That's more or less what I have and being a contact thermometer and will lag too far behind the real temp inside the saw.
An EGT gauge will be a lot quicker
Killed the MS880 while milling
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That's more or less what I have and being a contact thermometer and will lag too far behind the real temp inside the saw.
An EGT gauge will be a lot quicker
jaycky
stihl user
Hmmm
Rx7man
Cattle Rubbing Post
Just speaking from my experience with my old husky saws, I noticed a slight power improvement running a bit richer than 40:1 when I had to make extended heavy cuts, and once they were ported, they really appreciated the extra oil of 32:1. If I do mostly limbing, and cutting small stuff, the leaner mix is fine. I had the compression on mine bumped up to 185PSI @ 1200ft elevation.
On a saw that cuts for a long time without being let up, like on a mill, I think I'd run a little more oil on it.
On a saw that cuts for a long time without being let up, like on a mill, I think I'd run a little more oil on it.
There's no such thing as a "lean mix".
Leaness and richness refer to the "air to gas" ratio.
"Gas to lube" ratios are just "gas to lube" ratios, and should not be confused with the previous.
Running lower "oil to gas" ratios without retuning the saw will reduce the amount of gas relative to the amount of air taken up through the carby, which actually ends up "leaning the saw" and that's why it may seem like there's more power. It might seem like it's taking more care of a the saw but it's actually pushing things the wrong way so it is really important to retune the saw and make it rich using the H screw.
The extra lube actually does little to nothing towards cooling the internals of the saw, that is done by the unburnt gas. Modern saws will in fact run happily with very little lube in the mix (even a 100:1) but you'd have to be careful about getting the ratio, and tuning the saw , right because a slight mistake the wrong way will be a problem. 50:1 is recommended by manufacturers because that is about the practical limit that operators (especially in the field) can make up without getting into trouble.
The majority of saws that get cooked, especially when milling, are a result of running too lean i.e. high "air to gas ratios" , irrespective of the lube to gas ratio used. Extra lube in the mix won't save the saw from frying and in fact may be counterproductive.
My experience is that using extra lube just generates an increase in the invisible fog of unburnt oil and smoke suppressant gunk around the operator and ratios of 25:1 give me a headache., and my clothes hair and chaps are greasier than usual after a full days milling.
SDB777
I find unique timber and cut it up
Someone must have been reallllly bored to go back into a topic that is 4-1/2 years old
Scott (whew, shoveling is hard) B
Scott (whew, shoveling is hard) B
Rx7man
Cattle Rubbing Post
I got my information from http://forum.dirtrider.com/discussion/7169620/spooge-101-/p1
I agree that too much isn't good, but too little is more costly more quickly. a little more oil supposedly helps seal the rings better and leads to more power, I have distinctly noticed the difference between a 40:1 mix and a 32:1 mix... would be interesting for chadih to run a dyno test.
Yes, more oil in the fuel can be counterproductive if the air fuel mix isn't adjusted.
But I'm going to continue using the term "lean mix", because if you really get down to it, "Lean" means Not fat, and that refers to oil!.. There is a difference between not enough fuel in the air, and not enough oil in the fuel
I agree that too much isn't good, but too little is more costly more quickly. a little more oil supposedly helps seal the rings better and leads to more power, I have distinctly noticed the difference between a 40:1 mix and a 32:1 mix... would be interesting for chadih to run a dyno test.
Yes, more oil in the fuel can be counterproductive if the air fuel mix isn't adjusted.
But I'm going to continue using the term "lean mix", because if you really get down to it, "Lean" means Not fat, and that refers to oil!.. There is a difference between not enough fuel in the air, and not enough oil in the fuel
Bob's right, but since using the correct terminology isn't a requirement, carry on.
The reason I keep responding to this incorrect terminology every time it comes up in this forum is to protect newbs who might otherwise think that protecting the saw while milling just requires using more lube in the mix and they don't understand that retuning is needed. If their saw is already borderline "lean" then the extra oil can push it further into "leanness".
Kicker_92
ArboristSite Operative
Someone must have been reallllly bored to go back into a topic that is 4-1/2 years old
Scott (whew, shoveling is hard) B
Wow, didn't realize it's been that long! That same MS880 is still up and running now. High compression, lots of port work, and running 3/8" 0.050" chain, it chews wood pretty well.
I have a Woodland bandmill now, so only use the alaskan to get logs into quarters now.
Even at only 9hp, the bandmill is just much more efficient.
Thanks for bringing back this old thread! Next will be the old "CSM like a swing mill" one...
