The dreaded chainsaws oil thread

[windthrown]

OK, the Which chainsaw premix oil should I use? thread, dedicated to Gary on Whidby Island in Washington State.

OK, for chainsaws, forget about using TC-W3 oil. If you are using that type of oil in your chainsaws, stop. TCW3 is a standard developed by the National Marine Manufacturers Association, and designed for water cooled engines that run at low RPMs. It will work in a pinch in chainsaws, and usually keep them from scoring and seizing. But long term they are not good for using in them, as they are ashless and are designed for cooler running engines. Also many 2 stroke oils out there claim to be for any 2 stroke engines, marine or land use. Most of these are TCW rated. Avoid using them in chainsaws. TCW rated two stroke oils are the most common because the two stroke marine engine oil demand dwarfs the two stroke air-cooled engine demand by about ten to one.

An alternative standard developed for high reving air cooled 2 stroke engines was originally created by the American Petroleum Institute(API). API only has one standard for 2 stroke oil, which is API TC. This standard is no longer reviewed and it has not been updatd since 1993, but many companies still use it for specifications and it still remains in effect. It is roughly equivalent to JACO FB and ISO-L-EGB, which are defined below. So the most basic thing to look for when buying oil for your chainsaw is a TC rating, and not a TCW rating.

For land use equipment like motorcycles and other small 2 stroke engines, and to reduce exhaust smoke and improved cleanliness and lubrication in motors in Japan and Asia, the JASO (Japanese Automobile Standards Organization) two-stroke oil standards were developed. The levels of these standards are (from low to high): JASO FA, FB, FC and FD. FA was the original specification established regulating lubricity, detergency (self cleaning capacity), initial torque, exhaust smoke and exhaust system blocking. JASO FB has increased lubricity and detergency, reduced exhaust smoke and exhaust system blocking requirements over FA. JASO FC has the same lubricity and initial torque requirements as FB, but has far higher detergency, exhaust smoke and exhaust system blocking requirements over FB.

In Europe, engine manufacturers demanded greater detergency and improved spark plug fouling than was provided by JASO FC standard quality oils. This led to the development of the Global ISO-EGD standard (ISO is the International Standards Organization). As a result of that, the JASO FD standard was added as an equivalent. JASO FD is same as FC with a far higher detergency requirement. Basically, these are the equivalences between the JASO and ISO standards:

ISO-L-EGB – same tests and requirements as JASO FB (and similar to API TC)
ISO-L-EGC – same tests with slightly higher detergency requirements (piston varnish) as JASO FC
ISO-L-EGD – same tests and requirements as JASO FD

Note also that in the US at least, there are laws stating that any equipment manufacturer cannot insist that you use only their oil to keep a chainsaw warantee valid. According to the Moss-Magnuson Warranty Act, it is illegal for any manufacturer to require the exclusive in the United States use of their private label product to keep their warranty valid. If a manufacturer indicates only their private label brand will satisfy warranty requirements, they must do one of two things. Obtain written approval from the Federal Trade Commission that no other product except their brand will work (currently, no manufacturer has done so) or they must make the product available to you at no cost. Also they cannot prove the type of oil that you use, nor the ratio of oil that you use in your saw. However, they typically say that you should use their own brand, or a higher rate of another brand (older Stihl saw manuals that I have recommend a 25:1 ratio of 'other' brand oils, but the newer ones say use 50:1 Stihl or other high quality branded oil).

[windthrown]

OK, so where do I get oil for my chainsaw?

If you go to your local Stop-N-Rob store or gas station, you are apt to find a small section of motor oil. Maybe in there will be one or two types of two stroke oils in small bottles ready to dump into a one gallon tank. If you look at the labels, they typically say what the oil was designed for. If it says TCW put it down. That is outboard motor oil. Next to it may be a similar bottle that says it is multi-purpose two stroke oil, good for outboard engines, chainsaws and motorcycles, but there will be no ratings at listed on it. Again, put the bottle down and step away from the shelf. You have struck out looking for chainsaw oil at that location.

So now what? You can go to the chainsaw shops, and they will typically have several types of two stroke oils. What you want are the better rated oils. Some brands are not JASO or ISO tested and rated though, as it costs a lot of money to certify oil. Some of these are good quality oil and they would qualify for JASO rating. I would ask you though, why would you buy an oil that was not tested and rated, when you can buy oils that have been tested and rated? Some companies like Stihl also have different types of oil. They have dyno oil (petroleum base), synthetic-dyno blended oils, and 100% synthetic oils. Now, I cannot tell you what the exact difference is between 100% dyno and 100% synthetic oil, but I can tell you that 100% synthetic oil runs better and is better for your saw. It does cost more, but it is worth it. Also some chainsaw companies brand their own premix oils. Stihl oil is confusing. Last I looked, their 100% synthetic oil was FB rated, and the synthetic-dyno blend was FC rated, and the standard stuff was not rated at all. Husky also sells oil, and they have similar ratings. I tend not to buy these types of oil, mainly becasue of the cost. If you buy premix oil at a chainsaw shop, you will generally pay a higher premium for the same or lesser quality oil than you can buy elsewhere.

So where is that? You ask... Used to be that auto parts stores had good chainsaw premix oil. I used to run Castrol 2T two-stroke dyno oil. It runs OK, and your chainsaw engine will not burn up on you if you use it. You can still buy it at just about any auto parts store in the US. However, it is only rated at JASO FB, and it smokes a lot. It also leaves deposits in your engine, and clogs up muffler screens. It is better than the non-rated Brand-X stuff, and certainly better than TCW stuff. But what is better? It used to be that Mobil 1 2T was also available at a lot of auto parts stores in the US. That was rated JASO FC and it was cheap. About $8 a quart. The only drawback was that it was clear, and some people had a hard time knowing if their chainsaw gas was mixed with oil or not (Castrol 2T has a heavy blue dye in it, and it is easy to tell if the gas was premixed with that oil or not). Unfortunately, for some reason that I still have yet to find out, Mobil decided to stop marketing Mobil 1 2T in the US. No more can be found on the shelves here. Some cases float up on Ebay and Craigslist now and then. But shipping oil is expensive, and they are getting old. Chainsaw oil has a shelf life of about 2 years, maybe 3 if it is stored right. I hear that that stuff can still be bought in Oz, so you guys are lucky. Its 'cheap' good quality chainsaw oil.

