Got my Walker's Mufflers!!!

Hey everyone jsut a quick update-

Got my modded mufflers for my 360 and 460 this weekend. Put em' on Sunday afternoon and woah! Man do these things run differently!!!

I had to practically do a complete re-tune on the LA and L screws.
When I started them up the chain was turning on both so I had to basically turn the LA screw down almost all the way and then tweak the L screw to adjust the idle on each. Also on the 460, I have the H screw just about ALL the way richened up and I am still just about tachn' out at the max 13,500 rpm!!! And in the cut, the 460 can't be stopped, no way to bog it down and it just pulled itself right through the wood!!! MAJOR power upgrades!!!

I still have some fussin to do with the 360 sometime soon, I spent most of my afternoon yesterday messing with the 460 tuning. They both idle really different now and faster than before as well as produce more power now than stock.

I do notice on the 460 that if you are idling for a while and just tap the throttle really quickly about 1/4-1/2 the way in, it kinda jumps and then rpms drop down some and come up again. It is a stupid observation b/c there is no point in doing that to the saw, if you are going to give it a few quick revs, there is no problem with that. I notice it when I was setting the low end, let it idle for a while, gave the throttle a very light quick tap and she choughed an died. I think I just leaned the low end up a touch and its purrin now!
Next is to tune to perfection the 360!!!

-Drew

Lets revisit the above post-

At lunch I went home and played with the 460, no cuts just wanted to revisit my carb settings.

Well I was able to turn the LA screw in more to increase idle which may have accounted for it "choking" when slightly tapping the throttle, and richend up the low end setting to about 1/2 way. Good accleration, it comes down off of throttle nice and smooth, and idles great.

I then picked up my digital tach and went for a quick top end reading leaving the H screw richened up almost all the way and pulled a 12,620 rpm or there abouts.

With that top end reading, the saw seems to be responding the way it did before the new muffler was installed. I will eventually lean out the H screw as it is to rich right now.

Its funny though, I left both saws sitting for about 2 weeks or so with no gas in them waiting for my new mufflers. When I installed the mufflers and filled em up, it started and was idling so fast the chain was moving, not creeping, but moving so I started fiddling with the carb settings a la LA turned all the way down and haveing to "completly re-do the LA and L carb settings", which in turn totally messed up my H setting making it run leaner than if it had been set correctly. I am assuming that as I started the engine it was running lean due to the saw being run for the first time with gas in a while, and if I had let it alone would have probably gone back to normal once she had burned some mix for a bit longer.

So I guess all 3 screw settings are to some degree dependant on each others position. Learn something new every day!!! I guess this will make tuning the other one easier!!!

Sorry for the ramble-

Drew

Rocky-

I actually printed that page out and have it in my garage! Yes I do try to follow their procedure. In fact I have printed just about every page on that site that has information / instructions and have it all in a binder for reference. Think I have the low end tuned correctly now, of course I thought that the first tim too.

When you all set idle speed do you set the LA just underneath the point of chain movement, or do you tach it to the manuf. RPM listing in the owners manual?

I figure you start at the LA, set it right
Set the L screw accordingly
Set the H...
Then rechcek LA for no spin and the L setting at idle and accleration.

-Drew

99% of us dont use tachs.
Set the idle and L screw so the chain doesnt move and there is no hesitation when you gun it
Set the Hi speed so the saw has balls in the cut and has a slight four stroke sound when revving freely.

Thats it. You are making it much more complicated than necessary, but I think you are getting the hang of it. Now quit agonizing over 25 rpms and just enjoy the dang thing

drew i think hes rite. everyone of my saws had to be readjusted after i opened them up some. i just assumed the air fuel mix was leaner due to the engine getting more air and the gas staying the same. the only advice i feel qualified to give ,,is make sure u dont just creat a saw that will turn amillion rpm. try to get the rpm as high as it will go ,,and still cut with power . always keeping in mind that to lean ,,is just not a good thing . i know that for sure ,,
i tried to make a saw that i had run like dans 372 that i may get someday.
picked it up one day and there was no sign of rings ,,left. funny thing is i thot it was perfect when i parked it that day. not.
please let me know after a while just how much the new muffler helped u saw.
fact is what im looking for ,,so
also let me know privately ,if it dont think it really helped much.

drew,
i think you will be very, very happy with your walkerized muff.
once again i am on the pc and the numbers are in the shop. i had an owesome change in power when i tested them. some one else did the numbers and i think the increase was around 25%. i will do some digging the next few days and repost the findings. marty

CARB AJUSTMENTS

He needs to own a muckaluck after the firt week his right arm will look like a reg screw driver.

Re: CARB AJUSTMENTS

Originally posted by rooster71
He needs to own a muckaluck after the firt week his right arm will look like a reg screw driver.

Click to expand...

