( Part 2 siezures) Oil Ratio and Fuel Poll
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RiverRat2
Serio Tree Freak
Dang it TW!!!!
That makes my head hurt,,,,,and it is quite logical BTW and from the failed saws Ive seen come into my buds Stihl dealership in general from what I have seen air leaks/on carbs/intakes and faulty seals along with fuel delivery leanouts would attribiute to the majority that ive seen and then I would suppose dirty air filters/ take out a few as well
That makes my head hurt,,,,,and it is quite logical BTW and from the failed saws Ive seen come into my buds Stihl dealership in general from what I have seen air leaks/on carbs/intakes and faulty seals along with fuel delivery leanouts would attribiute to the majority that ive seen and then I would suppose dirty air filters/ take out a few as well
timberwolf
Addicted to ArboristSite
On the air filters, not sure, the more the air filter is blocked up, the more the mixture is richened. If there is a lower pressure in the intake/carb bore, more fuel will be drawn in, not less. However if there is a downstream air leak more air will also be sucked through it, effectivly worsening the air leak.
Now if someone with a plugged filter leans the carb to get it running as best possible or to full factory RPM it could be too lean in the cut or after setting the carb with a plugged carb someone then cleans the filter it would end up too lean.
Lots of filters tend to do a better job filtering out crap once they get plugged up a bit.
Now if someone with a plugged filter leans the carb to get it running as best possible or to full factory RPM it could be too lean in the cut or after setting the carb with a plugged carb someone then cleans the filter it would end up too lean.
Lots of filters tend to do a better job filtering out crap once they get plugged up a bit.
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RiverRat2
Serio Tree Freak
OK then,,,,
if you use dyno premix and it is running too rich because of a plugged Air filter and a saw that is very dirty IE, flywheel fins cylinder fins and top cylinder cover,,,and it gets hot,,,, and you keep running it,,,,,and you are compressing dead dinosours,,,,,,guess what you get,,,, stuck like chuck,,, almost looks like diamonds and an overly rich, overheated stuck piston is He_ _ to get unstuck!!!!!!!!!!!!
too rich can also be a problem!!!!!!!
if you use dyno premix and it is running too rich because of a plugged Air filter and a saw that is very dirty IE, flywheel fins cylinder fins and top cylinder cover,,,and it gets hot,,,, and you keep running it,,,,,and you are compressing dead dinosours,,,,,,guess what you get,,,, stuck like chuck,,, almost looks like diamonds and an overly rich, overheated stuck piston is He_ _ to get unstuck!!!!!!!!!!!!
too rich can also be a problem!!!!!!!
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timberwolf
Addicted to ArboristSite
Good point
Al Smith
Addicted to ArboristSite
As I said ,I never cooked a saw,from lack of oil or air infusion.
What I did do,just once was mistakenly pour anti freeze in a weedwacker.I used to mix my gas in old anti freeze gallon jugs,you see.It didn't dawn on me what happened to the weedwacker until I put "antifreeze" in my old truck and smelled gasoline,duh.The weedwacker is still alive and well,abiding in the shed with about 40 chainsaws.The old truck survived as well.
What I did do,just once was mistakenly pour anti freeze in a weedwacker.I used to mix my gas in old anti freeze gallon jugs,you see.It didn't dawn on me what happened to the weedwacker until I put "antifreeze" in my old truck and smelled gasoline,duh.The weedwacker is still alive and well,abiding in the shed with about 40 chainsaws.The old truck survived as well.
A engine was never ruined by using too much oil......
I use 32:1 in most applications, except my Yamaha outboards, which get ran at 50:1(call for 100:1).
If I where milling or using excessively long bars with a small power head I wouldn't hesitate to use 20:1.
FWIW I have ran engines at 20-16:1 ratios and you would be amazed at how clean they are internally. This is with high quality oil.
I use 32:1 in most applications, except my Yamaha outboards, which get ran at 50:1(call for 100:1).
If I where milling or using excessively long bars with a small power head I wouldn't hesitate to use 20:1.
FWIW I have ran engines at 20-16:1 ratios and you would be amazed at how clean they are internally. This is with high quality oil.
timberwolf
Addicted to ArboristSite
I have seen this also Ben, running lots of oil often leads to less build up of carbon than running less oil. Almost as if the excess oil keeps washing away deposits before they get a chance to get caked on. In that respect I had good results with Castrol 927 mixed nice and rich and the saw run fairly lean at the edge of 2 stroking a fair bit beyond factory max rpm.
