OK - when I get the saw out I pull it through once or twice with the
choke on, and the ignition off so it won't tear my arm off - then turn
on the ignition and give it a couple good sharp pulls - Usually
running on the second pull with the ignition on.. Usually barks at me
on the first "powered on" pull. - knock the choke in one notch and
pull again. It either starts or tears the rope out of my hand. I don;t
know if the saw is stock or not - I've only owned it for about 25
additive to increase octane to help prevent engine knock.
Vehicles have knock sensors that listen for knock and will retard the
ignition timing to help prevent engine knock with cheaper grades of
fuel. Premium fuel typically helps to prevent knock and the ignition
timing will electronically advance for better power and gas mileage.
In the old days when you set the ignition timing manually the engines
would truly run hotter if you advanced the timing too much.
Relatively modern engines these days monitor all of the engine functions
and make adjustments accordingly.
If you chain saw has an electronic ignition and a knock sensor the
timing could be advancing with premium fuel and running hotter. Or you
could simply be getting a more complete burn with the better fuel and
naturally running a bit hotter.
I don't envision a computer controlled injected 2 stroke chain saw in
the near future - the extra weight and the durability concerns make
it somewhat unlikely in my lifetime for any but the largest
The day of the gasoline consumer saw is likely coming close to an end
with new electric saw technology advancing very quickly.
trunk with a 10 inch electric on a pole. Line powered - not battery -
in less ths 3 hours. The tree was higher than my 2 story house. I
used the electric pole saw because there was no way I was taking the
remington up into the tree. I limbed it from a 12 foot stepladder with
the pole saw completely extended.
After I had it down to the 4 or 5 foot stump I pulled out the
remington, the noticed there was a tree service truck just finishing
up down the street so I asked them how much to finish the stump and
chew up all the branches so I didn't need to haul it to the dump.
Less than an hour later there was nothing left but some leaves and
twigs. (and the stump chunks I had other plans for)
The higher end Stihl and Husqvarna professional saws have engine management
systems available that electronically control the ignition timing and fuel
metering... Both claim to compensate for different fuels, altitude,
humidity, temperature and clogged air filters.
Stihl's is called M-Tronic and Husqvarna's is called Autotune.
That said, the average homeowner or farmer probably isn't going to buy one
of those professional saws... they are costly and excessively powerful for
what mere mortals need in a chainsaw. The guys making a living in the woods
or doing serious tree work are more likely to spend the big bucks...
Don't forget the tool junkies. "This thing has electric start,
SparkAdvance(TM) (tm)* that automatically fires the spark before cylinder
reaches TDC, TriggerValves (tm) that restrict fuel flow when you're not
running full speed, and OxoInject (tm) for mixing fresh air with the fuel
for better burn!"
* (For marketing reasons "SparkAdvance(TM)" is the trademarked term.)
The manual with my saw recommends a minimum of 89 octane... I use ethanol
free premium gas along with synthetic 2 cycle oil (STIHL HP Ultra) that has
fuel stabilizers. In the past year or so one of the chain convenience stores
started carrying ethanol free premium gas and they are adding store
locations steadily over time--I've got one 7/10ths of a mile from my house
now. I started using this mix in all my Stihl 2 stroke equipment (string
trimmer, hedge clipper, chainsaw), and the gas in my mower, and everything
I would expect your saw to run cooler, and better, with the premium fuel as
compared to say 87 octane based on my saw's manual:
"Use mid-grade unleaded gasoline with a minimum octane rating of 89 and no
more than 10% ethanol content."
"Fuel with a lower octane rating may increase engine temperatures. This, in
turn, increases the risk of piston seizure and damage to the engine."
On Sun, 27 Dec 2015 23:50:42 -0500, "John Grossbohlin"
equipment. For the small amount of fuel I put through them in a year,
the difference in cost is a non-issue, particularly considering the
possible costs of the alternatives. A screwed up carb or a scuffed
piston or siezed engine is too costly to consider trying to save the
7 cents a liter or whatever.
I do the same. I have a 4 cycle mini-rototiller with a Honda mini engine. It
has been a problem from new, had it serviced and not much better. It was
hard to start and would stall after running a few minutes, and then only run
a minute or so after starting hot. This was with regular 87 gas. I also have
a Honda weed wacker with a mini 4 stroke engine that runs fine with regular
Switched all my small engines to Shell premium, they run great and even the
difficult mini-rototiller Honda now runs properly with only a change of fuel
The added cost of premium is insignificant compared to frequent servicing
required when they don't run properly. By the way, I have a Honda
self-propelled walk behind mower that is now over 25 years old and has never
needed service other than oil changes. It starts on the first pull.
Aside from the
fact that that wouldn't be legal or smart in many
jurisdictions (that's 100LL, and I'll allow you
to research what the "LL" stands for, and the restrictions
on the use of 100LL nationwide, or the efforts to phase it out).
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