Wrong.All 2 cycle engines should use 89 octane or better. Saw a collapsed piston from using 87 octane.
I feel your pain!! I have a Stihl FS 240 trimmer. I finally decided to experiment with starting other than the manual advised way. Sometimes I would not prime or choke and instead just pull the cord several times. Much of the time it would start. Sometimes after pulling several times I would press the gas/trigger all the way and start pulling and it would start. Didn't make much sense to me but there we are!! More recently, it has gone back to starting by priming, choking and pulling. I suppose there must be a mechanical reason but I sure can't figure it out. But then, I've always heard that Sthil was difficult to start!I have the ms251C Light 04 as you can see in the title it truly is a love-hate relationship I have with this chainsaw. If you can get it to start on the first few pulls it is a great saw if you can't it is the worst saw you can have. This saw is sold as an easy start and it is if you get it to fire in the first second or two if not put it away and get out the old saw. When I first got this saw I thought it was an operator error, but not anymore it is a case of crap or great. OK let's assume that it is me how do you get this thing to start without learning how to swear like a trooper? This saw must flood by just looking at it wrong, I really don't want to take off the cover each time I run into a starting problem to try and dry out the carb or throw Eather down the carb.
If you miss the poot and crank it again it will flood.
I can honestly say that the number of times I've started any of my saws any other way than dropping 'em could be counted on my fingers. Well Throwing is more like, I gotta heave my 440 magnum good and hard. never had any problems starting my 036; that saw is a dream. I even toss my little Echo I used to use for tree climbing when I still had calcium in my bones.And as mentioned drop starting will not work.
This is somewhat off-topic but related to the hard start problem. Compact engines usually have a smaller diameter starter cord pulley, which makes them harder to pull over due to having less leverage than a larger diameter pulley. I suspect that is what led to the easy start systems. I have a 40-year-old McCulloch chainsaw that has a larger diameter start pulley, and it is considerably easier to pull over than a similar capacity, but smaller, Husqvarna saw that I have. An old Poulan chainsaw that I replaced the fuel hoses on for a neighbor, was similar to the McCulloch, but like the McCulloch, it was a physically larger and heavier saw than the Husqvarna. Larger equipment, like push mowers, are often easier to pull over than a small saw, blower or trimmer, even though the engine displacement is greater. They are heavier and more stable, which counteracts the force applied to crank them, and the starter rope pulley is usually larger than that of compact handheld equipment.Well, after reading this I actually have to agree with the poster! Hey, Stihl should KNOW(!) after building saws for a century(?) that GUYS are pulling on saws-- not little girls. If the damn thing won't start, guys pull harder and faster too!
My own 2 cents: I have a Stihl FS 45 string trimmer, now it may have other problems making it hard to start, but top on my list is my WIFE cannot even pull the cord-- not enough strength at 72. I have to go out and buy a dang battery driven trimmer so she can trim weeds. On the other hand, her simple little Tecumseh rototiller, she can start no problem, every time. A bigger engine.
Now, back onto the subject. This same string trimmer is hard starting too. After reading suggestions above I will try the "not more than 4 pulls at Full choke" and "slow / easy pulls" before putting it up for sale on Craig's List. I just don't have time to putz with all the small engines sometimes. My 362, 462, and MS25C all start fine though.
Will have some effect ot starting, but also need to take into account that older saws ran a 7:1 or so compression ratio whereas the newer Stihls, Husqvarna, Dolmar/Makita run a 10:1 ratio. Which is the reason that call for 89 octane or higher fuel.This is somewhat off-topic but related to the hard start problem. Compact engines usually have a smaller diameter starter cord pulley, which makes them harder to pull over due to having less leverage than a larger diameter pulley. I suspect that is what led to the easy start systems. I have a 40-year-old McCulloch chainsaw that has a larger diameter start pulley, and it is considerably easier to pull over than a similar capacity, but smaller, Husqvarna saw that I have. An old Poulan chainsaw that I replaced the fuel hoses on for a neighbor, was similar to the McCulloch, but like the McCulloch, it was a physically larger and heavier saw than the Husqvarna. Larger equipment, like push mowers, are often easier to pull over than a small saw, blower or trimmer, even though the engine displacement is greater. They are heavier and more stable, which counteracts the force applied to crank them, and the starter rope pulley is usually larger than that of compact handheld equipment.