Ryan
jaycky
stihl user
I've been reading these threads scouring actually debating on leaving my 880 stock with limited carb now does this mean I'm in the already lean department? Jesus I got to say the fear factor has made me wonder or re think about getting this saws carb reworked or should I just leave it alone?
betterbuilt
I build stuff from milled slabs
I thought the 880 had a limited coil, not a limited carb.
jaycky
stihl user
Yea what he said the adjustment on this ms 880 is very little caps limiting further carb adjusting I meant. Is it fine cutting caps and leaving coil as it is ? All these threads have made me paranoid as $&)@
The last thing I want is to pooch this thing milling.. I am actually doubting myself with this saw now. Last thing I want is to burn it up so I've been scouring threads reading as much info as possible every time I read something good I find 4 things bad said... Set my mind at ease please...
The last thing I want is to pooch this thing milling.. I am actually doubting myself with this saw now. Last thing I want is to burn it up so I've been scouring threads reading as much info as possible every time I read something good I find 4 things bad said... Set my mind at ease please...
betterbuilt
I build stuff from milled slabs
Mine hasn't needed any adjustments yet. It's always right where it should be. I left it stock. I had the same worries reading they are lean from the factory. I strapped a big bar on it and buried it in some wood. I ran maybe 2 gallons thru it cutting firewood before I milled with it. Keep your chain sharp, don't run it with the brake on, listen to it. It'll tell you something is wrong. shut it off and figure out what it is. I broke a clutch spring the first week I had it. I only fill up a gallon can and only use it for a week then I dump it in my truck and start over. Seriously it's a saw, eventually it's gonna break, they all do. Some more then others. Watch Brads video on tuning in the wood. Most issues are from not paying attention.
jaycky
stihl user
Alright good I'm gonna take and the 661 out shortly with smaller bar and chop wood with it for break in. After that will then hook up to mill.
betterbuilt
I build stuff from milled slabs
I usually run 50-1 for firewood and 40-1 for milling. Watch brads video on tuning. listen for that blubber and if it not doing it you need to tune it. 661 is an auto tune. I haven't heard of anyone milling with it yet. You may be the first.
jaycky
stihl user
I will be tuning this saw regularly I think just for keeping my mind at ease.
I have that premix from stihl that I have in all my saws while not in use 50:1 so firewood and break in for the first 14 tanks.
I have that premix from stihl that I have in all my saws while not in use 50:1 so firewood and break in for the first 14 tanks.
Rx7man
Cattle Rubbing Post
Did anyone look at that link I posted? While it's true that more oil in the mix leans out the fuel mixture, if you're that close to the bleeding edge of being lean, you're going to be cooking the engine anyhow... Going from a 50:1 mix (2%) to a 32:1 mix (3.1%) is just over 1% change... It's equivalent to less that 1000 ft elevation drop,... Looking at air/fuel ratios, you have a 'perfect' ratio at about 14:1, but make most power around 12.5:1, and many turbo vehicles will run as low as 11:1 for the cooling effect of the fuel.
Certainly it's possible for extra oil to push it over the brink.
Engines need a certain amount of oil, and a certain amount of fuel,.. the problem is they're getting both at once, so if you lean the saw out you're starving it for oil at the same time when you're running a 50:1 mix. A second problem with not running sufficient oil through the engine is the reduced piston sealing, and that means hot combustion gases go by the piston and rings, and heat them.
From that link, they did a dyno test on a 125cc dirt bike engine.., and jetted it properly for each oil mix
I can say I noticed a significant increase in power in my stock saws when I increased the oil from 40:1 to 30:1.. And since a milling saw is working a long time at full throttle in a single cut, I think it would benefit it.
Certainly it's possible for extra oil to push it over the brink.
Engines need a certain amount of oil, and a certain amount of fuel,.. the problem is they're getting both at once, so if you lean the saw out you're starving it for oil at the same time when you're running a 50:1 mix. A second problem with not running sufficient oil through the engine is the reduced piston sealing, and that means hot combustion gases go by the piston and rings, and heat them.
From that link, they did a dyno test on a 125cc dirt bike engine.., and jetted it properly for each oil mix
I can say I noticed a significant increase in power in my stock saws when I increased the oil from 40:1 to 30:1.. And since a milling saw is working a long time at full throttle in a single cut, I think it would benefit it.
JS929
ArboristSite Lurker
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In analysing the circumstance I'd be asking myself the following
How does a bar get pinched when milling?
What type of wood were you cutting?
How long had it been since the chain was sharpened?
What fuel/lube mix are you running?
How many RPM below max have you got the H screw set at ?
How much pushing was happening?
Fear of this is what leads me to this.
I reckon your cylinder is salvageable.
Those are the exact same series of questions that I asked. I want to know how the bar got stuck milling. I'm not saying it isn't possible, but I have never done it unless the wedges slip out and I go to remove the saw from between the slab and cant.
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