So... now what? Well, that leaves two places to find good quality chainsaw oil. The first is your trusty Home Depot store. They are all over the US. They tend to have only a few types of oil though, and some are no-brand labels and non-rated. Avoid those. They also sell Echo chainsaw oil, which is pretty good stuff. Echo has JASO FC rated oil, and Echo Power Blend is JASO FD rated oil. Its good stuff, but they typically only sell it in small bottles so it is more expensive to run. The other palce to get good chainsaw oil are the motorcycle shops. Yeeeeeesssssss.... the motorcycle shops here have a lot of types of oil. Many motorcycles are still designed with two stroke engines, and they share the same heat and running conditions as chainsaws do. Its amazing how many oils that motorcycle shops have, really. They have over 100 types at the store that I get my chainsaw oil at now. What you want is a good 100% synthetic two stroke oil, JASO FC or FD rated. Most of the bottles there will have ratings on them. Some do not, like Yamaha (Yamalube 2T is suppoed to be rated JASO FC though) and Honda oil. The prices vary a lot too. Klotz and RedMax are really expensive. Over $100 a gallon here. They are both rated FD though. I buy Elf 2T 100% synthetic myself. Used to be $10 a liter. Now its $12 a liter. Still worth it, and cheaper than Stihl Ultra. They also have Motul 700 2T which is good stuff, rated FC, but that is more expensive. Elf and Motul also have FD rated oils, as do a lot of other brands. Some have FB rated oils as well.

If nothing else, I hope to pound into your heads that you need to read the labels on oil bottles. There are huge differences in two stroke oils out there, and as I said above, outboard motor oils outsell chainsaw type oils by about 10:1.

[Steve Tipton]

Thanks for that Scott.
I have used Castrol 2T for many yeaqrs without a problem.
Steve

[hddnis]

Eh, I don't dread these threads too much. I like seeing what other people use and why. As long as it don't get too nasty and not too much name calling.

We used to run Echo dino oil, that would be about twenty years ago. It was just easiest to put a six pack of mix bottles on each truck that was already measured for a 2.5gal can. Even with multiple crews and trucks we never had a batch of straight fuel make it through to damage stuff. The credit for that goes to my men, they are careful and have heads on their shoulders.

Only problem with the old Echo stuff was that it smoked and carboned up a machine in no time. The mufflers were always greasy and the spark screens needed cleaning all the time.

When the Stihl HP stuff came out we switched to that, partly because we switched to a Stihl dealer away from the Echo dealer we had been with for years. HP was better, ran a little cleaner and we had no complaints with it either.

Then Stihl HP Ultra came out and when it started getting good reviews we switched to using it. Bit of sticker shock at first so in the beginning I tried to only run it in the chainsaws. It was soon very clear that it was better stuff all around and so now we use it in everything. The spark screen cleaning has gone away. I've yet to need to open up an engine to clean out the carbon running that stuff. Some of the saws were due for a carbon clean-out when we switched and they have cleaned themselves up without damage.

At first I bought it by the case and then once we had plenty of the 2.5gal mix bottles I started buying it by the gallon. Local dealer here sells it to me for $72 a gal. I know it is a chunk of change, but it works and I hate fixing something that isn't broke.

I've been meaning to give some of the other less expensive options a try, because burning a gallon of the mix oil alone in a week gets spendy. Stihl dealer wants me to buy it in five gallon buckets or IIRC a 25 mini drum. I'm waiting for him to tell me what the savings will be.

That's all I can think of to add at this point. More of a story than technical information.


Mr. HE

[Done it]

Castrol 2T for me as well, for a long time.

[Eric Frei]

I use Stihl.

[rick]

Originally Posted by Ekka

I use Stihl.

Which is Castrol here (and Europe)

Is the Stihl HP Ultra available here ? If it was, I'm sure it'd be worth a bomb anyway. (I wonder if that turn of phrase will raise a flag at ASIO ? )

There are so many really good two stroke oils available, particularly synthetics, but most around here use good ol' Castrol 2T too.

BTW, here's the TDS for 2T http://www.tds.castrol.com.au/pdf%5C...25_2008_03.pdf

[Willard Holmen]

Stihl Premium is Castrol Super 2 Stroke here in Canada too. Stihl Ultra full syn here is pricey. My Stihl dealer charged me $30 Cdn for 6- 200ml bottles [6pack].
Willard

[rick]

Oil's a bit dearer here, I'll price up some 2T today from the local garage, but I use Motul 8002T OR which sets me back A$30/litre. Silkolene Pro 2 SX, another ester synthetic race oil is a touch cheaper at SuperCrap Auto's, but my Motul dealer (Husky/Shinny/Echo/Honda dealer) is 30km away, the nearest SuperCrap store is 100km. I used Castrol TTS (now Power 1 Racing TTS) for years with good results and paid around $27/litre.
Power 1 racing TTS is now JASO FD rated, but I wanted a slightly heavier (more viscous) oil for the 7900 and all the JASO FC/FD oils are around 7-9 cSt @100*C (roughly SAE 20) as they have added solvents to aid in mixing so they are thin enough for injector use, (some two stroke scooters use a separate tank to hold the oil, and it's precisely injected into the air stream) whereas the pure race oils are anywhere from 13 cSt to 20 cSt (SAE 40 to SAE 50).
We still have Mobil 1 Racing 2T here too.
Motul, Silkolene, Motorex, Elf, Agip Mobil, Castrol, Redline, etc all make excellent synthetic two stroke lubes that are available from bike shops.

