Stihl chainsaws

So I've ran stihl chainsaws for about 15 years now with pretty good luck until the other day. My small saw (ms170) lost power and and started making a chirping sound so I took it to a small engine shop. He said that the 50 to 1 mixture is not enough oil and that he has ran 32 to 1 for close to 30 years in saws that are almost that old now with no problems. He also said that he has had close to 20 stihl saws come through his shop this year burnt up with scarred pistons that he said is from using the 50 to 1 mixture. What do you guys think?

My 029 Farm boss is 20 years old and I have always mixed my gas at 50 to 1 with no problems. Also have a Stihl weed whacker that old and it gets 50 to 1 gas also.

Do you use Stihl's oil?

Those saws are made to run 50:1. Of course theyll run on 32:1 as well, but there is no way running 50:1 will ruin one. There are always a few folks that think they know better than everyone else. If they actually did know more, theyd be selling their own brand of saw instead of working on them.

Iv heard that a guy is to warm them up frist before running them hard. They say that if you start out with running them fast that the piston heats up to quick and can wreck the piston. I have run mine at 40 to 1 with good luck an they just smoke more. Alot of guys have told me that the saws an weed eater is 50 to 1 and that's to much oil for them but they work good and I would rather buy a spark plug instead of a piston.

Yes. I use the stihl oil in the grey or silver bottle.

My experience is that the vast majority of saw problems blamed on the mix ratio or type of oil is actually not that at all but from running lean and it is very easy to tell. Remove the muffler and spark plug. Then run the piston down and look at the cylinder wall under the exhaust port, then look at the back side through the exhaust port. Then run the piston up slowly while looking at it from the exhaust port. If the piston and wall is heavily scored on the exhaust side but not the intake side wall is not then the saw was run lean. That being said current saws are tuned to the ragged edge for lean so they pass emissions and the slightest bit of varnish, dirt or old fuel puts them in melt down if run hard. I like to have the pile of money thrown away each year on chainsaws due solely to the use of old stale mix.

I have 4 Stihl saws the oldest one a 026 bought new being close to 35, two 028's with 16 and 20 inch bars and the newest being a MS211 being 7 years old and have never replaced a piston.

I always use genuine Stihl oil 50-1

I run 25:1 in my Stihl saw and my Echo hedge trimmer.
I use Stihl oil only.
The old 2 cycle mechanic who worked on them all his working life told me they need that extra oil if you work them hard.
So I have been doing that for years with no problems.
And they don't smoke any more than normal.
Richard in NW SC

I have to agree it's more due to running lean.

Waaayyyy back when, I picked up some oil that said it was good to 100:1. I used it at ~75:1. Saw is still going today. I did chicken out and went back to somewhere between 40 and 32:1 after I used up that bottle.


Today I use TSC 2cyl oil and refill a measuring bottle I have. Still at about 32:1 Probably more like 35. This is in a Stihl 026 and now also a 044

I tend to run a richer mix than recommended and my saws do smoke when cold. My weed eater wouldn't run so I googled the problem and found out about the screen in the exhaust and it was plugged from to much oil. I am not worried about sparks so I removed it and the weed eater runs perfect. I hope it doesn't cause other problems.

Sounds good to me. I've been running 50 to 1 in the Stihl saw, 40 to 1 in the weedeater and 32 to 1 in the lawnmower. I would rather just have one fuel.

This is what he said he uses. 32 to 1

Illinois Deere
I wouldn't run that in anything but water cooled outboards.
TCW-3 is for water cooled 2 stroke motors that run cooler
than air cooled.

i have several 2 cycle units. i have a lawn boy silver series mower that i use for trimming. it runs 32 to 1. i run everything on 32 to 1 so i only mix one fuel. i do use stihl oil, and all my stihl saws, trimmers and lawn blower all get 32 to 1 no problems.

I am not at all trying to argue but this man is 70 years old and made his entire living working on small engines and says he's been using this for probably 15 years.

Almost all the saws I have looked at the past few years were being nursed along way too lean. Finding and adjusting the mixture screws is a chore. As the seals get a little stiff or a bit of dirt gets inside the carb they run way too hot and lean. I tend to err on the over when it comes to oil mixture. If it says it makes two gallons I hold back a quart or so.

Illinois Deere,

From 32 to 1 ratio to 40 to 1 ratio on everything....My experience (40 years or so),with zero problems

Guido.

I run 50:1 in all, no issues, also believe running rich enough mixture is prime cause of scored pistons.

I used to do same but then it was just to much messing around. I run 40 to 1 in that saw,weedeatter and the golf cart and the all run good.

I don't want to sound negative, but "Super Tech" is Walmart's cheap brand of lubricants.

With 50 to 1 ratio are you running a full synthetic oil such as Stihl Ulta in silver bottle? Petroleum based oil might require a stronger mix.

