Smitty Smithsonite
ArboristSite Operative
I had a Huskee push mower once years ago. Used to love to blow oil straight out the exhaust. Was at the proper level, too. Great for the flower beds. 
Is Stihl 4Mix to be avoided, looking at strimmers
- Thread starter Fatherwheels
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I had a Huskee push mower once years ago. Used to love to blow oil straight out the exhaust. Was at the proper level, too. Great for the flower beds.
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That's an easy fix, just stop adding oil! It'll find its happy spot....
Sure way to keep the aphids off the roses!I had a Huskee push mower once years ago. Used to love to blow oil straight out the exhaust. Was at the proper level, too. Great for the flower beds.
View attachment 1009352
Smitty Smithsonite
ArboristSite Operative
Indeed!
FS80 kicks a$$ best engine stihl ever made / 4 mix sucks will never own one
Dunno I have 4) 4mix from 90's to 130's generally like em all over 2 strokes. Still searching for some better answers re the H/L speed mix screw restrictors and settings.
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user 188535
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My 131 can handle a summer of brush mowing just fine. Bike handles are the best though.
I agree. I like the low rpm grunt. Internals look as clean as after the first summer I bought it. 2-3 pulls starts right up and purrs at idle. Not heavy usage by some standards. I avg only 3-4 gallons mix per season. At this rate it should last me a lifetime.
salvagedrover
ArboristSite Lurker
It’s amazing how many accusations are voiced without any back-story or evidence. I buy 4-mix machines from municipalities all the time to fix and sell. I can’t really say out of dozens and dozens of FS90Rs, BR600s, and FS130s, or 131Rs that I’ve ever had an engine come in that was damaged or failed because of something other than a lack of maintenance.
I got MANY, almost all machines in for lack of maintenance, or perhaps lack of proper training and understanding of how the 4-mix system is just as easy as any other engine to maintain. In fact, aside from some connecting rod to wrist pin issues on early FS91R trimmers (which are actually the exact same part number as an FS90R crank, so that tells me it’s a bad wrist pin design and why it was superseded), I’ve never seen anything aside from being bounced out of a truck on the road, or ran over or run without a guard that damaged these.
Most “mechanics” without gloves and hearing protection are using “if it ain’t broke, don’t fix it” from a bygone era where things were made to last, before companies realized, much like the Maytag commercials, they couldn’t sell more units if the old ones didn’t break. That’s not to say they’re built poorly or with flawed designs, but they make these machines run so well on very specific conditions, much like race cars or planes, so that when they’re NOT maintained, they fail. Lighter materials, more plastic, ways to keep generating more and more profit without having to focus on quality or longevity, makes them profit while still putting out a quality-performing product. But, mechanics will still use carburetor cleaner and a brush to clean plugs when a replacement is just common sense. They still use shop air to blow out pleated-paper air filters as if they’re made of the same materials from 30+ years ago. They run trimmers without guards, they make the wrong mix so that there is too much oil figuring that more is safer or better, so that the mixture is too oil-laden, too heavy, doesn’t atomize with the fuel, and basically pools at the bottom of the filter housing, while the raw fuel separates and runs the machine lean. They spill fuel all around the engines and don’t bother to clean them, so it collects debris that gets into moving parts and acts like lapping compound to wear them out. They don’t clean around engine seals, so those go bad, ingesting debris to ruin bearings. The don’t clean off the build up of crap all around the engines, which builds and builds, effectively acting as insulation around an air-cooled engine, causing them to cook. They don’t do a simple valve adjustment, even as little as once a YEAR, and wonder why the valves burn up or drop or wear out the plastic can wheel DESIGNED TO BE PLASTIC, so it sacrifices itself rather than your expensive engine, (they’re wearable items, just like brake pads).
Companies hire mechanics, but don’t hire good ones. They don’t train them, they don’t send them to manufacturer update schools, repair service schools, nothing. They often don’t provide specialized tools, and the mechanics don’t want to lose their jobs, so they have to blame the machine when they are not educated as to how they’re properly repaired or maintained, I’ve seen it countless times.
There is nothing communist about wanting cleaner air, less triple-digit temperatures, less floods, calmer winters, I don’t feel WE’RE the ones who need to not drive larger trucks or run less 2-stroke equipment, turn off the water when we’re doing our by-weekly toothbrushing, but there is nothing wrong with doing it because it’s not a bad thing to do and is just lazy not doing it.
Btw, if anyone was wondering, I’m a STIHL Gold level technician, I have worked at almost a dozen shops from 2003, ran two, owned a mobile repair business and got a news interview about my service which is posted on YouTube, and personally own extremely expensive commercial mower hydraulic system testing tools, as well as fuel injection repair tech for STIHL, Husqvarna, and KOHLER. Plus I’m a great lover and a pretty decent cook. So I might know what I’m talking about, but hey, everyone is entitled to their opinions, nobody is forced to follow someone else’s advice, regardless of their training or experience, because afterall, this is america...
I got MANY, almost all machines in for lack of maintenance, or perhaps lack of proper training and understanding of how the 4-mix system is just as easy as any other engine to maintain. In fact, aside from some connecting rod to wrist pin issues on early FS91R trimmers (which are actually the exact same part number as an FS90R crank, so that tells me it’s a bad wrist pin design and why it was superseded), I’ve never seen anything aside from being bounced out of a truck on the road, or ran over or run without a guard that damaged these.