Diverging a little onto Amsoils claim that their Pro Sabre ATP oil can be used successfully at mix ratios as lean as 100:1, one of the fella's on AS hypothesised that Amsoil Sabre worked at 100:1 as it's flash point was higher than other oils, here's my response.

Originally Posted by Adirondack

My impression was that Amsoil had been tested and ran the best at that ratio. I called them. They said they had used it in Lawn boys at 300:1 and had no issues. My question:

No, testing at 100:1 or 300:1 doesn't mean the machine made more power (ran better) at that ratio, it just means that it ran and didn't lunch itself, a big difference.

This is my theory. Most oil from other Mfrs. mixes would have a lower flash point and would burn a bit. This would add to the combustion energy. I notice in Amsoil pro mo material their oil does not burn off at working temp. Well if it does not burn it would not smoke and more oil would be left to lubricate the engine. This would explain less smoke and better lubrication at higher mix ratios. I wonder if this is correct?

No. Just compare flash points (and I've listed a heap in the past)

Amsoil Sabre ATP 114*C (Not JASO licensed)
Stihl HP Ultra 222*C (JASO FB, Castrol Europe/Omni lubricants US)
Castrol Power 1 Racing TTS 76*C (Australian blend, JASO FD license)
Castrol Power RS TTS 70*C (US blend, JASO FD license)
Castrol R2 Racing Bike 87*C (Australian blend, JASO FC license)
Castrol A747 274*C (GP racing bike oil, castor/synthetic blend)
Castrol XR77 223*C (Current GP racing bike oil, full ester synthetic blend, replaces A747 in extreme use)
Dolmar synthetic 2 stroke oil 99*C (US Blend, Spectrum Lubricants)
Elf HTX 909 270*C (synthetic/castor blend, kart engines, up to 25,000RPM)
Elf HTX 976 208* (synthetic, GP bike blend)
Husky XP oil 102*C (US blend, Spectrum Lubricants)
Klotz R50 204*C (synthetic)
Klotz Super Techniplate 238*C (syn/20% castor blend)
Mqaxima Castor 927 216*C (castor/synthetic blend)
Mobil 1 Racing 2T 110*C (Australian spec, JASO FC license)
Motul 710 88*C (JASO FD)
Motul 800 2T Off Road 252*C (GP MX blend)
Motul 88 2T Road 274*C (GP road bike blend)
Redline Racing 103*C
Redline Smokeless 82*C (equivalent to Ams Sabre, for chainsaw/OPE use)
Silkolene Pro 2 210*C

The JASO FC/FD oils generally have lower flash points to minimise smoke and meet the cleanliness requirements of the JASO licensing (and Sabre isn't licensed)
The race specific oils have pretty high flash points, and yet the full syns have minimal smoke anyway, as a few fella's have noted above.
In my case I use Motul 800 2T OR @ 40:1 and note little to no smoke or odour in use.

You need oil for ring seal, as well as bearing protection and piston skirt scuff protection.
The more oil, the better the ring seal (and skirt scuff protection). To get piston skirts to survive at leaner than 50:1 ratios that the manufacturers have designed for, the blender needs to load the oil with greater amounts of Anti-wear (AW) and Extreme Pressure (EP) additives and it will work, but what about ring seal ?
Dyno testing has proven that fatter (richer) oil/fuel ratios make more power and it's all down to sealing the combustion chamber during the firing/combustion process. Probably doesn't matter in a little strimmer, but it's a big deal in bikes/karts and a few people that run saws.

Chainsaws develop minimal BMEP (brake mean effective pressure) compared to other high performance two strokes. This is just a fancy engineering term for less specific power than kart and GP bike engines, which are developing over 400BHP/litre these days. As a consequence HP karts still use around 16:1 mix ratios to prevent seizing.
The interesting thing is that the oil companies often recommend changing to their racing oils from their high performance synthetics at around 14,000 RPM. Saws also cop a caning in terms of temps as they often have their fins blocked with chips and dust, so to my mind why skimp on mix ratio ? 32 to 50:1 is cheap insurance IMO.

Basically other oils must be used at 50:1 because some oil is being burned and less is left for lubrication.
Thanks in advance for the help.

I think I've put forward my thoughts above
__________________

[windthrown]

Originally Posted by hddnis

At first I bought it by the case and then once we had plenty of the 2.5gal mix bottles I started buying it by the gallon. Local dealer here sells it to me for $72 a gal. I know it is a chunk of change, but it works and I hate fixing something that isn't broke.

(snip)

Mr. HE

Seems like you are spending a lot more money than you need to on premix though. I bet you could cut a deal with a motorcycle shop and get Motil or Elf for a lot less. I pay $12 a liter for Elf 2T... that is $45.42 a gallon. 37% cheaper. Seems like 'a fix' would be worth it, for the bottom line.

[Bruce Hopf]

I'm sorry, but I have to disagree with you. This is not a dreaded chain saw oil thread at all. There is a lot of members here, such as myself, haven't had the chance to know anything, or too much about synthetic oils, for chain saws.
My last high way tractor (semi) that I owned had synthetic gear oils in the transmission, and rear ends. Still new to me, and I sold my last truck 10 years ago, and haven't given synthetic oils any more though till now.
Till a year ago, I didn't know too much as synthetic two stroke oil (don't know too much about it yet, but learning as I go here). I heard about it before, but that was a while ago. About 7 years ago, and again, never given it too much thought.
So far, I've learned a bit, but there is a lot more to learn about this subject, and I Appreciate all the information, and the time that you have given, to start this thread, and the others that have posted their input here as well. Thanks again for all the help, and advice. Bruce.