I've had the same results as 300jk. My heavily-used MS290 is 15+ years old and it still runs fine. I recently retired a Stihl string trimmer that was 20 years old because the clutch is wore out but the engine is still good. Both always get (got in the case of the retired trimmer) a 50:1 mix of Stihl oil with regular gas and I've never seen a need to go stronger on the oil. My new Stihl trimmer/pole saw combo tool also calls for the 50:1 mix and I expect many years of service from it too.

I buy all my oils from stihl shop and go exactly as it says been doing this for 40 years never once had internal engine failure I think some guys are just to cheap to do it right and then want to blame everything and everybody for there failures

Read the label! That TC W3 is for liquid cooled engines only!

Ever look at the ratios used by automatic oil injected 2 cycles? They max out at 50:1, drop down to 200:1 at idle!

Extra oil, cheap oil, (which that is, and there is a big difference), will accomplish 2 things, lean the mixture because there is less gas more oil going through the main jet, causing the engine to run hotter, the extra oil will then begin to cook inside the cylinder adhering to the exhaust side of the cylinder wall and piston skirt, reducing the clearance until it has a seizure.

The best solution is to run the exact ratio the mfg requires, run premium synthetic oil, keep the fuel system clean and adjusted properly, keep the outside clear of chips, grass, mud dobbers or anything that blocks airflow, and keep the RPM in the proper range, don't lug the engine!

I have been using Opti-2 for 20 years. It is synthetic, it is for all ratio's, has fuel stabilizer in it as well. It is very good stuff. You can buy it at most hardware stores. It comes in 1 or 2 gallon mix tubes or you can buy it by the jug. Wouldnt use anything else.
mix here

I use 100:1 synthetic Amsoil in all my Stihl equipment. Have done so for more than 20 years. Never have to change a spark plug, or clean the spark arrestor screen. No ring sticking. Using a borescope, cylinder and piston looks factory fresh. Proper carburetor adjustment, to not run lean, is key to longevity, regardless of make or fuel/oil ratio. My $0.03 worth. zuhnc

I bought a 064AV new in 1985 and used it commercially for the first four years. Still runs great today. Always mixed at 32:1 and have been using hi-test for the last ten years in all my small engines..

Dad has been running the 50:1 with the stihl oil for over 20 years now with no problems. Both the red bottles from past and the newer ones silver/gray. I've been using the same mix for 15 years with no problems and I'm hard on a saw. The 50:1 must not be to bad Dad and a friend were using one of those chainsaw mills last summer with his 056 to saw lumber with it in Walnut and pine and oak. They told me the gas was boiling in the tank when they opened it to fill. So let it set for a bit. I cut a big Oak with it this last week and cut fine with plenty of power on a 28 inch bar.

Dad has been running the 50:1 with the stihl oil for over 20 years now with no problems. Both the red bottles from past and the newer ones silver/gray. I've been using the same mix for 15 years with no problems and I'm hard on a saw. The 50:1 must not be to bad Dad and a friend were using one of those chainsaw mills last summer with his 056 to saw lumber with it in Walnut and pine and oak. They told me the gas was boiling in the tank when they opened it to fill. So let it set for a bit. I cut a big Oak with it this last week and cut fine with plenty of power on a 28 inch bar. I say big it was probably close to 3-1/2 feet across maybe a bit more. Just less than 4 foot maybe.

I tend to run a richer mix than recommended and my saws do smoke when cold. My weed eater wouldn't run so I googled the problem and found out about the screen in the exhaust and it was plugged from to much oil. I am not worried about sparks so I removed it and the weed eater runs perfect. I hope it doesn't cause other problems.

I've run my MS 390 since new in '02 using stihl oil and carefully/accurately mixing the fuel, even rinsing the small bottle out with gasoline and making sure it's all in there. I fill with gasoline just a tad below 1 gallon to be sure it's precisely as called for. The cylinder still has hatch marks, it runs great, I bucked up 7 cords with it this fall, 3 of which were large diameter Elm.
I think people get careless with this 50:1 and thin it more than they realize. If my mix is a little rich, the saw will smoke a fair amount. I don't know about the others, but the 50:1 seems to work just fine the way I mix it.

I run husqvarna saws on account that I like the "smoothness" that their antivibe offers over stihl, but not saying my husqvarnas will/have cut more wood that a stihl. I am not a big fan of that stihl or husqvarna 2 stroke oil. If you want a good, clean, long lasting, reliable 2 stroke, a premium oil for dirtbikes and snowmobiles is going to treat you wayyy better than any saw brand oil. A product such as bel-ray h1R or maxima castor 927 or yamalube 2r or several others. Motorex and redline are excellent brands.
Now, I do some commercial logging and am on very good terms with the local stihl dealership mechanic. she is a cute little thing. I see our outfit kill about one piston per year in either husky or stihl. generally appears to be oil related to me. It is common knowledge within the industry that a modern saw is revving higher than a lot of the earlier counterparts on account of better porting and auto tuning therefore causing premature failure of pto bearings, henceforth allowing a crank seal leak and a lean condition burning up the motor. However, this is a problem more so on the medium to larger displacement saws. Several saw shops are recommending a 40:1 mix over the 50:1 on account of many unforeseen crankshaft and pto bearing failures.

