This is a thread re-direct that should be self-explanatory for those at all interested. Sorta needed its own heading for further discussion, imho.
It started out as a coupla blown up 310's and quickly evolved into a different discussion -- probably deserving of its own treatment since it would seem to apply to any recently manufactured products subject to the latest EPA regs, and the warranty coverage of those products (or lack thereof) if corrective measures are taken by the customer to keep from destroying his purchase under the new EPA rules -- with particular respect to using E10 based fuel mix.
So bring the experiences, dealer responses to your brand new blown up 310's because of ethanol based fuel mixes, corrective measures you have used to avert automatic disaster with your new saw, yada, yada.
I've encapsulated the basic essence of the E10 aspect of the previous thread for general review consumption for anyone else wanting to contribute.
We're scratching ours, too.
Woulda killed the warranty on the month old saw.
So what are these EPA purposes?
Then why do manufacturers build and tune em to blow up?
I'd say most would agree that the elders will run better for all the obvious reasons. But manufacturers building younger siblings destined to blow up given today's extremes in fuel quality just doesn't make sense to me.
Precisely. W - T - F? I'm taking it more as an assertion, basically understand it, don't necessarily disagree, but.....,
Hope you don't think I'm pickin' on you, Fog. Quite the contrary. I'm intrigued by your take on all of this and just want to learn more and hopefully acquire additional substantiation-- and mebbe use your approach to turn my 039 into a 660!!!
Any new takers on clarifying the subject for the masses?
Poge
It started out as a coupla blown up 310's and quickly evolved into a different discussion -- probably deserving of its own treatment since it would seem to apply to any recently manufactured products subject to the latest EPA regs, and the warranty coverage of those products (or lack thereof) if corrective measures are taken by the customer to keep from destroying his purchase under the new EPA rules -- with particular respect to using E10 based fuel mix.
So bring the experiences, dealer responses to your brand new blown up 310's because of ethanol based fuel mixes, corrective measures you have used to avert automatic disaster with your new saw, yada, yada.
I've encapsulated the basic essence of the E10 aspect of the previous thread for general review consumption for anyone else wanting to contribute.
I have a customer who has destroyed 2 310's. The piston and cyl.
are scored on the ex. side on both saws. I know this guy, and how he takes care of his
equipment, and it most likley isnt him. Same gas has been used in 2 other saws...90+
octane, minimal alcohol. Pressure and vac. tested, tight as a drum. No obstructions in
the muffler and fuel line, filter and carb is in good shape. One of the 310's was 15
months old and the other is about a month. He has been running Stihl oil, and when I
checked there was nothing but premix in the fuel tanks. I'm scratching my head, any
thoughts would be appreciated.
Jim
We're scratching ours, too.
Were the limiter caps removed, and saws tuned in
properly?
Woulda killed the warranty on the month old saw.
EPA blues. These are good saws that Stihl has had to
gradually strangle for EPA purposes.
So what are these EPA purposes?
Sounds like E10 gasoline. I have a 290 that had been running OK,
not great but OK since 2003. E10 was pushed in our area earlier this year and there were
a number of saws, including mine, that have the same problems as the ones you described.
The condition of my saw was the same as you described - no problems except for the
scoured cylinder.
Now, mine is running great after a new engine thanks to Fish. Tabs are gone off the caps
and it runs like it should, idles at 2,000 and 13,500 WOT (4 cycling and the ring not
seated). I did not have to change anything else on the engine except for the muffler.
Opening up the muffler makes a big difference in the amount of cylinder heat - which is
worse when you go to E10 gas. I did change the brand of oil and amount I use after
taking the engine apart and seeing how it is made, but that is another story - not
getting into one of those "oil war" threads...
A combination of the E10, with the "factory" settings and EPA muffler will fry a
290/310/390 that was already set on borderline lean (on a cool day) - which is what the
EPA mandated factory settings are (14.7:1 is "factory" fuel/air ratio and E10 changes
those settings to 15.2:1-15.3:1 with the extra oxygen in the alcohol).
So what mix works best (for you) with a modded saw running an E10 based fuel -- and why in your opinion?
Fog
I'm very interested in the source(s) of your data with
particular respect to the Stihl series in question relative to the ambient temperature
affect on borderline lean settings per mandatory EPA factory settings.