Amen

primate

I must admit i still wouldnt use any thing else. my right arm drags on the ground and my index fingure says snap on . lol

HEY! How come noone else stepped in and prodded Drew when he said he sets the LA screw first then sets the L screw after that? How does that technique give him a proper mixture? All that does is make the saw idle at factory spec. Who cares if it idles at spec if performance sucks or vice versa. You have to back the manual idle screw out until it has no effect on the engine, then set the Lo screw. When you are happy with the Lo speed then you can turn the idle screw in until it brings engine rpm into range. Now do the Hi screw then check off idle performance and starting. Adjust the Lo screw and idle screw as needed. If you needed anything more than a minor tweak to the L needle you`d better check the H needle again.

Russ

now see there ... we done learned something else [or i should say i did].
thanks russ. i think ive been doing it that way ,,but never really thot why. now i know.it just worked the way u described ,didnt work without .
again,, proofs in the pudding[or how the saw runs an cuts ] in this instance.

Thanks for all the replys everyone.

Jokers, what do you mean "back the manual idle screw out until it has no effect on the engine" ? What would be "no effect on the engine". I always thought you turned the idle up till the chain started to move, then backed it off till it dosent. Set the L for good accleration and then the H then check the L screw again? That is per the Madsens web page, and thought that was the appropriate way to set up a saw, no???

Tony-
I will let you know what I think once I get these saws set up and make some cuts.

Rooster-
What in the world is a 'muckaluck' ?

Drew if you have a tach the best way to set the carb is to leave the idle screw in the factory postion. Adjust the ls screw leaner till the saw shuts down, then turn it back richer till it start and idles perfect. Next tach the HS to 13,500. makes some cuts and note how the saw feels. Fine tunethe hs screw until you find the rpom that cuts fastest. Once you find the ideal rpm right the number inside your filter cover so you can tune the saw perfect everyday. FWIW the audible method as outlined on madsens website sucks. In most cases you wind up with a saw that is much too rich. The tach method is easier and is repeatable.

Thanks Bwalker-

First a question. How do I accomplish setting the LA screw back to factory spec???

Second, I agree with you about the tach. I tried the 'by ear' method and didnt care for it. If you crank it up with a tach, get the correct rpm and still hear some 'blurble' you should be ok. I know everyone out there has different opinions on this but it makes a lot of sense to me this way.

Thanks for the help-
Drew

Well Fellas, I can`t teach you reading comprehension, and Madsen`s site, while great in many ways, is a prime example of just enough info to be dangerous. I just went and checked their site to be on the same page as you guys who are relying on it and it was quickly apparent to me that they are assuming your Lo screw is adjusted properly. Reread what they have posted. The second step in the process, actually listed as step (6) is the correct first step, but it still doesn`t tell you to back off the LA screw which is no different than holding the throttle partially open so you may not even be fully on the idle circuit. When you have completed step (6), proceed to reading step (7) before you continue. Here, I`ll make it easier: "(7) Go back to step (5) and reset the idle speed. Chances are that the RPM setting has changed since you
optimized the fuel mixture adjustment." I`ve said it before and I`ll say it again, tachs are primarily a crutch for the inept. They get you in the ball park but they don`t tune your engine.

Russ

Well looks like I am going to adopt the "if its running well, idling well, and acclerating well,..... leave it be. This shouldnt be rocket science, but it sure is starting to feel like it. If it dosent bog or is sluggish to acclerate, and the saw dosent die when left to idle for a spell, its set just fine on the low end.

As it sits now, the saw just feels right. Got hell for power when you snap that trigger, and I just need to tweak the Hi end a touch leaner.
So I will do that and get back to the thing I love about these saws, cuttin wood!!!
Thanks to everyone for their help, you all are great!
-Drew

Not that anyone cares at this point, but to give this particular thread some closure I went home and analyized the 460 settings.

Turns out that the LA screw is at the factory setting per the picture in my owners manual and the L setting is just about down the middle.

It purrs like a Jaguar when at idle and screams to 13,300 RPM's like a Ferrari. It is a lean mean wood cutting machine.
Now if I could just figure out how to sharpen a chain worth a ???? i'd be all set!!!

Thanks again to all who commented

This thread is dead,

Drew

Drew, The idle screw does nothing except advcance the throttle a bit, so it does rerally effect tuning. To clarify what i said above. You want the LS as lean as possible and still have idle ability without advancing the idle screw too far. Then tach your HS to the factory spec and test for cut speed form there.

As far as naysayer of the tach as a tuning tool. I guess everyone has their own oppinion, but the ear is a very un precise instrument and as such doesnt provide for very consistant tuning.

well for an old hayseed like me. the only thing im looking for is power [in cut]..
to me its the test that matters to my back. with of course the one reservation.... i dont ever feel comfortable with the h side less than one full turn out. its a personal thing..

"The idle screw does nothing except advcance the throttle a bit, so it does rerally effect tuning."

So are you saying it does or doesnt effect tuning that much?
I have the LA set to look like the picture in my owners manual where the slot is just off vertical to the right at an angle.

Just curious is all...

Drew