Makes sense when you consider you have double the detergents/dispersants goping through a engine run at 20:1 vs. one ran at 50:1.
The Mufflers can get gooey though, especially with a castor based oil like 927. I would also think that if the load when up that you would start to combust the castor oil and the engine would get pretty nasty in a hurry. Castor has such a high end point it typically doesn't combust. Saws after all are loaded pretty lightly unless your milling of forcing a dull chain through the wood.
Al Smith
Addicted to ArboristSite
Back in the 60's they ran those old racing go-karts on about 20 to one ratio,using alkie-nitro,caster oil.They would gooey up the tires,the backs of the seats,what a mess,however they never siezed although I've seen a few self destruct.The area around the track,after a 10 round heat race was just a thick blue fog.
The real old saws as well as outboard motors all ran on 16 to 1 .There are still a few old Evinrude,Johnson and Mercury motors that were made during the 50's that are still in use today,running just dandy,although perhaps not in constant usage.These old boat motors were pretty dependable but they left an oil slick in the water which really is not a good thing,evironmentally speaking.
The real old saws as well as outboard motors all ran on 16 to 1 .There are still a few old Evinrude,Johnson and Mercury motors that were made during the 50's that are still in use today,running just dandy,although perhaps not in constant usage.These old boat motors were pretty dependable but they left an oil slick in the water which really is not a good thing,evironmentally speaking.
timberwolf
Addicted to ArboristSite
I messed about with some of those old out boards, one thing you did not forget, was to have a spare spark plug or 6.
But they would idle down unlike any new 2 stroke outboard.
But they would idle down unlike any new 2 stroke outboard.
Times have changed. In the present the only smoke you see at the kart track are at the starting line and during warm up. Their may be a few old cranks still using castor and smoking, but not the majority.
At 16:1 a shifter cart is smokeless except for operation prior to being up to full operating temps. When tuned properly the pistons come out with a light creamed coffee patina and the ports/exhaust are bone dry. This is when using Mobil 2R and Phillips 66 Xamax and I have seen it with my own eyes.
Even a MX bike will run clean at 16:1 when its operated in a place like the sand dunes or on a road race course.
Diesel JD
ArboristSite Guru
Never seized a saw or any other 2 cycle. I voted at 50:1 and 93 Octane in the other thread, but its actually closer to 45:1, I used to run regular or mid grade, but now I take no chances. I think the key to engine longevity is using at or slightly more than factory specs for oil, and not setting the carbs up too lean. Always have used Echo or Stihl oil, sometimes some no name brand stuff, and even once in awhile some of the Johnson/Evinrude Ficht oil from the boat(which I do not recommend).
I find 25 to 1 burns very clean if you service your saw when needed. That means taking care of your air filter, blowing the sawdust from your cooling fins, and keeping the carb adjustment where it should be.
The only reason I would go leaner on oil would be for warranty requirements.
If a saw is borderline on compression the richer oil ratios can improve it over a leaner oil mix,just don't forget to adjust the carb to the mix.
In my early sawing years I used 15 or 16 to1 and adjusted the carb on the rich side and would clean the carbon from the exhaust port occaisionly. These days with 25 to 1 and I adjust the carb for a little more rpm and I see very little carbon on my exhaust port,not enough to worry about carbon removal.
A lot of saws I work on that were run on leaner oil mixes have plenty of carbon to remove due to poor air filter service or rich fuel to air mix.
I would say most oil today burns a bit cleaner also.
I do know a mechanic - farmer who uses Shell rotella for every thing including his echo 660evl which he has had since new,15 to 20 years.He mixes it whatever it says on the cap which I think is 20 to1 or there about. He said that is all he ever used in it and he thought it was still with the original spark plug. I am sure it has cut plenty of wood in them years.
The only reason I would go leaner on oil would be for warranty requirements.
If a saw is borderline on compression the richer oil ratios can improve it over a leaner oil mix,just don't forget to adjust the carb to the mix.
In my early sawing years I used 15 or 16 to1 and adjusted the carb on the rich side and would clean the carbon from the exhaust port occaisionly. These days with 25 to 1 and I adjust the carb for a little more rpm and I see very little carbon on my exhaust port,not enough to worry about carbon removal.
