymore, anyone have a link to Madsen's saw tuning page (archive)??


----------



## ray benson (Oct 19, 2007)

Try this page.
http://web.archive.org/web/20041225121212/www.madsens1.com/sawtune.htm


----------



## troutfisher (Oct 19, 2007)

ray benson said:


> Try this page.
> http://web.archive.org/web/20041225121212/www.madsens1.com/sawtune.htm



That's what I was looking for, Thank you. rep on the way.


----------



## geofore (Oct 30, 2007)

*carb tuning*

I'm working on one today and here is where to find a few secrets about walbro carbs that work for saws also.
http://tech.flygsw.org then click on engines and stuff then click on gas carb tech then click on how to tune a walbro. Now when you're at a GTG and the guy tells you his diaphram is blue because it's off a Makitia, you'll know he's pulling your leg and his time in the cut is going to leave you eating sawdust.


----------



## Haywire Haywood (Oct 30, 2007)

Southwest Aero Modelers said:


> Go to full throttle. Adjust the top end needle for peak RPM. Leave it wide open for about a minute to see if it changes any.



Ouch.. I don't think I'm going to lean my saw out for peak RPM and then hold it WOT for a full minute. 

You gotta keep in mind that these airplane engines have props on them, so they are under constant load the whole time they are running. It's akin to tuning a chainsaw in the cut but with a more consistent load applied. If you could put a load on a saw like that it would work well I expect.

Anyone want to hook their saw up to a ceiling fan and let us know how it turns out?  

Ian


----------



## diesel&coffee (Feb 26, 2009)

:bang:


----------



## harrygrey382 (Feb 28, 2009)

OK, so this is dragging up an old thread - bash me if you think I need it...



Lakeside53 said:


> It's important to remember that the WOT methods are only a crude approximation of correct mixture. It will overstate the mixture on short bars (too rich - to keep RPM down) and understate (too lean) on very long bars (leaning out to get to max rpm). There is only one correct H speed mixture for a given set of environmental conditions.


Given the last statement - That'd mean going on the WOT tuning, you'd need to chose a medium saized bar for the saw, then do your tuning, then leave it at that whatever the bar size? 

Assuming you're not going to WOT it out of the wood with a short bar the whole time... But will it also be gutless with a longer bar? Will it be running too lean tuning with a very long bar?


----------



## diesel&coffee (Feb 28, 2009)

:notrolls2:

what scotch u been drinkin today?? :biggrinbounce2:


----------



## cherrycutter (Feb 28, 2009)

I have the sts 5000 tach from baileys. At 13k my 660 is burbling alot. with 
25" bar. Does that mean it's safe to take it higher. Same with my 441 at 
13.5k. I am running 100 LL av gas, does that have anything to do with it. 441 seems ALOT louder than the 660. Both have stock mufflers until I get my dp for the 660 tomorrow.


----------



## windthrown (May 18, 2009)

Re-dragging up a great saw tuning thread. Gypo, Lake, all the old guard that are gone now. *Sniff*


----------



## nmurph (May 18, 2009)

andy is gone???? did i miss something?


----------



## tdi-rick (May 18, 2009)

nmurph said:


> andy is gone???? did i miss something?



http://www.arboristsite.com/showthread.php?t=98090


----------



## nmurph (May 18, 2009)

ok. i thought he and muley were abducted by aliens.


----------



## windthrown (May 18, 2009)

No, Lakeside Andy is retired from AS at 25,000 posts. He was burned out. 

Gypo was banned at his own request. Also burned out.


----------



## edisto (May 18, 2009)

nmurph said:


> ok. i thought he and muley were abducted by aliens.



I thought muley was an alien.


----------



## windthrown (May 23, 2009)

Muley_ IS _ an alien...


----------



## Sc0 (May 26, 2009)

bump, tired of searching for this thread...

Tuning a Dolmar 3410TH, turning about 2900 at idle and chain is not moving, then burning rich at 11850 at top speed. Still breaking it in on the rich side then will retune it again and lean it out a bit after a few tanks. (factory settings were 3200rpm at idle and 13800 top speed) From a cold start the choke is on, kinda cranks over on first pull then take it off of choke and after another pull it fires right up. Felled and debranched a 10" oak, it's definately not a 7900 but the fuel lasts longer and is much lighter... First tophandle in the inventory.


----------



## splitpost (Aug 1, 2010)

Sc0 said:


> bump, tired of searching for this thread...



Me too


----------



## roncoinc (Aug 1, 2010)

Wow,,dig up a three year old thread ??
let it die.
just ask questions..


----------



## logbutcher (Aug 2, 2010)

stihl 440 said:


> Just remember lakeside I'm on the east coast. We have all hardwood over here,(we have some softwood, but most of the time nobody wants to mess with it). We cut some pine, but that depends on how limby it is, if it is limby them we leave that for the guys with the timbco track harvesters not fellerbunchers. Because the guys with the fellerbunchers don't like it either, because they still have to limb it sometime. But we do sometimes get a pine stand that isn't too limby. The only softwood here that pays good is hemlock, and white pine. It is very rare over here to see over a 20" bar on a saw that is 440 size. Only the saws that are like, 660's size and over have 24" on them.



Just reviewing some fine old posts on tuning...excellent info. Thanks !

BUTT: here in Maine the major harvesting was, until this economic shutdown,
pulpwood. Most of the pulp logs are spruce/fir, in 4' or tree length depending on the mill and logger. Us "*homeowners*" (  ) with low tech gear sell in easier to manage 4' lengths. 

Out of country trekking northern Norway ( have not seen Sawtroll....yet ).


----------



## edisto (Aug 2, 2010)

splitpost said:


> Me too



There's a link to this thread in the chainsaw FAQ 'sticky'.


----------



## Rprecision (Nov 27, 2010)

On my Stihl 028, 

Set the idle till it starts to spin chain, set the mix on L to highist +1/4 rich (out) 

Set the proper idle speed 

Set the H for the highist RPM by sound + 1/4 rich (out) 

This is at 10,000 - 12,500 '


----------



## woodfar (Feb 12, 2011)

*carb tune*

I have a Stihl 026 that will not start. Picked it up used. It started and ran fine for about a half tank of fuel and shut off. It has spark, fresh fuel, and compression. What is the initial adjustment screw settings for this saw?


----------



## PappaWheelie (Mar 15, 2011)

troutfisher said:


> Here's a link to Madsen's saw tuning page. There are audio files to help learning to tune by ear.
> 
> 
> 
> http://web.archive.org/web/20051228040631/www.madsens1.com/sawtune.htm


 
There was an error when I tried the site. Is there another address?


----------



## Adam_MA (Mar 16, 2011)

Try this one

Saw Carb Tuning

Also, check these links for some of saw tuning videos

http://arboristsite.com/chainsaw/111707-10.htm#post1860951

http://www.arboristsite.com/chainsaw/113538.htm


----------



## MNfarmer (Dec 5, 2012)

So how much 4 stroke is best?? Do you want it where it barely cleans up in the cut or where you can barely here the 4 stroke when you let up in the cut?


----------

