Newbie to running older saws, question on mix ratio

[bwalker]

Well, I blame it on oil because that is what I see. A tar like flow oozing out of the exhaust after being heated up at wide open throttle is not gasoline...

So, these guys are not clearing a pasture. They are trimming around tombstones , brick foundations, trees and shrubs that can be girdled and killed. Pointless to eat off your string trimming grass wide open. I doubt they are ever ran at wide open throttle for more than a few seconds here and there.

It is what it is I suppose.

Chainsaws, bikes, and carts play a different game.

An overly rich mixture carries partially combusted and uncombusted oil and fuel into the exhaust. A proper mixture and load burns it up. Pretty simple.
Not running a trimmer wide open is operator error. The simple carbs on power equipment don't have enough tuning circuits to run clean at low rpm.

 

[North by Northwest]

An overly rich mixture carries partially combusted and uncombusted oil and fuel into the exhaust. A proper mixture and load burns it up. Pretty simple.
Not running a trimmer wide open is operator error. The simple carbs on power equipment don't have enough tuning circuits to run clean at low rpm.

Perfect explaination or annalogy of how operator error effects the overall performance & life cycle of a trimmer !

 

[ZeroJunk]

Perfect explaination or annalogy of how operator error effects the overall performance & life cycle of a trimmer !

Not error necessarily. Nobody is going to run a string trimmer wide open trimming around anything for the reasons explained earlier. Just like nobody is going to throttle a chainsaw just enough to get the chain to turn cutting a log.

 

[lone wolf]

Some run 25:1 mineral and their pistons and cylinders are mint after thousands of hours. Though that’s in Australia where the wood is hard and the weather is hot.

Don't forget, you as a user are breathing that oil into your lungs! Take that into consideration. I run 40 to 1 in everything here.

 

[North by Northwest]

Not error necessarily. Nobody is going to run a string trimmer wide open trimming around anything for the reasons explained earlier. Just like nobody is going to throttle a chainsaw just enough to get the chain to turn cutting a log.

All 2T engines are designed to run wot while under load , lugging the engine can cause overheating & other issues detrimental to engine & saw component life. It most definately is ok to feather the saw while limbing & hinge work , otherwise 3/4 to full throttle during felling & bucking . Yes trimmers usage varies , idling , low rpm trimming etc. thats why proper oil selection , mix ratio & proper fuel selection & tuning is paramount . I have ran trimmers for over 35 yrs all kinds of oil ratios & like Ben has stated have never experienced , carbon or spoonge ...ever . You must tune to the mix ratio & saw or trimmers intended usage wether its a 1967 Pioneer or a 2015 Husquarna 572 xp or 1980 1600 weed-eater !

 

[bwalker]

Not error necessarily. Nobody is going to run a string trimmer wide open trimming around anything for the reasons explained earlier. Just like nobody is going to throttle a chainsaw just enough to get the chain to turn cutting a log.

I always run my trimmer wide open. I also remove the lower part of the guard sonI can run the line longer, which loads the engine more.

 

[North by Northwest]

I always run my trimmer wide open. I also remove the lower part of the guard sonI can run the line longer, which loads the engine more.

Good points on the longer & in my case thicker or heavier guage string usage . I keep mine wicked up also ! However short term unloaded low rpm is fine . The jest of his issue is unknowledgible operators Ben that you & i along with numerous others have witnessed over the years . Can't mix gas & oil properly or tune a engine or sharpen a chain to save their 1st borns life ! Throw in ethanol laden gas all is just peachy right ?

 

[North by Northwest]

Don't forget, you as a user are breathing that oil into your lungs! Take that into consideration. I run 40 to 1 in everything here.

Thinkin some of his clientel are sniffing something else Wolfy !

 

[bwalker]

Good points on the longer & in my case thicker or heavier guage string usage . I keep mine wicked up also ! However short term unloaded rpm is fine . The jest of his issue is unknowledgible operators Ben that you & i along with numerous others have witnessed over the years . Can't mix gas & oil properly or tune a engine or sharpen a chain to save their 1st borns life ! Throw in ethanol laden gas all is just peachy right ?

Yes, and that's why electric is a good thing for these folks.
My neighbor for instance was astounded that my 20 some year old Stihl FS90 starts and runs fine every year. He told me he has never gotten more than three years out of a trimmer before it gave him issues.
FYI I run the heavy gauge square line as well. Mostly for durability which is a factor for me because I also use my trimmer to edge concrete with, which is hard on line.

 

[North by Northwest]

Yes, and that's why electric is a good thing for these folks.
My neighbor for instance was astounded that my 20 some year old Stihl FS90 starts and runs fine every year. He told me he has never gotten more than three years out of a trimmer before it gave him issues.
FYI I run the heavy gauge square line as well. Mostly for durability which is a factor for me because I also use my trimmer to edge concrete with, which is hard on line.