A lot of saws I work on that were run on leaner oil mixes have plenty of carbon to remove due to poor air filter service or rich fuel to air mix.
I would say most oil today burns a bit cleaner also.
I do know a mechanic - farmer who uses Shell rotella for every thing including his echo 660evl which he has had since new,15 to 20 years.He mixes it whatever it says on the cap which I think is 20 to1 or there about. He said that is all he ever used in it and he thought it was still with the original spark plug. I am sure it has cut plenty of wood in them years.
timberwolf
Addicted to ArboristSite
A good number of people have responded on the polls and the numbers are starting to get stable. Though some people have checked more than one fuel and one oil mix so the % add up to over 100% and needed to be corrected back down to add up to 100%
I think there are a few interesting observations that can be made.
1 over 50% of people reporting a siezed saw report that it was siezed on 87 octane fuel, yet only about 10% of users put 87 octane in their saws. (very strong correlation)
2 About 40% of people put 50:1 mix in and over 60% of the saws were reported to have siezed on 50:1 mix (significant corolation)
3 Only 10% or a little less of users report puting 32:1 in their saws, yet about 25% of the saws that siezed were reported to have siezed on 32:1 (strong correlation)
4 about 30% of users put 40:1 in their saws, yet only one siezures was reported on 40:1 (4%) (very strong correlation)
A couple questions and thoughts come to mind:
At 40:1 very few siezures were reported, far less than at 50:1 despite the number of people using 40:1 and 50:1 being quite close.
Why was there a high number of 32:1 siezures, could this be carbon build up problems, or could this be because people that put 32:1 in their saws use them for extreme duity like milling? I would like to hear more about these 32:1 siezures.
Maybe there is a need to look at what people use there saws for and how many hours they put on them?
Not realy statistically sound to draw a comparison between a homeowner grade saw with 50:1 mix that cuts a couple cords a year to a pro saw milling or bucking on a pile 8 hours a day mixed at 32:1.
I think there are a few interesting observations that can be made.
1 over 50% of people reporting a siezed saw report that it was siezed on 87 octane fuel, yet only about 10% of users put 87 octane in their saws. (very strong correlation)
2 About 40% of people put 50:1 mix in and over 60% of the saws were reported to have siezed on 50:1 mix (significant corolation)
3 Only 10% or a little less of users report puting 32:1 in their saws, yet about 25% of the saws that siezed were reported to have siezed on 32:1 (strong correlation)
4 about 30% of users put 40:1 in their saws, yet only one siezures was reported on 40:1 (4%) (very strong correlation)
A couple questions and thoughts come to mind:
At 40:1 very few siezures were reported, far less than at 50:1 despite the number of people using 40:1 and 50:1 being quite close.
Why was there a high number of 32:1 siezures, could this be carbon build up problems, or could this be because people that put 32:1 in their saws use them for extreme duity like milling? I would like to hear more about these 32:1 siezures.
Maybe there is a need to look at what people use there saws for and how many hours they put on them?
Not realy statistically sound to draw a comparison between a homeowner grade saw with 50:1 mix that cuts a couple cords a year to a pro saw milling or bucking on a pile 8 hours a day mixed at 32:1.
RiverRat2
Serio Tree Freak
Good work TW
Tried to rep ya but Im hosed,,,,,,,,,
Tried to rep ya but Im hosed,,,,,,,,,
This poll is statistically useless. It would be impossible to draw any sort of conclusion with a sample size this small.
timberwolf
Addicted to ArboristSite
Then, I welcome you to do better. Maybe the whole thead should be pulled, maybe it is not worth trying to contribute here.
umpkin2: 32:1 in everything
I now run 32:1 in everything. Even my old xp and C series Homelites with a 30" bar. Haven't had any problems! I used citgo semi synthetic or mobil 2T. Barely any smoke, and they run clean. I have an uncle that argues I should use at least 16:1 in my old Homelites! I used to, but not anymore! Oil, has come a long way, even in the last 5- 10 years!
I now run 32:1 in everything. Even my old xp and C series Homelites with a 30" bar. Haven't had any problems! I used citgo semi synthetic or mobil 2T. Barely any smoke, and they run clean. I have an uncle that argues I should use at least 16:1 in my old Homelites! I used to, but not anymore! Oil, has come a long way, even in the last 5- 10 years!
