Gas Oil MIxture Ratios
- Thread starter erniezen
- Start date
Model make and year produced would be helpful.
Sounds like an old saw.
Is it a Stihl and does it say if not using Stihl OIl mix 25:1 ?
Sounds like an old saw.
Is it a Stihl and does it say if not using Stihl OIl mix 25:1 ?
What, is this thing 40 years old?
with nowadays synthetic FC/FD 2stroke oils I would not bother...1:50 and u are still on safe side...
Using that ratio on old Tomos 770 (copy of husquarna L77) and other one with 1:40 on fuel cap...without problems!
Using that ratio on old Tomos 770 (copy of husquarna L77) and other one with 1:40 on fuel cap...without problems!
If it says 25:1 I would give it 25:1.
Two-Stroke motors built in the last 10~20 years are generally 50:1 or even 100:1. But aside from lower weight, improvements in small motor technology over a similar time span means you can often replace a 2-stroke motor with a 4-stroke model.
Aside from not having to buy relatively expensive 2-stroke oil, there is typically a large difference in fuel consumption ... 4 stroke small motors get *much* better fuel economy, and combined with not having to buy the 2-stroke oil, means significant savings in operating costs.
I would not advocate replacing the 25:1 unit "just because", but if the operation and economics point toward replacement, see if a 4-stroke replacement is available, and if not, consider waiting until one is.
Two-Stroke motors built in the last 10~20 years are generally 50:1 or even 100:1. But aside from lower weight, improvements in small motor technology over a similar time span means you can often replace a 2-stroke motor with a 4-stroke model.
Aside from not having to buy relatively expensive 2-stroke oil, there is typically a large difference in fuel consumption ... 4 stroke small motors get *much* better fuel economy, and combined with not having to buy the 2-stroke oil, means significant savings in operating costs.
I would not advocate replacing the 25:1 unit "just because", but if the operation and economics point toward replacement, see if a 4-stroke replacement is available, and if not, consider waiting until one is.
My snowblower says 40:1 (Craftsman) and my Husquvarna chainsaw specs 50:1. I have been using Amsoil sabre for a couple years now mixed probably around 75:1, though I'm a little sloppy. Basically I just shoot for a ratio between
Seems to work well with less smoke, and particularly with the snowblower it seems to have a little more power.
Seems to work well with less smoke, and particularly with the snowblower it seems to have a little more power.
Direct answer to a direct question: Maybe in the short term.
Oil displaces fuel (doesn't burn as fuel). Run what your carb is jetted for or jet your carb for what you're running. If you run ultra-premium-super-mega-concentrated unicorn tears that says it's good for 1000:1 mix then be aware you need to re-jet the carb to account for more fuel and less oil. Also keep in mind 10% ethanol in average fuel is another dilutant requiring yet another carb jet change for a given pump-nozzle to oil mix ratio. Best bet is to have a competent 2-stroke mechanic tune your engine to run best (but not totally on the ragged edge) of the fuel/oil mix you want to use in the average temperatures you intend to operate in (that includes octane, ethanol content, and oil mix ratio). If all but one of your OPE engines call for 40:1 mix then have your 25:1 chainsaw tuned to run 40:1.
Oil displaces fuel (doesn't burn as fuel). Run what your carb is jetted for or jet your carb for what you're running. If you run ultra-premium-super-mega-concentrated unicorn tears that says it's good for 1000:1 mix then be aware you need to re-jet the carb to account for more fuel and less oil. Also keep in mind 10% ethanol in average fuel is another dilutant requiring yet another carb jet change for a given pump-nozzle to oil mix ratio. Best bet is to have a competent 2-stroke mechanic tune your engine to run best (but not totally on the ragged edge) of the fuel/oil mix you want to use in the average temperatures you intend to operate in (that includes octane, ethanol content, and oil mix ratio). If all but one of your OPE engines call for 40:1 mix then have your 25:1 chainsaw tuned to run 40:1.