[hddnis]

Originally Posted by windthrown

Seems like you are spending a lot more money than you need to on premix though. I bet you could cut a deal with a motorcycle shop and get Motil or Elf for a lot less. I pay $12 a liter for Elf 2T... that is $45.42 a gallon. 37% cheaper. Seems like 'a fix' would be worth it, for the bottom line.

I know you're right and in time I'll switch.

Was a time when I tried every new idea that came along. I learned alot from doing it, some the hard way. Now I just like things to run and keep running.

The possible savings are very attractive and that is why I'll give it a shot in time. It will be after the first of the year; too much going on right now. My guys can go by the dealer and pick up more when they need it and that keeps it simple right now.



Mr. HE

[windthrown]

Originally Posted by Bruce Hopf

I'm sorry, but I have to disagree with you. This is not a dreaded chain saw oil thread at all.

Give it time. I have opened Pandora's Box, as it were. On some other sites this led to huge debates and arguments over viscosity, the meaning of 'lean' and all kinds of petroleum details. But in the meantime, I hope some here are enlightened. I went through a learning curve on premix oils myself, and once settled for the Castrol 2T blue goo. Before that I used generic oils, or even TCW oil, and regular gas in my saws. No longer. I saw the gospel of synthetics after using Mobil 1 'Racing' 2T. I was and remain a convert of synthetic premix (though I still use dyno in my truck and 4 strokes, it comes down to changing the filtering in engines with a sump).

The ex is still convinced that good oil and gas is a myth. The civil workers in Douglas County, OR all run 290s, and they use, "reg'lar gas and cheap ohl in them, juss fine." Stihl saws are designed for running mid grade gas in the states. Also cheap generic dyno oil may cause problems, as listed by several of us above. But she still insists on using what the county guys do, so far be it from me to tell her otherwise. The 290 and the 210 are her's to destroy as she pleases.

Originally Posted by Bruce Hopf

So far, I've learned a bit, but there is a lot more to learn about this subject, and I Appreciate all the information, and the time that you have given, to start this thread, and the others that have posted their input here as well. Thanks again for all the help, and advice. Bruce.

Well, I'll be damned, that is just way too civilized. I am used to a debate by now, with lobs and back-stabbing, negative feedback and a lot of screaming and yelling about oils and brands, and who burned what saw up using what, and all the rest. And them county boys down in Douglas County, well, the 290s are not their saws anyway. No amount of arguing with them was gonna do anything. Government employees for you.

I will see what else I have that I can dig up and post here. I have heaps of the stuff posted on some other forums. I know I have more detailed stuff on the testing of oils as well. Also more on pre-ignition in Stihl saws when using regular gas. The JACO ratings that used to be online seem to have been removed, and they now charge for that information on the site I go it from. Good thing I got a hard copy. Maybe I have a PDF file of it someplace too.

[windthrown]

Ok, since you are being such good students, here is a PDF file I dug up from someplace. I forget where I got it from, but it is a comprehensive failure analysis of 2-stroke piston failures due to bad gas, not enough oil, bad saw tuning, air leaks, and other typical casues. Its from a Jonsered service manual. Not that J-red and Huskys tend to have one pistin ring, whereas two are more typical in Stihls.

[windthrown]

This was written by Rick Sieman for Offroad.com. He is discussing 2-stroke dirt bike engines here, but most of this stuff applies to chainsaws as well. Heck, without 2-stroke motorcycles, we would not have much in the way of good chainsaw premix oils, if anything. I had a Suzuki Trail 90 when I was 15-1/2 and got my first drivers license. I rode that thing into the ground, but it was a geat bike. It had an oil injector and tank, so I did not have to mix my premix like my brother did on his Yamaha Enduros.

Quote:
RICHER? LEANER? WHAT WORKS AND WHY

Let’s see … your bike is running on the rich side, so you put less oil in the gas to lean it out. Wrong.

Or maybe your bike is running a bit too lean, so you figure that if you put more oil in the gas, that should take care of the problem. Wrong again.

You would be surprised at the large number of riders who don’t have a clue what to run in their two stroke. I know; dozens of people write my DON’T ASK column asking that question.

Many dirt bikers are mixing their gas at ratios as high as 75 to l, or even 100 to 1 with the new generation oils, in the belief that their bike will put out the most horsepower at a higher ratio. Riders who foul plugs all the time, are putting less oil in their gas/oil mix, in the belief that the oil is fouling the plugs, and many racers are trying to solve “too rich, too lean” problems by changing the gas/oil mix instead of the jetting.

There are a few good reasons to run a fuel/oil mix at ultra thin ratios in a two stroke. High ratios such as 100 to 1 are usually environmental reasons, such as for outboard boat motors. The exhaust of an outboard motor goes directly into the water, and environmentalists are worried about the oil in the mix polluting the lakes and rivers.

There’s a myth that the less oil you use in your gas, the more horsepower you get. Conversely, many dirt riders actually forget to put any oil whatsoever. We know of one guy who forgot to mix oil into his gas and actually rode it for two hours without seizing it. All the bearings were ruined and the piston was worn out, but it didn’t seize!

Actually, you can get more horsepower out of a two-stroke engine with enough extra oil in the gas, because the oil provides a better ring seal and, therefore, more compression. People think that gas burns more efficiently with less oil, and therefore you get more performance. It almost makes sense if you look at that one statement alone.

The seal of the piston is critical. If you remove the lubricants from the gas, the viscosity of the mixture becomes lighter and more prone to vaporization. With a lean mixture, there is less oil to seal the rings. The sealing of the rings has more to do with the performance of the engine than the possibility of having better-burning gas with an ultra-lean gas/oil ratio.

The old fashioned two-stroke oil that was on the market years ago, was designed to be run at 20:1 and was basically petroleum with a few (very few) additives. Then, when high-performance oils came along, they cost more to make and sold for a higher price. They got into these high mixing ratios in order to justify the higher prices.