I have done the test with my ratio rite for my dirtbike by putting 3 different oils in the ratio rites, dumping theminto my mix and leaving all 3 hang upside down in my shop to evaluate the coating capability of the 2 stroke oils. Afterall, coating is all we get inside the crankcase with all that gasoline, air, heat, and carbon inside that engine. The husqvarna and stihl oils both miserably failed compared to h1r and castor 927, all were done in seperate ratio rites on the same day and left until evening and the saw brand oild were not even capable of coating the inside of the mix cup. all the oil ran out. I run a 32:1 in both my huskys, one was bought used in 2006 and ran good until i ran it over with a log skidder last summer and rebuilt it. That engine had so many hours on it I had WORE OUT 3 plugs to the point that the electrode would not even fire anymore, ran the plug gap all the way to .150" or so. The ground electrod had worn back half way the the threads, and I did this several times, and It was well worn when I bought it, and that engine showed little wear and no abrasion when I fixed it. Now it has a retimed port and more compression and really snorts but still on 32:1 h1r or maxima castor.

My big saw I bought new in 2007 I think and It has less hours but plenty of time and does run nicely and not too smokey at 32:1. If you buy a marginal quality oil and run it at 32:1 it likely will not burn but will carbon foul and smoke you out. Now, Husqvarna does not even recommend their own "premium" 2 stroke chain saw oil in their powersports engines, at all. Guess why, LACKS COATING CAPABILITY. Just like the stihl.

With this in mind, remember that a tuned saw for a 50:1 mix can easily go to slightly richer/leaner oil mix without severe tuning effect, but venturing to a big oil mix jump requires a retune on the carburetion. I would think a 50:1 tune could safely handle 45:1 maybe 40:1 but a jump from 50:1 to 32:1 would definetly be catastrophic without a carb tune.

Several good resources on saw tuning out there guys. hilltop is a good one. Just remember we have to take into account how is this saw being used? sea level? mountains? fire mitigation? Logging? Tree trimming? With this in mind our saw here in colorado run at 9-10000 feet but in a 90*+ temperature with really dry hot conditions. this means air cooled engines struggle to keep themselves cool all day and gasoline boils very easily. all said, a fireline may well be even worse. On a saw known to have pto bearing issues, heat is the enemy.

I don't work for a Stihl dealer, but I do work on a fair number of those saws in a year at the Echo and Husqvarna dealer. The fuel mix ratio itself is not the problem, as long as it is pretty close to 50:1. (And not more than a month old. Modern fuel does go old pretty quickly.)

The real problem with those MS170 saws is the carburetor is jetted for the fuel mix to meet Federal Emissions and the fuel delivery cannot be made any richer. At least not without modifying the carburetor. So the saw runs lean and with a lean fuel mix there is both not enough fuel keeping it cool or enough oil to lubricate it properly. When a saw comes across my bench and I know it needs 'just a tad bit more fuel' I have to tell the customer their saw needs a new carburetor.

I've got an 064AV also. Pretty rare saw. They soon replaced them with the 066. It really goes thru the wood but my 088AV will outdo it.

4240 Turbo, I believe what you say on oils. That opti -2 oil i use is mixed with a ratio rite cup. It clings to the cup and i have a hard time rinsing it with gas to get it out. I have used Bell-ray oil and it acts the same way in the cup.All must be good oils. I will hang my ratio rite cup upside down the next time i mix oil to see. You really make sense to me with it. Now in comparing oils and comparing dealership mechanics, i bet yours would win.

Yeah. the 4 bearings inside that engine all being lubricated by 2 or 3 ounces of oil for 8-10 hours of use. that is basically one drop per bearing per hour. I use 32:1 because the saw shops have often claimed that the manufacturers are mandated to lean the mix due to emission reasons. The epa does not want any smoke emissions. If anyone has torn down 100 or so 2 cycle engines like myself and seen the difference of ones where you knew the ratio and oil brand, you would undisputedly understand.

This is never ending debate on the chainsaw forums. I'll give you my 2 cents- It's like Butch said, a lot of the problems come not from a lean mix (50-1 or higher) but from air leaks, lean carb settings and lack of maintenance. If you aren't getting enough oil into the crankcase then the piston and bearings will eventually take a beating. I run Dolmar oil at 40-1, I don't lean my carbs way out and I don't use any ethanol gasolines with 2 stroke engines. Works for me.

Air leaks for sure ! I could not figure why the below mentioned saw would at certain times, act like it was running out of fuel or
the position of it when using would contribute to same. I thought maybe the pick-up in the tank needed to be re-orientated as it
may not be immersed in the fuel as the amount in the tank got lower.

Turns out, just needed to make sure the air filter was good and tight after re-installing when cleaning, which I do fairly often.
Problem went away.

Been using High test gas at 32-1 for 30 years. Never a problem. Only use stihl , own a 26, 34, 36 and a 361.