Poge
Pogo,
The fuel/air ratio numbers came from the EPA website under reformulated gasoline. These
are the numbers that Stihl, Husky and all the other manufacturers have to shoot for -
and the reason for the limiting tabs.
Fuel air ratios have always been at a specific temp and altitude - 70 degrees and sea
level. You can find that in any decent engine tuning book or book on making horsepower.
One of mine is "the Two Stroke Tuners Handbook". There are also a number of books on
drag racing engines that have information about air density, temp, and altitude. Those
are idealistic conditions where you make horse power, also why gas mileage is better at
night in Texas. When the air gets "warm" the settings change and so does the needle
settings. If it is set where it should be, a change in air will not really affect a
chainsaw enough to go lean. If a chainsaw has the EPA settings, then warm air will
definitely affect the engine. Add E10 and you need mine shaft weather.
A high performance two cycle will be affected by any weather changes. At a race I have
to adjust the needle on my engine each run through out the day as the weather changes.
Those engines are on the ragged edge and we notice any change in weather. There are also
those days that the weather sucks and you just can't make as much power. Which is why I
would never set a chainsaw with a tach to factory rpms- could be a bad air day and you
would fry the engine trying to hit 14,000 when the best it can get is 13,500. We carry a
"weather station" and know what the conditions are and if the air is bad, then you just
live with it - everybody is running the same air. But, even with the engine dialed on
kill every run, we never run them as lean as the numbers the EPA mandates for everyday
usage on chainsaws.
Fog
Then why do manufacturers build and tune em to blow up?
This is probably true. It does not sound like the
paragon of saw knowledge and experience was running these 310s. I sure didn't mean to
knock the 290/310/390, I actually think they are very good saws and have held up
incredibly well for a homeonwer-type saw.. heck for ANY saw! But I do think the fact
remains that, tuned as they are today coming out of the factory, they simply don't run
like their older brothers and sisters. If you go run a brand new 290 against an older
one I think you will see what I mean. Compare the outlets in the muffler (for instance)
and you'll find that they just don't breathe as well. The slightly modded 290/310/390
is a strong running. robust saw. The new ones are anemic in comparison. The good news
is that with a little fiddling, you can have a new one that runs like an older
one.
I'd say most would agree that the elders will run better for all the obvious reasons. But manufacturers building younger siblings destined to blow up given today's extremes in fuel quality just doesn't make sense to me.
Ok, I have a year old MS390 that I've done nothing to "mod"
wise because I'm happy w/ it. Some of you actually contend that I'm risking damage to
my 390 by NOT "modding" it because of the way the EPA knobgobblers have regulated the
tunings? Wtf? I never use the ethanol gas.
Precisely. W - T - F? I'm taking it more as an assertion, basically understand it, don't necessarily disagree, but.....,
Poge,
I guess I should have said that those numbers apply to any engine (2 cycle or 4 cycle),
but the thread was about the 310 and I was thinking about the 290/310/390 series. I got
a bit po'ed when my saw died and started doing some reading about the EPA "stuff" and
found that info. My background causes me to do research on various technical topics. And
racing for over 30 years leads you down a lot of paths on engines, carbs, exhaust, and
fuel/oil. Sometimes you forget that not everyone does those things.
Before I ever ran my new 361, I dumped the gas that the dealer had put in it and
replaced the caps with some X-Acto brand and set the carb. I use a whole different fuel
mix than they do and don't care for the EPA settings. I checked the settings before I
changed them and my new saw would have been dead in no time. With E10 being the law of
the land, they really need to change the factory settings or see a lot more dead saws.
In talking to a number of dealers in the Houston area, there are already a number of
dead saws from the E10 in our area.
My saw problems have not been in vein though, my 290 is now better than it was new and
makes more power than a stock 390. I am even looking around for a 390 cylinder assembly
to see what I can get out of the saw. My racing partner an I have been having fun with
these little engines and I keep telling him I need a chrome liner for it - we'll see.
Fog
Hope you don't think I'm pickin' on you, Fog. Quite the contrary. I'm intrigued by your take on all of this and just want to learn more and hopefully acquire additional substantiation-- and mebbe use your approach to turn my 039 into a 660!!!
Any new takers on clarifying the subject for the masses?
Poge
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