If you do foul plugs, it is more than likely caused by poor jetting, not a bit too much oil. If you get your bike jetted correctly, have a fresh plug and a strong ignition system, you won’t foul plugs.

When the motor is idling, or at lower rpms, that’s when the machine has a greater chance of fouling a plug. Minibikes and 125s have even less chance of fouling plugs, because they are ridden at such high rpm. Because of the ultra high rpm, the load on a given part is much higher on a 125, than on an Open bike.

Plugs should not foul at richer ratios if you are using high-quality oil in the mix. High-quality oils will have a good detergent/dispersing package that holds down the contaminants which produce plug fouling.

A typical example: you go from a 50:1 ratio to a 20:1 ratio. Your engine will now run leaner, and you’ll have to make jetting changes. You’ll need bigger (in number) jets because the oil molecules are thicker and the flow rate (the amount coming through the jet) is less.

Aha! The volume of fuel has changed. The oil takes up some volume that the gas used to occupy, so your engine is getting less gas and needs to be richened up.

So which ratios should two-stroke gas/oil should be mixed? A properly jetted engine will run better, last longer and develop more power at a lower oil ratio than at a higher one. But what is the proper amount, and how do you know a quality oil from a bad one?

The ratio a rider should use in his two-stroke will depend on the size of the machine and the type of riding being done. An 80cc racer will require much more oil in the mix than a 500cc play bike. The best bet is to consult the owner’s manual and follow the advice of the engineers who designed the motorcycle.

As for which oil to buy, that depends on the type of riding being done. Someone who races will require a higher-quality oil for its superior ingredients and properties, than someone who only play rides and doesn’t put a lot of strain on his engine. A good, high-quality oil will cost more money than a poor-quality oil, because of the higher cost of ingredients, such as synthetic diesters and ash less detergent dispersing packages. Quality ingredients cost more money, and that makes the quality oils more expensive.

Our advice then, is to buy a quality oil and run it at a moderate ratio. We’ve used 32:1 for many years. In race bikes that are ridden hard, we might go a trifle richer at say … 28:1. For a trail bike, 40:1 would be the way to go, assuming that you used a quality oil. If you own a mild-mannered bike, consider a 50:1 ratio.

One of the things you should do, is run high octane gas with any two-stroke mix. When all of the two strokes (the old days) were developed, they all used Castrol petroleum oil at a 20:1 ratio and found that 92 octane gas had the octane reduced to 72 with presence of that much oil. Modern oils won’t affect the fuel quite as much, but if you started with 86 or 87 octane regular fuel, you can see where you’ll end with a very low octane mix. You could end up with a “pinging” bike.

Race gas? You don’t need it in your two stroke unless you’re a pro or expert, and most expert level riders are on the new generation four strokes.

THINGS YOU SHOULD KNOW

Use only two stroke engine oil in two stroke engines. Do not use car engine oil like SAE 10W-30W, or the like. Two stroke engines burn oil and are designed to do this, and require the proper oil in the gasoline.
Mix the gasoline and oil thoroughly. One method is to take your gas and oil can to the gas station and mix right there at the pump. Fill the gas can about 1/3 full and then add the proper amount of oil, then fill the container. The gasoline pumping quite rapidly out of the nozzle mixes the oil and gas together quite well.
Shake the gas can vigorously before filling your gas tank. The oil must be suspended evenly in the mix, so the engine gets lubricated evenly. If the oil is not mixed thoroughly, the engine starves for lubrication, and the spark plug gets oil stuck on it.
Gasoline is also important. Head for your manual for types of gasoline and octane rating your engine requires. Some older engines require leaded gasoline. Most of the newer engines run on leaded or unleaded.
Once gasoline is mixed, use it. Don’t buy 10 gallons of gasoline and use five gallons. Gasoline allowed to sit gets stale and gummy. This gummy stuff sticks to carburetor parts and air passages, which eventually will restrict air flow, thus changing the air-gasoline mixture.
All the major manufacturers produce two stroke racing engines in their off-road motorcycles. Virtually all of them recommended 20:1 or 24:1 mix ratios. What the actual factory mechanics did at racing events was very telling. Their teams (admittedly not running "stock" engines) but were running engines putting out even more power for the displacement class, followed the same rules.
1) The higher the RPM's the engine turned, the more oil they ran in the fuel. (e.g. a 125cc machine that routinely lived in the 10,000 - 13,500 rpm range ran 20:1 or 24:1 -- The 250cc engines that ran between 6,500 and 9,000 rpm ran 32:1 or 40:1, and the Open Class machines (251cc and up by AMA, but they were all 400+cc engines, usually 465's, 490's, or 500cc) ran 50:1.
(2) Additionally. Husqvarna did some testing in the mid 70's that was very interesting. They put 3 identical stock engines on a dyno and ran them for several days at varying RPM and load conditions. Then both motors were torn down and inspected. The engine running CASTOR based oil had the least wear, followed by the synthetic oil, and finally the engine running standard 2-cycle oil.
(3) A second test they performed was to run synthetic in 2 identical engines and one was run at 24:1, the other was run at 50:1 The engine that ran 24:1 had less piston skirt wear, and less rod bearing wear, but had the same main roller bearing wear as the engine run at 50:1.

[rick]

Here's a couple of PDF's of the JASO Implementation Manual and an approval/license list from about twelve months ago.

It'll give you an idea of what goes into testing an oil for certification.

[SawTroll]

Originally Posted by windthrown

The dreaded chainsaws oil thread

You'd better call in Gary!

[windthrown]

Originally Posted by rick

Here's a couple of PDF's of the JASO Implementation Manual and an approval/license list from about twelve months ago.

It'll give you an idea of what goes into testing an oil for certification.

Yah, those are the lists I have hard copies of and could not find on the web anyplace. For free, that is...

