help tuning saw and tach

[aaronmach1]

what i mean is how are you guys getting to the plug wire to wrap it this many times. i cant hardly get to mine to wrap it very well. didnt get a chance to work on the saw this weekend, i will this week, this weekend was taken up working on this:

just take the top cover of it aint a tear down

Im guessing ill need a special star head looking bit then to pull about 8 screws and the handle. I can easily pull the back cover that goes over the air filter area but that doesnt get me to the plug wire very good at all.

 

[deye223]

Im guessing ill need a special star head looking bit then to pull about 8 screws and the handle. I can easily pull the back cover that goes over the air filter area but that doesnt get me to the plug wire very good at all.

:confuse: you can pull a motor out of a car but can't take a top cover of a chainsaw ????????

 

[aaronmach1]

you can pull a motor out of a car but can't take a top cover of a chainsaw ????????

was just asking if there was an easier way. instead of pulling the carb and everything to remove the orange cover.

 

[deye223]

was just asking if there was an easier way. instead of pulling the carb and everything to remove the orange cover.

think i need to have a look at these home owner saws they sound like a PITA all the saws i've had ya just pop the top cover and presto take's 1 min cheers

 

[aaronmach1]

stock muffler purchased.

 

[blazer75]

you never stated where in michigan you are. Im in the metro detroit area, I may be able help.

The racing/creeping idle and stalling followed by a hard start are classic air leak symptoms. Crank seals, carb gasket, etc...

 

[H 2 H]

what i mean is how are you guys getting to the plug wire to wrap it this many times. i cant hardly get to mine to wrap it very well. didnt get a chance to work on the saw this weekend, i will this week, this weekend was taken up working on this:

I went thru the white sheild that holds the intake boot on - 3 holes one for the wire and the other two for a wire wrap to hold the wire if you dont want to drill holes in yours pick up another sheild on freebay and drill that one


The last one I did runs the best the one I did more polishing on with the 90% MM


Both of mine the idle stays about plus or minus 100 rpm at 2700; like what was said check for air leaks


Sorry not getting back to this thread earlier

 

[aaronmach1]

i put a stock muff back on and readjusted the carb and still have the issues so its going back to stihl today for warranty repair. we will see how that goes!

 

[aaronmach1]

got it back from stihl yesterday. charged me $20 for a carb clean and he said there was water in the gas. Runs great now.

 

[nmurph]

Water in ethanol is the red herring for every runnability problem. It likely had something that wasn't tight. Water wouldn't cause an excessively high WOT.
Glad you got it going...now, get that MM back on it!!

 

[T0RN4D0]

I already posted this, but it can't hurt if i post it here also. I got the tach today and tried to tune my MMed 046 with it. It seems to run a bit fast at 13500 (unloaded with 18" b&c)...

I posted a video on youtube, you can kind of see the tach in the backgroud... should have put it in the front. Anyways what im more interested in is the sound, does it sound OK or is this too lean?

stihl 046 tunning - YouTube

 

[nmurph]

That's rich...you've got at least 500-1000rpm left. I can't get a good listen bc it is clipping out.

 

[SierraWoodsman]

That's rich...you've got at least 500-1000rpm left. I can't get a good listen bc it is clipping out.

I would agree with this but your not far off from where you should be. Better a lil bit rich than too lean. You can hear the saw "Clean up" under load in the cut and this tells you your close.
It makes it tough to judge "in the cut" RPM in your video due to the tach delay. I Tach-tuned my MM'd saws this last weekend and
no-load RPM's were running anywhere from 12000-13800 and loaded all were holding right @ 9800-11000 "in the cut on 20" pine
depending on the size saw I was using.

 

[T0RN4D0]

Yes, the tach is a bit slow. And yes the RPM vary for a couple 100... Oh and if the video (audio) is clipping out try setting it to 360p, i set it to 720p so the tach is somewhat readable.

If it's not too lean than i think i'll leave it there for now. Might make another vid when i get some wood thats not cut up yet.

Thanks for the input.

