New guy with questions (Stihl 290 Farm Boss)

[TLSF150]

Hey guys new to the site here.. I picked up a nice little MS290 off CL last week for $175 which I think was a pretty good deal.. This is my first saw but ive been working for tree services for a little over a year as a groundsman so im not a complete new guy when it comes to running saws but no expert either.. Anyway I took the 290 to work with me Thursday and Friday and it really surprised me how well it did.. it kept up with the 310s at work pretty well keep in mind my 290 was running a 18 inch bar and the 310s have 20s

Heres the saw

But of course after reading a couple threads here I came across this Muffler Mod thats suppose to really wake this saw up.. And being the type of guy I am I jumped on it lol..

So heres my question.. I know I have to re tune the saw now.. I already removed the limiter caps from the needles but Where should I put the needles without the caps for a baseline to start tuning?

 

[H 2 H]

One turn out on each screw from when it seated is a starting point

Welcome to the Jungle :msp_wink:

 

[TLSF150]

Thanks for the response.. hows my muffler mod look?? I keep thinking maybe I didnt open it up enough but dont want to go to much either

 

[H 2 H]

You'll be fine

 

[moody]

Thanks for the response.. hows my muffler mod look?? I keep thinking maybe I didnt open it up enough but dont want to go to much either

It'll do fine. Welcome to AS don't listen to us here and you'll live a happier life with your 290. Nice to see you didn't at least pay $300 for the saw like I see them priced for:msp_biggrin:.

 

[SawTroll]

:taped:

 

[struggle]

:taped:

You always love some fresh 290 love

 

[struggle]

Thanks for the response.. hows my muffler mod look?? I keep thinking maybe I didnt open it up enough but dont want to go to much either

I was going to say you went to far on the MM but if it works well as it is I would leave it. In the past i never opened up the muffler quite that much on the 290

 

[TLSF150]

I actually dont know how it runs with the muffler mod... I just cut it tonight and planned on tuning it tomorrow.. If its to much I could always close off the bottom port..

 

[Saw Dr.]

Thanks for the response.. hows my muffler mod look?? I keep thinking maybe I didnt open it up enough but dont want to go to much either

It looks VERY loud. I have modded at least a few (dozen) 1127 mufflers. I have never gone that far with one either, but I always try to make mine a little more user friendly. No worries, if it is too much, the mufflers are cheap. I would start out with the needles 1.5 turns out (too rich) and work them in to the correct setting. Read up on carb tuning and ask questions. If it runs too lean for long, it WILL score the top end. I have a whole bucket of scored 290 pistons here to prove it plus three complete saws that I have not torn down yet.

Some of the resident "experts" will make fun of your 290. Ignoring them will serve you well. Welcome aboard.

 

[TLSF150]

You think closing the bottom port would help any? And thanks for the heads up but I dont care who hates on my saw lol.. I bought it because I wanted to own my own saw not because I needed it.. at work we have a whole room full of saws for anything I could possibly need I just wanted the sastisfaction of actually owning my own..

 

[procarbine2k1]

Those are fine running saws, even in stock form. They do respond well to a muffler modification, and as Saw Dr. said- if it turns out to be a little loud for you, mufflers are pretty cheap.

 

[7sleeper]

You think closing the bottom port would help any? And thanks for the heads up but I dont care who hates on my saw lol.. I bought it because I wanted to own my own saw not because I needed it.. at work we have a whole room full of saws for anything I could possibly need I just wanted the sastisfaction of actually owning my own..

Congratulation! Sounds like you did the right thing. If your not happy with the performance you can always transform it into a sleeper saw.
:chainsawguy:
Just put in a 390 topend and don't tell anyone! :msp_sneaky:

7

 

[TLSF150]

Well I put it together and fired her up.. I started with the needles 1.25 turns out and leaned the L needle untill the RPMs started to rise like its running out of gas then richened it back up untill the idle settled back down to a nice constant speed.. let the saw idle for about 15-20 seconds then went from idle to WOT and it responded great no hesitation at all so I think the L needle is okay but the H needle I leaned out but couldnt really distinguish if it was "4 stroking" or not so I richened it back up and left it for the time being untill I get a log to do some testing on..

You guys were right it is alot louder now.. but I like it its got a nice popping noise now like a little motorcycle or somthing lol..

 

[Fifelaker]

but the H needle I leaned out but couldnt really distinguish if it was "4 stroking" or not so I richened it back up and left it for the time being untill I get a log to do some testing on..

..

You need to richen the high to get it to fourstroke.

 

[TLSF150]

I assumed it would already be 4 stroking at 1 1/4 turns out so I was leaning it expecting it to smooth out and then id be able to tell the difference between it 4 stroking or not.. but maybe 1 1/4 is still to lean?? ill richen it up a little more and see what happens

 

[H 2 H]

I actually dont know how it runs with the muffler mod... I just cut it tonight and planned on tuning it tomorrow.. If its to much I could always close off the bottom port..

The bottom hole is the most important one IMO

It means the exhaust has a straight shot out of the cylinder

On several MM (on this series of saws) I've done the H is around 2 1/2 turns out and the L is 1 1/2 turns out depends on big of a opening your muffler has

I've started with small open on the muffler and made it bigger till it lost performance if it got to big I just welded a piece back in the muffler or place a flat piece of metal for a cover and made openings on each side of the muffler with deflectors

You never know to you try different thing

 

[TLSF150]

By bottom port I mean the slot under the hole I dremeled out.. The hole is directly in front of the exhuast port on the cylinder so the exhuast has a straight path through the baffle and out of that hole.. the slot under it is below the baffle so the exhaust has to go through the baffle then out of the slot

 

[H 2 H]

 

[TLSF150]

Are you saying I should take the baffle out?? wouldnt that be even less resistance added to whats already been done??

Anyway the saw is running stupid rich on top end right now so I guess its been 4 stroking the entire time? Im just worried about leaning it out to the point of damaging the piston it was much easing to tell when the L needle was getting to rich or lean.. this H needle I lean it out and it continues to sound the same.. I guess ill ask my boss to help me with it tomorrow at work if I cant get it dialed in by then..

I thought it would be a piece of cake to tune since I use to race Nitro fueled RC cars and have alot of experience tuning them.. Im just not sure about this "4 stroking" sound im suppose to be hearing I guess