I use Elf MOTO XT 2. The bottle says its JASO FC rated, and ISO-L-EGD rated, so my first post is probably not accurate in that JASO FD and ISO-L-EGD have the same tests and ratings. Or they test to ISO D level and JASO to C level, and in reality they would pass the JASO FD ratings if they paid for the added testing. I am not sure why there is a difference.

[windthrown]

OK, this is an oil thread, but it is really a premix thread. You cannot talk about 2-stroke oil additives without some discussion about gasoline. Basically oil has an impact on the gas, and gas has an impact on the oil. The main impact on gasoline that oil has is that it greatly reduces the octane rating. Octane is a number applied to gasoline that describes how evenly gasoline burns. This is important in relation to the compression ratio of gas engines. The more compression an engine has, the higher the octane that is required to avoid pre-ignition. Pre-ignition happens when your gas engine diesels, or knocks. To explain this, some background here is required on the internal combustion engine, and fuels that are used in them. Diesel engines do not have ignition systems; they fire merely by compressing diesel fuel until it explodes. Diesel engines have much higher compression ratios than gasoline engines, typically between 15:1 and 21:1. Diesel fuel has more energy than gasoline does as well. This is becasue diesel fuel is made up of heavier hydrocarbon elements than gasoline. Typically, diesel is made up of molecules with 8-21 carbon atoms. Breaking these longer chain hydrocarbons generates more energy per unit volume. Diesel engines to not require high octane. They run by pre-ignition, so diesel typically has an octane rating of only about 25.

In comparison, gasoline is made up mosly of molecules with 4 to 12 carbon atoms. Burning these smaller molecules releases less energy per unit volume than diesel. When gasoline engines were first developed, octane was really low, about 40 was typical until about 1930. What happened was that when gas engine builders made the compression ratios higher, the gas would pre-ignite before the spark plug fired. This led to engine damage. Gas engine builders wanted higher compression ratios, especially for aircraft engines, becasue they could get more power out of higher compression engines at various altutudes. So Avgas was developed then with an octane up to about 80. In the 1920s they had found that the addition of lead to gas improved octane. Lead was added to the national gasoline supply so that higher compression engines could be developed and sold. Lead was used here until the 1970s, when it was discovered that lead was making its way from gas into the atmosphere, and in places like Los Angeles, CHP officers were driving around with half the leathal lead level in their bloodstreams. Durng WWII gasoline development really took off (literally, and figuratively). Better gasoline engine technology for fighter and bomber aircraft was in high demand. By the end of the war both Germany and the US had gotten octane ratings as hight as 150.

Since the 1970s, other additives have replaced lead in gasoline. Lead was phased out here, first with low-lead gas, and now with unleaded gas. Avgas still has lead in it here to maintain the high level of octane required for flying at various altitudes. Safety trumps the environment, it seems. California experimented with MTBE which was a natural byproduct of gasoline production and is a gasoline oxygenate, meaning it lowers the pollution caused by burning gasoline. MTBE was actually required in Califonia intended to lower smog and air pollution. However, it was also found that MTBE contaminated ground water and lakes, and it travels great distances in the ground. It has since been banned in the US. Other additives have been developed, like MMT which is widely used in Canada and Australia. It boosts octane. It was first considered a hazardous material in the states and banned here, but the courts overturned the ruling and it is again allowed in the US as an additive in gasoline. Of late, ethanol is being added to gas in larger amounts in the US and Europe. It is also an oxegenate, and it is typically blended at the rate from between 5% and 10% by unit volume. Ethanol also has higher octane than unleaded gasoline, with an octane rating of about 116 as compared to regaular gas here which is 87. Ethanol also has about 60% of the energy of gasoline by volume.

Which brings us to another aspect of gas; it is not the same throughout the world. Nor is it blended the same. For example, the US and Canada have lower octane (listed here is the AKI, or anti-knock octane number). The gasoline available here mostly has 10% ethanol in it now. Europe has higher octane gas with about 5% ethanol now. In the US/Canada, regular gas is rated at 87 AKI octane, and in Europe super gas is AKI 90 octane. In the US/Canada, premium gas is 93 AKI octane, and in the UK and Germany SuperPLUS gas is 94 AKI octane. You can also buy 100 octane gas in Germany at most gas stations there. Gas in the US is mainly regulated by the states, so that additives and blends of gasoline are different between states. Until this year I could buy 100% gasoline in California and Oregon, but no longer. By law it now has to be blended with ethanol, to reduce emissions, and to save the planet by burning fermented corn. Another difference in gasoline sold in the US is seasonal variation. We have summer and winter blended gas here. The difference is that summer gas evaporates at a slower rate than winter gas does. Remember that gasoline is a blend of hydrocarbons? To account for that, summer grade gasoline typically has less butane in it and winter grade gas has more butane in it. Butane is a cheap component of gas, being the lightest of the gasoline hydrocarbons (C-4). Hence winter grade gasoline is cheaper to make and generally is priced less at the pump (if oil were to remain stable when the prices were compared, which of course it never does).

So, there you have some information on gasoline. My next post will be about the impact of gas additives on 2-stroke premix oils, particularly ethanol.

[Bruce Hopf]

I don't wish to cause an argument, but the diesel engine wasn't the first engine to be built. In fact the Gasoline engine was built by Samual Brown, over 70 yeas prior to Diesel engine built by Rudolf Diesel.
In 1823, Samual Brown constructed a gas engine, that ran a boat successfully on the Thames, and a carriage of the streets of London England.
In 1892, Rudolf Diesel patented the diesel engine, and had his first successful engine in 1897.
History of the Gas Engine
Rudolf Diesel - Inventor of the Diesel Engine Rudolf Diesel
Just thought that I'd clear that up. Bruce.