 

[aaronmach1]

since i got the 250 back the other day i ran it once the other night.(stock muff) he said he cleaned carb etc. While running it i cant get it to 4 stroke at all with the stock carb setting.(3/4 out) so i took off the plastic limiter and turned the H 1 turn out then more and more. i cant get it to 4 stroke. any ideas?

 

[T0RN4D0]

There is one thing that bothers me with tuning with a tach. From most sources i've read that you should tune with b&c and no load and shoot for the given rpm (say 13.500 for 046). But for example i have a 18" set that turns smooth as butter, and a 25" b&c that doesn't turn as smooth. Its a new (cheap) set and it will probably get better, but its beside the point. My point is that for example a 16" b&c will create less friction than a 32", so for 13.500rpm the saw will have to run leaner to hit 13.500 "no load".

I'm guessing that I should just aim for lower RPM if tuning with a bigger bar.

 

[aaronmach1]

i put the modded muff back on. i ended up at 2 out on the H screw. This time i messed with the screw while at full throttle. So i know it was making a differance, i could hear it in engine speed and the 4 stroking. What i cant figure out is why on this saw the 4 stroking is less pronounced than the videos i hear posted on here or than my 170. I tried to make a video tonight but it doesnt pick up the 4 stroking. Anyone know why its less noticeable on this saw?

 

[SierraWoodsman]

Bar length is yet Another factor to consider, but far from the only one.

There is one thing that bothers me with tuning with a tach. From most sources i've read that you should tune with b&c and no load and shoot for the given rpm (say 13.500 for 046). But for example i have a 18" set that turns smooth as butter, and a 25" b&c that doesn't turn as smooth. Its a new (cheap) set and it will probably get better, but its beside the point. My point is that for example a 16" b&c will create less friction than a 32", so for 13.500rpm the saw will have to run leaner to hit 13.500 "no load".

I'm guessing that I should just aim for lower RPM if tuning with a bigger bar.

I Think there's somthing to what your saying here. I Came to the same conclusion. As a Point of reference after warm-up the stock 562 wound right up to 13800 no load wearing a new sprocket-nose 20", and ran about 10000 in the cut (give or take 400). Where as the 395 wearing a 36" Sprocket nose seemed to be in the "sweet spot" @ 12400 no- load, and was running an impressive 10800 to 11200 in the cut (likely partially effected by running full-skip square). I tried leaning out the 395 a touch more to try to get 12800-13000 (no load) and found it reduce it's torque/performance so I Richened it back up again to where it first was and regained the torque. There are so many factors that play into this equation, so trying to reach an specific RPM such as 13500 in "All conditions" is an over-simplification at best, and possibly dangerous for the saw engine at worst IMHO. Even With all the technolgy the experienced trained ear still may prove the most valuable tool here.

 

[T0RN4D0]

I don't trust my cheap tach too much either. I believe i tuned my 046 just right now, as i can hear it more clearly. With 026 at 14k rpm its just white noise inside my head :msp_scared:

I uploaded another video, i leaned it out twice for a tiny bit. I'm thinking the second cut may be about right, and the third a bit lean? Also pulled the plug after i turned it off, pic attached.

026 oak tune - YouTube

View attachment 249489

 

[Joe Kidd]

I Think there's somthing to what your saying here. I Came to the same conclusion. As a Point of reference after warm-up the stock 562 wound right up to 13800 no load wearing a new sprocket-nose 20", and ran about 10000 in the cut (give or take 400). Where as the 395 wearing a 36" Sprocket nose seemed to be in the "sweet spot" @ 12400 no- load, and was running an impressive 10800 to 11200 in the cut (likely partially effected by running full-skip square). I tried leaning out the 395 a touch more to try to get 12800-13000 (no load) and found it reduce it's torque/performance so I Richened it back up again to where it first was and regained the torque. There are so many factors that play into this equation, so trying to reach an specific RPM such as 13500 in "All conditions" is an over-simplification at best, and possibly dangerous for the saw engine at worst IMHO. Even With all the technolgy the experienced trained ear still may prove the most valuable tool here.

Right on. My 395 sounds a bit rich @12600(28" b&c full comp), but like yours it cuts well and cleans up nicely in the wood. So there it'll stay.