Oil mix ratio is more a function of oil technology than engine technology. In other words, the oils generally available at the time were of a quality that they needed to be a more oil heavy mix, ie 25:1. As oil technology advanced, then we went to 32, 40 and now 50:1. There is some difference is metal coating technology, but I don't worry about it. I use a good oil, at 50:1 in everything. I like Echo Power Blend syn, and haven't had any troubles with anything I've used it in. Maybe a slight carb adjust and away you go!
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Originally Posted By: Kamele0N
with nowadays synthetic FC/FD 2stroke oils I would not bother...1:50 and u are still on safe side...
Using that ratio on old Tomos 770 (copy of husquarna L77) and other one with 1:40 on fuel cap...without problems!
Yep. I went to 50:1 on my 32:1 and 40:1 equipment some years ago and everything runs well. Lots of discussion here and on OPE forums confirming this.
with nowadays synthetic FC/FD 2stroke oils I would not bother...1:50 and u are still on safe side...
Using that ratio on old Tomos 770 (copy of husquarna L77) and other one with 1:40 on fuel cap...without problems!
Yep. I went to 50:1 on my 32:1 and 40:1 equipment some years ago and everything runs well. Lots of discussion here and on OPE forums confirming this.
It is a 2015 Model year. Ad says its a Petro 52cc Chinese Chainsaw distributed out of California.
Specs on ad says gas/oil mixture is 25:1. Thought it was odd with all the threads indicating to use 40:1 or 50:1 ratios.
Ad can be found on Ebay under Petro 52cc Chinese Chainsaw.
Thanks for your help.
Specs on ad says gas/oil mixture is 25:1. Thought it was odd with all the threads indicating to use 40:1 or 50:1 ratios.
Ad can be found on Ebay under Petro 52cc Chinese Chainsaw.
Thanks for your help.
I read the review at: http://www.ebay.com/gds/52cc-Chainsaw-Chinese-made-various-brand-names-/10000000021544913/g.html
Break in at 20:1, then run 25:1!? The Chinese are really behind the times!
Break in at 20:1, then run 25:1!? The Chinese are really behind the times!
Many of the Chinese don't have access to proper two stroke oils. This saw is designed for 3rd world usage, using lubricants available to 3rd world users (*such as mixing plain motor oil into the gas, like we used to do 75 years ago) . If you use a modern FC or FD two stroke oil, you can safely run it 50:1. You might need to adjust the carb a bit to get it to run right.
If the carb lacks a lot of adjustment, a 40:1 ratio will probably be in the ball park.
I highly doubt that you will be using this saw for hours on end. Therefor, go buy a can of TruFuel 40:1 premix gas and call it a day. It lacks ethanol and has fuel stabilizer so it will last a long time and not give you any grief.
If the carb lacks a lot of adjustment, a 40:1 ratio will probably be in the ball park.
I highly doubt that you will be using this saw for hours on end. Therefor, go buy a can of TruFuel 40:1 premix gas and call it a day. It lacks ethanol and has fuel stabilizer so it will last a long time and not give you any grief.
Originally Posted By: erniezen
It is a 2015 Model year. Ad says its a Petro 52cc Chinese Chainsaw distributed out of California.
Specs on ad says gas/oil mixture is 25:1. Thought it was odd with all the threads indicating to use 40:1 or 50:1 ratios.
Ad can be found on Ebay under Petro 52cc Chinese Chainsaw.
Thanks for your help.
There's a few youtube clips on these Chinese chainsaws. You don't have to run them so oil rich. They're hit/miss in terms of quality, as you'd expect from the price. ~20", 52cc saws shipped to your door for $100. Some even come with extra recoil start assemblies and spare parts. LOL
It is a 2015 Model year. Ad says its a Petro 52cc Chinese Chainsaw distributed out of California.
Specs on ad says gas/oil mixture is 25:1. Thought it was odd with all the threads indicating to use 40:1 or 50:1 ratios.
Ad can be found on Ebay under Petro 52cc Chinese Chainsaw.
Thanks for your help.