[rick]

Originally Posted by windthrown

<snip>
For example, the US and Canada have lower octane gasoline available mostly with 10% ethanol in it now. Europe has higher octane gas with about 5% ethanol now. In the US/Canada, regular gas is rated at 87 octane, and in Europe super gas is 90 octane. In the US/Canada, premium gas is 93 octane, and in the UK and Germany SuperPLUS gas is 94 octane. You can also buy 100 octane gas in Germany at most gas stations there. Gas in the US is mainly regulated by the states,
<snip>

whoops, octane is measured differently around the world

In NA you use the AKI (Anti Knock Index) which is an average of RON (Research Octane Number ) and MON (Motor Octane Number)

In Europe, here and most all the rest of the world we use RON/ROZ.

98 RON is roughly = to 93/94 AKI.

Octane rating - Wikipedia, the free encyclopedia

I have a US FCC paper on fuel too, I'll try and upload it.

[windthrown]

Originally Posted by rick

whoops, octane is measured differently around the world

Yes, octane is measured differently (I thought I mentioned that), but I used the comparable AKI standard used here in the states. Even though it is not labeled that way in Europe and other places, that is the typical (and comparable) value of the octane rating of gas sold worldwide. Octane is not a stable value; it falls once gas leaves the refinery. Gasoline is refined and delivered differently around the world. Hence it is impossible to really accurately compare gas. So I used an average of the refinery and measured at the pump, or AKI value. The AKI values listed are the ones measured/averaged/posted on the internet for gas found in those locations.

Pandora's Box opens... see why it is named, 'dreaded'?

[windthrown]

Originally Posted by Bruce Hopf

I don't wish to cause an argument, but the diesel engine wasn't the first engine to be built. In fact the Gasoline engine was built by Samual Brown, over 70 yeas prior to Diesel engine built by Rudolf Diesel.
In 1823, Samual Brown constructed a gas engine, that ran a boat successfully on the Thames, and a carriage of the streets of London England.
In 1892, Rudolf Diesel patented the diesel engine, and had his first successful engine in 1897.
History of the Gas Engine
Rudolf Diesel - Inventor of the Diesel Engine Rudolf Diesel
Just thought that I'd clear that up. Bruce.

So noted, and corrected/removed. Old age... memory is going. Too many beers...

[rick]

Yep, your right, I only glanced through it and saw the higher octane bit.
Might pay for me to read it properly next time......

Couldn't upload the FCC fuel paper.
I use Open Office and the attachment uploader didn't recognise the file.

[Steve Tipton]

I thought diesel fuel was rated as Cetane rating and petrol (Gasoline) as octane rating?

[rick]

Originally Posted by Quintrex

I thought diesel fuel was rated as Cetane rating and petrol (Gasoline) as octane rating?

Cetane and octane are ratings of two totally different things.

Cetane is a measure of a fuels delay to ignite, (the higher the cetane # the less delay between injection and ignition in a compression ignition/diesel engine )

Octane measures a fuels resistance to detonation (self ignition) in a petrol/spark ignition engine.

Australian diesel is pretty good these days, it pretty well mirrors the average European diesel fuels.
Cetane varies between about 48 and 51 from the majors. Last I checked Caltex was the lowest and BP the highest with Shell in the middle, but it depends on which refinery it comes from.
Sulphur should be <10ppm across the board these days which is quite a bit better than the US and equal to Europe AFAIK.

[windthrown]

Well, I will use this as a my next segway...

I posted the typical octane on diesel only to compare it to gasoline, not to say that it was typically sold rated for octane. No point in that, as diesel self-detonates by design, so you actually want low octane in diesel. Gas is the opposite. You want higher octane gas to avoid pre-detonation from compression and to fire only when the spark plug fires. Pre-detonation in gas engines is called knock (due to the loud klanging, which is the sound of a proper running diesel). As said above, cetane is the opposite of octane, and diesel is indeed sold rated for cetane. No need to get into that here though, as I am not aware of any chainsaws sold with diesel engines. My point in brining up the diesel engine at all is to explain why you want higher octane gasoline. The higher the octane rating, the slower and more evenly the fuel burns. This is an issue in 2-storke engines, becasue adding premix oils drops the octane (I have read several places that a 50:1 gas to oil ratio will drop gas octane by about 2 points). The knock does not seem to be as much an issue in chainsaws as much as the uneven burning of running lower octane gas. Uneven burning fouls pistons and causes chainsaw engine damage. You could call it partial pre-detonation, or just uneven flaring of the gas when it is ignited by the spark plug. This causes uneven pressure in the combustion chamber and can warp the surface of pistons, and cause piston skirt to slap the side of the cylinder wall. You want more even pressure on the piston when the gas is ignited. To get that, you want higher octane gas.

I am not sure about all chainsaw manufacturers, but Stihl recommends gas that is AKI 89 octane or better. 89 octane gas here in the states is called 'mid-grade'. In Europe, that is typically one octane point less than the lowest grade gas available there. So in Europe this is not really an issue. However, here in the states and Canada, putting low octane regular gas in saws is fairly common (I have done it myself). Regular gas here is AKI 87 octane. If gas stayed at 87 octane that might not actually be so bad. 87 is an average of RON (research octane) and MON (motor octane). However, gasoline is unstable and octane falls from the point that it is refined. It drops during shipping to the gas station, and drops in the gas station tanks, and drops again when it is pumped into a gas can and sits in your garage, and drops more when oil is added, and drops more when it sits in the chainsaw gas tank, and it drops one last time when it is mixed with air by the carb and heated in the saw's lower engine before being pumped into the combustion chamber and ignited. Many chainsaw dealers blame 'bad gas' for a lot of engine scoring and damage that they see in chainsaws. 'Bad gas' is typically gas that has sat in a can in a warm place for over a year in a garage or wherever. By that time the octane has gone through the floor, and the tendancy for pre-detinatin and uneven gas burning using old gas in a chainsaw can cause all kinds of problems. Similar to gas that has not been properly mixed with oil, or gas that is not mixed with any oil at all (called 'straight gas').

