• Please be aware that we have recently gotten a wave of users that, when researched, are found to be from Nigeria. They are trying to sell products and asking to be paid through Zelle or Venmo leaving users with no recourse if they don't ship the product. If you suspect this activity please contact admin and we will research their information to verify their location.

ArboristSite.com Sponsors
Peak Industries


Video: How to tune a chainsaw

blsnelling

blsnelling

Retired Hack
Joined
Nov 8, 2006
Messages
53,688
Age
51
Location
Franklin, OH
There's more to tuning a chainsaw than just adjusting the high end, but this is a start. It also gives an excellent example of what 4-stroking sounds like.

In the first cut, the saw continues to 4-stroke, even towards the bottom of the cut. That's a little too rich. It should run clean all the way through the cut once under load.

After that first cut, I tune the H screw. I turn the H screw in clockwise until the engine peaks out and is totally 2-stroking. No 4-stroke at all. I then quickly richen the mixture back up by turning the H needle counter-clockwise. Immediately you hear the engine begine 4-stroking again.

The next cut you can hear the engine immediately clean out once underload, and stay that way for the entire cut. After that cut I rev the saw and you can hear that it is still 4-stroking at WOT. It's important to check for that after a cut, since that's when your saw will be its hottest and leanest.




I'll try to make a more detailed tuning how-to video that includes L and LA adjustments.
 
Last edited:
blsnelling

blsnelling

Retired Hack
Joined
Nov 8, 2006
Messages
53,688
Age
51
Location
Franklin, OH
So how do you tune the H on your rev limited saws? Well, it's really not all that much different. As I mentioned you can hear it continuing to 4-stroke through out the first cut. Since you can't tune at WOT on a rev limited saw, just go ahead and turn the H needle in clockwise maybe 1/16 of a turn. I'm talking a very small amount. When you're close to right, a very small adjustment can make a huge difference. Then make another cut. If it's still 4-stroking in the cut, give it another small adjustment clockwise. Do this until the saw runs cleanly through out the cut.
 
TRI955

TRI955

I'm the man in the box
Joined
Jul 30, 2008
Messages
3,623
Location
Highland, IL
There's more to tuning a chainsaw than just adjusting the high end, but this is a start. It also gives an excellent example of what 4-stroking sounds like.

In the first cut, the saw continues to 4-stroke, even towards the bottom of the cut. That's a little too rich. It should run clean all the way through the cut once under load.

After that first cut, I tune the H screw. I turn the H screw in clockwise until the engine peaks out and is totally 2-stroking. No 4-stroke at all. I then quickly richen the mixture back up by turning the H needle counter-clockwise. Immediately you hear the engine begine 4-stroking again.

The next cut you can hear the engine immediately clean out once underload, and stay that way for the entire cut. After that cut I rev the saw and you can hear that it is still 4-stroking at WOT. It's important to check for that after a cut, since that's when your saw will be its hottest and leanest.

<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/5BZkB9QQTJU&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/5BZkB9QQTJU&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>



I'll try to make a more detailed tuning how-to video that includes L and LA adjustments.
If I've seen you do it once, I'd swear I've seen you do it a hundred times!!!!:laugh::laugh: Good post again Brad!!!

:cheers:
Mike
 
TraditionalTool

TraditionalTool

Addicted to ArboristSite
Joined
May 1, 2009
Messages
1,983
Location
somewhere
That is pretty good, but your capable of a much better video Brad. Not to be the bad apple, just that it is one simple H tuning in the video.

Would be nice to see a video that explains exactly what you describe, so that it doesn't leave any guessing for folks.

Rather than a sticky, I'd rather see a forum where tutorials could be posted, and keep them all together.
 
blsnelling

blsnelling

Retired Hack
Joined
Nov 8, 2006
Messages
53,688
Age
51
Location
Franklin, OH
That is pretty good, but your capable of a much better video Brad. Not to be the bad apple, just that it is one simple H tuning in the video.

Would be nice to see a video that explains exactly what you describe, so that it doesn't leave any guessing for folks.

Rather than a sticky, I'd rather see a forum where tutorials could be posted, and keep them all together.
I stated as much in the first post. I may actually be able to do that tonight.
 
StihlyinEly

StihlyinEly

Addicted to ArboristSite
Joined
Oct 6, 2009
Messages
3,967
Location
Ely, Minn.
Website
www.stevefossimages.com
That is pretty good, but your capable of a much better video Brad. Not to be the bad apple, just that it is one simple H tuning in the video.

Would be nice to see a video that explains exactly what you describe, so that it doesn't leave any guessing for folks.

Rather than a sticky, I'd rather see a forum where tutorials could be posted, and keep them all together.
Now that's an even better idea! :clap:

If Brad's crank seal/pressure/vac tutorial is anything to go by, I'm sure the more formal tuning vid, when it comes, will be informative and complete.
 
Kansas

Kansas

ArboristSite Guru
Joined
Jan 17, 2008
Messages
815
Location
Kansas
Thank you sir!

Hearing that makes me feel better thats pretty much how Ive been adjusting my saws too. I didnt know if it was right or not but I do what sounds crisp and clean under a load on the h screw and quick accel with no stumble on the low screw. :cheers:

Kansas
 
dingeryote

dingeryote

Blueberry Baron
Joined
Nov 21, 2008
Messages
13,604
Location
Michigan
Good job on the tutorial Brad!!

I have been tinkering with the 372 post Muffler mod. and my ears have gotten lean scream paranoid LOL!!

Just can't seem to find and keep a light 4 stroke that is "Comfy" LOL!!!

Somebody elses reference is good for the nerves!:cheers:

Thanks!
Dingeryote
 
TraditionalTool

TraditionalTool

Addicted to ArboristSite
Joined
May 1, 2009
Messages
1,983
Location
somewhere
I stated as much in the first post. I may actually be able to do that tonight.
That would be nice, I'll watch for it, not holding you to tonight.

This was good, don't get me wrong Brad, just sayin'...in follow up to what you were sayin'...(and yes, I noted you made comment to that effect;)).
 
Top