Most “mechanics” without gloves and hearing protection are using “if it ain’t broke, don’t fix it” from a bygone era where things were made to last, before companies realized, much like the Maytag commercials, they couldn’t sell more units if the old ones didn’t break. That’s not to say they’re built poorly or with flawed designs, but they make these machines run so well on very specific conditions, much like race cars or planes, so that when they’re NOT maintained, they fail. Lighter materials, more plastic, ways to keep generating more and more profit without having to focus on quality or longevity, makes them profit while still putting out a quality-performing product. But, mechanics will still use carburetor cleaner and a brush to clean plugs when a replacement is just common sense. They still use shop air to blow out pleated-paper air filters as if they’re made of the same materials from 30+ years ago. They run trimmers without guards, they make the wrong mix so that there is too much oil figuring that more is safer or better, so that the mixture is too oil-laden, too heavy, doesn’t atomize with the fuel, and basically pools at the bottom of the filter housing, while the raw fuel separates and runs the machine lean. They spill fuel all around the engines and don’t bother to clean them, so it collects debris that gets into moving parts and acts like lapping compound to wear them out. They don’t clean around engine seals, so those go bad, ingesting debris to ruin bearings. The don’t clean off the build up of crap all around the engines, which builds and builds, effectively acting as insulation around an air-cooled engine, causing them to cook. They don’t do a simple valve adjustment, even as little as once a YEAR, and wonder why the valves burn up or drop or wear out the plastic can wheel DESIGNED TO BE PLASTIC, so it sacrifices itself rather than your expensive engine, (they’re wearable items, just like brake pads).
Companies hire mechanics, but don’t hire good ones. They don’t train them, they don’t send them to manufacturer update schools, repair service schools, nothing. They often don’t provide specialized tools, and the mechanics don’t want to lose their jobs, so they have to blame the machine when they are not educated as to how they’re properly repaired or maintained, I’ve seen it countless times.
There is nothing communist about wanting cleaner air, less triple-digit temperatures, less floods, calmer winters, I don’t feel WE’RE the ones who need to not drive larger trucks or run less 2-stroke equipment, turn off the water when we’re doing our by-weekly toothbrushing, but there is nothing wrong with doing it because it’s not a bad thing to do and is just lazy not doing it.
Btw, if anyone was wondering, I’m a STIHL Gold level technician, I have worked at almost a dozen shops from 2003, ran two, owned a mobile repair business and got a news interview about my service which is posted on YouTube, and personally own extremely expensive commercial mower hydraulic system testing tools, as well as fuel injection repair tech for STIHL, Husqvarna, and KOHLER. Plus I’m a great lover and a pretty decent cook. So I might know what I’m talking about, but hey, everyone is entitled to their opinions, nobody is forced to follow someone else’s advice, regardless of their training or experience, because afterall, this is america...
@salvagedrover you’ve been here for 15 years with 6 post and you write a book replying to a year old thread? That part is kinda funny but…What the heck is with the weird cook and lover line?
TOTALCHAOS69
ArboristSite Lurker
Seemed like a brief resume of some weird sort … 
Yes, but he/she is a great lover
Seemed like a brief resume of some weird sort …
PS I'm a home owner use 4mix fan boy, owning 4.
Because it's a Stihl it's not maint friendly, takes more work than it should to get at the valves to set them. I curb snatched some cheapo brand "4mix" strimmer, free cuz it wouldn't start, was amazed; remove two screws to set the valves, yeah all it needed. Running great when I sold it.
Stihl 4mix I own;
Bought the pole saw new, (set the valves after a couple years of light use)
3 strimmers
One very nice looking, used, cheap, wouldn't start (set the valves) runs great.
One like new, pretty sure I bought it from the owner's crackhead son off CL. After a couple years use I set the valves.
One was a beat to crap unit from a lawn care service that sold all his old equipment cheap. Finally messed with it, runs great after (yeah you guessed it)
Summary;
When 4mix get hard to start and generally grumpy, I set the valves. Otherwise maint is same as any gas equip.
They use about half the fuel of 2strokes,
are quieter
idle much nicer, no raxxing needed.
EASY to start nearly immediately run well and idle even after sitting for a year.
Are higher torque at lower RPM than the 2 strokes, you don't have to keep the throttle pinned WFO, further reducing fuel use, noise, and string damage to trees, house trim etc.
Will probably disappear as battery units gain market share.
Smitty Smithsonite
ArboristSite Operative
I can't fathom how anyone could buy a 4-mix when there are MUCH better alternatives. 2-strokes are lighter, more powerful for their size/weight, cheaper, cheaper to maintain, WAY less moving parts, and require NONE of the maintenance you need to do with a 4-stroke. When tuned right, a 2-stroke will ALWAYS start much easier / faster than any 4-stroke. Plus, you STILL have to premix it! Zero benefits.
Been working on small engines for 30 years. Just calling it like I see it.
Been working on small engines for 30 years. Just calling it like I see it.
But Smitty, didn't you read the last 3 pages explaining why they weren't as bad as everyone says?
OK the speed of a 4 mix head is equal to a 2 stroke. Due to the 4 stroke having more torque available, the head can be geared for more speed. Engine rpm does not make for faster head speed.
4mix is almost exclusive for pro landscapers in this area. At least 50 per cent of home owners. The two strokes are bought in the lower end (FS38 through FS56).
TOTALCHAOS69
ArboristSite Lurker
And someone looking for a position as a cook or lover! Don’t forget that!
I own a 94 and. 131r. I do like the weight of the 94 etter, who wouldn't. The 131r is a 4mix and I run it on 40:1 just like the 94. Never had a problem with it and the extra power for pruning is a game changer. It has a different feel running for sure but I have only had to adjust the valves 1 time.
The 94ce is a great product too and has earned it's place in the shed. Lightweight and bicycle handles for those long brush cutting sessions
makes it a great tool for those days when I dont need maximum overdrive.
I have no reservations about using either of the motors.
The 94ce is a great product too and has earned it's place in the shed. Lightweight and bicycle handles for those long brush cutting sessions
makes it a great tool for those days when I dont need maximum overdrive.
I have no reservations about using either of the motors.