I will leave it here and talk about gasoline stabilizers next.

[windthrown]

OK, more here on gasoline, and more specifically, on how gas deteriorates and why you may need to use a gasoline stabilizer.

From the pump at the station, gasoline will usually remain "fresh" for about two to three months. If you are using your gas at a faster rate than three months, you porbably do not need to worry about gas deteriorating. However, if you are not using all the gas within three months time, or let it set in your chainsaws longer than that, you should add a fuel stabilizers to it. With stabilizer, gas can last up to a year (or add fuel stabilizer at double strength, and it can last up to two years). Gasoline is unstable and if you leave it untreated in a gas can or in your chainsaw 'over winter' for 4 or 5 months, you can get gum deposits in your carb, the gas can separate on you, absorb moisture, oxidize, attack your seals and plastic, and even turn rancid.

Straight gasoline deteriorates in three main ways. Those ways being, oxidation, evaporation, and contamination. Badly oxidized gasoline has a rancid odor and/or a dark color to it. If you notice a foul odor or notice that the gas is turning dark, toss it out. OK, not such a good idea these days. So what I do to dispose of bad or quesitionable gasoline is to pour it onto the firewood pile and let the wood soak it up. Then I burn the wood in an outside fire ring. That is not legal in this state, and technically I should take it to the hazardous waste site for safe disposal. I also have used it to burn out wasp nests here. That is also not legal, but it is the only thing that works. I have tried a lot of other methods to get rid of ground nested yellow jackets here, and burning them out of their in-ground condos with gas is the best method.

Evaporation of some of the more volatile components of gasoline is pretty much impossible to detect. If the first 10 percent of a gasoline distillates above 160*F (summer blend in the US) or 140*F (winter blend in the US), then gas no longer meets the ASTM automotive spark-ignition engine fuel specifications. What this means is that the lighter hydrocarbons like butane and propane in gasoline tend to evaporate first. These molecules have very high octane, and as a result of evaporation, the gas becomes lower octane over time. There are also the really volatile aeromatic hydrocarbons in gas like toluene and benzene which also evaporate fairly fast. So over time, just sitting around, your gas morphs into something else that becomes more and more like diesel fuel. Gasoline will also form solids over time, as the heavy hydrocarbons condense and settle out. This causes gumming or gunking up in carberators, and fuel tanks, as well as fuel lines. This is not desirable in chainsaws, as it will require that you take out your carbs and soak them in white gas (Coleman fuel) and clean out your gas tank and gas lines.

Contamination of gas happens when dirt, water and rust get into it, and when parts of the gas itself solidifies. Sometime you can see if gas has dirt and rust in it. You usually cannot tell just by looking if it has water in it. Rust and dirt can be filtered out by your chainsaw gas line filter, but the water cannot. Lately the issue of water in gas has become a big issue in the US and Europe with the addition of ethanol. Ethanol is an alchohol. As such, alchohol has the ability to dissolve in water (like in your afternoon cocktail or beer) and in gasoline. Also alchohol likes to suck up water. Once it combines with water it wants to separate from the gas with the water. This is called separation, and is not a good thing in your gas tank, especially in a chainsaw. Ethanol also has other issues, particularly that it can etch aluminum, corrode seals and gaskets, and break down rubber and plastic compounds. Also ethanol will dissolve water based particles in all the gas tanks along the way (at the gas station, in your gallon jug, and in your chainsaw) that would otherwise be left behind by staright gas. Those contaminants can wind up being sucked into the carberator and engine of your chainsaw.

So... what is the solution to all of this? If at all possible, buy 100% gasoline. Buy mid-grade or better gas in the US and Canada. Using ethanol blended E-10 gas will not usually casue problems in your chainsaw as long as it is used at a fast enough rate. You can use AvGas, which is 100% gasoline and is 100+ octane, but in the states it still has high levels of lead in it (2-5 grams per gallon) to attain the high octane rating. Use all your gasoline within 2-3 months of buying it. If you do not use gas at a fast enough rate, add a gas stabilizer to it when it is fresh. It cannot 'freshen up' old gas. If you are going to store gas for a really long period of time, add a gas stabilizer at two times the rate, and it will last for about two years. If you have to buy ethanol blended gas, there are new ethanol gas stabilizers that will bind with any water and keep the gas fresh for up to a year or two. I use STA-BIL myself. Some 2-stroke oils already have gas stabilizer in them. From what I have read, adding 2-stroke oil will generally not degrade gasoline. There is an added complication of adding some types of 2-stroke oils to ethanol blended gas. I will get to that in another post.

[rick]

And if I can add one thing to Windy's excellent post, the almost ubiquitous plastic (HDPE) fuel containers and fuel tanks are actually permeable to fuels, particularly petrol, which means that the aromatic components that Windy talked about above and are mostly responsible for the octane rating of your fuel volatise off quite quickly.
The higher the fuels octane rating, the worse the problem as more aromatic components are present.

The smaller the tank, the worse the problem too as the surface area of the tank to volume contained is much greater for a given quantity of fuel. This is the reason it's recommended by saw manufacturers to dump mix older than six to eight weeks old.

Steel containers don't have this problem, and fuel can be safely stored for many months if not vented to the atmosphere.

[windthrown]

I bounce back and forth between using steel and plastic gas cans. Plastic breathes, and steel rusts. Some choice. I use mainly plastic tanks and fuel stabilizer to keep the ethanol blended gas from vaporizing and causing problems after sucking up water. It rains a lot here in fall/winter/spring. I also only buy 2 gallons of premium (91 AKI octane here) gas at a time, and mix it into a gallon container with oil. Keep it smaller and fresher, and even then I use STA-BIL. I also drain gas from saws I am not going to use for more than a month. I have stored some 2-stroke engines for over 10 years without using them, and filled them with gas and they fired right up.