Birds of a feather brother ! I use square serrated gator line .080 guage with my Toro 14" Trimmer 8 yrs old , original spark plug . Might spring for a new one this yr . lol. Unfortunately your right , some people just are not mechanically inclined . We probably eventually will all be using elect. hand helds shortly , perhaps not in my life time but very likely within yours youngin

 

[ZeroJunk]

I always run my trimmer wide open. I also remove the lower part of the guard sonI can run the line longer, which loads the engine more.

I like that because I sell shafts and gear heads LOL

 

[bwalker]

I like that because I sell shafts and gear heads LOL

I've never replaced either. But always run machines with sold shafts and keep the gear heads greased..

 

[ZeroJunk]

I've never replaced either. But always run machines with sold shafts and keep the gear heads greased..

Well, you never really use anything. You are a creature of internet forums. I'm talking about guys who do this 8 to 10 hours a day in season for a living.

I keep at least 5 gear heads and 20 solid shafts and flexible shafts in stock all the time. And, probably three clutch housings with the bearings .

So yeah, I have done my yard for 30 years with a Robin. And, no problems. Duh.

 

[bwalker]

Well, you never really use anything. You are a creature of internet forums. I'm talking about guys who do this 8 to 10 hours a day in season for a living.

I keep at least 5 gear heads and 20 solid shafts and flexible shafts in stock all the time. And, probably three clutch housings with the bearings .

So yeah, I have done my yard for 30 years with a Robin. And, no problems. Duh.

My FS85 is over 20 years old and I got used from a friend that ran it for a couple years with his lawn care business. In addition I used it for 5 years in my own business clearing miles of Bush trails every year. It's all original save once crank seal and a coil. I don't remember for sure, but I may have replaced the sparkplug too when the coil crapped out. That's it..
You think it's a flex because you work on a bunch of junk, but I've actually run the stuff..alot.

 

[ZeroJunk]

My FS85 is over 20 years old and I got used from a friend that ran it for a couple years with his lawn care business. In addition I used it for 5 years in my own business clearing miles of Bush trails every year. It's all original save once crank seal and a coil. I don't remember for sure, but I may have replaced the sparkplug too when the coil crapped out. That's it..
You think it's a flex because you work on a bunch of junk, but I've actually run the stuff..alot.

Certainly not going to question you. But, if you bring a trimmer in with the string cutter gone claiming warranty I will fix it under warranty depending entirely on whether I like you or not. Stihl will deny it if I tell them.

 

[bwalker]

Certainly not going to question you. But, if you bring a trimmer in with the string cutter gone claiming warranty I will fix it under warranty depending entirely on whether I like you or not. Stihl will deny it if I tell them.

Mine hasn't had a warranty on it in decades. And if I did bring it in for warranty I would clip the string cutter back on..

 

[Squareground3691]

Yes, and that's why electric is a good thing for these folks.
My neighbor for instance was astounded that my 20 some year old Stihl FS90 starts and runs fine every year. He told me he has never gotten more than three years out of a trimmer before it gave him issues.
FYI I run the heavy gauge square line as well. Mostly for durability which is a factor for me because I also use my trimmer to edge concrete with, which is hard on line.

My FS80 is probably over 25 years old, just replaced carb last , still runs like a champ .

 

[bwalker]

My FS80 is probably over 25 years old, just replaced carb last , still runs like a champ .

Mines actually a FS85. Which is the solid shaft version of what you have.
I believe the FS90 is a 4mix engine.

 

[ZeroJunk]

Mine hasn't had a warranty on it in decades. And if I did bring it in for warranty I would clip the string cutter back on..

Well, if you have run the string long which certainly has it's advantages it will make the shaft round off faster and eventually wear the gears out in the head. I'm thinking the shafts are like $12 and take 30 seconds to swap. Gear head is about $70.

Much is a relative term, but if you have never replaced either you have not used it much in the scheme of things.

I wouldn't wear one out in a lifetime myself. But, I replace those parts for people who make a living with them every week.

I like the FS85's
best of all Stihl trimmers. Don't see them often anymore, maybe once every couple of weeks.
Even FS90's are dwindling. And, I liked them better than the FS91's or FS94's.

And, there is always a row of those solid white homeowner models every day I come in with some malady. Hasn't been run in a year or two and carb stopped up or easy start spring jerked apart as if somebody thinks pulling it harder is going to change how it works or something.

Well, it gives me something to do.

And, as far as the warranty deal goes Stihl has never turned down any claim that we have sent in since I have been there.

 

[North by Northwest]

Mines actually a FS85. Which is the solid shaft version of what you have.
I believe the FS90 is a 4mix engine.

Yes your correct Ben the FS 90 is the 4 mix engine spec'd for 50:1 2 cycle mix . I run Saber and its been fine along with a FS 110 brush cutter / power broom no problems with the valves or spoonge until you use Ultra , then as your well aware , all hell breaks loose brother !