There's a few youtube clips on these Chinese chainsaws. You don't have to run them so oil rich. They're hit/miss in terms of quality, as you'd expect from the price. ~20", 52cc saws shipped to your door for $100. Some even come with extra recoil start assemblies and spare parts. LOL
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Originally Posted By: JTK
There's a few youtube clips on these Chinese chainsaws. You don't have to run them so oil rich. They're hit/miss in terms of quality, as you'd expect from the price. ~20", 52cc saws shipped to your door for $100. Some even come with extra recoil start assemblies and spare parts. LOL
I've bought real deal good running Stihl, Husky, and Echo chainsaws for well south of $100. Just got to know where to look.
There's a few youtube clips on these Chinese chainsaws. You don't have to run them so oil rich. They're hit/miss in terms of quality, as you'd expect from the price. ~20", 52cc saws shipped to your door for $100. Some even come with extra recoil start assemblies and spare parts. LOL
I've bought real deal good running Stihl, Husky, and Echo chainsaws for well south of $100. Just got to know where to look.
Originally Posted By: bubbatime
I've bought real deal good running Stihl, Husky, and Echo chainsaws for well south of $100. Just got to know where to look.
A workable Stihl for under $100 would be a highly unusual find in my area.
I've bought real deal good running Stihl, Husky, and Echo chainsaws for well south of $100. Just got to know where to look.
A workable Stihl for under $100 would be a highly unusual find in my area.
Originally Posted By: erniezen
52CC Chainsaw engine specs require 25:1 gas oil mixture. Have seen other threads were users recommend 50:1 or 100:1. Can you change ratios like that without diasterous results?
80:1 Amsoil 2 stroke oil and call it a day. I have had best performance with that combo.
Nothing is going to result if you go to 50:1. Oil nowadays has changed a lot since back then when that mixture and 16:1 oil ratios were common. That is why leaner mix ratios are used.
52CC Chainsaw engine specs require 25:1 gas oil mixture. Have seen other threads were users recommend 50:1 or 100:1. Can you change ratios like that without diasterous results?
80:1 Amsoil 2 stroke oil and call it a day. I have had best performance with that combo.
Nothing is going to result if you go to 50:1. Oil nowadays has changed a lot since back then when that mixture and 16:1 oil ratios were common. That is why leaner mix ratios are used.
I hear all across the ol' innerweb how oil today is so much better than the oil of yesterday. So, for full disclosures, I have been trained in lubrication technologies on the various power pkants I have worked at in the maintenance field. Also I have had a lot of vibration analysis and root cause failure analysis in rotating equipment. You can fall off in the rabbit hole of bearing design, oil wedge allowances, grease soaps, and additive packages as far as you want to. This is what I know to be true. The oil is the same. Same as it was 60 years when oil was used in the turbines of jet engines, nuclear submarine turbines and gear boxes, and various NASA rockets. What has changed, are the additive packages. Yes. They had "synthetic" oil back then too. They also had access to additives that we don't today because the EPA stuck their nose in and forced changes. Like zinc. Zinc does marvelous things to bearings. It coats the metal and under pressure acts as a replentishable sacrificial wear layer, effectively insulating the races and roller elements from ever touching. As long as the radial load and heat stayed below the manufactured engineered setpoints, it could last MUCH LONGER than MODERN technology bearings, but the EPA set guidelines on how much zinc is allowed in the additive packages. That is why "Assembly Lube" for new rebuilt engines and "Break in Oils" have really high levels of zinc. I say this because I see where people say" Yeah, but the oil today is so much better than what they had back then". Really? What was the failure rate if the old McCullough's, Partners, Pioneers, Poulans, and Stihl saws in the logging woods back in the 70's? Why is there so many legendary" Couldn't kill em' if we tried" saws from that era running 16-1 / 25-1 / 32-1 non detergent conventional 30 weight oil? If the 50-1 mix prescribed by the big 2 sawmakers are so good, why do they only offer a year warranty on pro saws? The ones that are gonna see 8-10 hrs a day 5-6 days a week running? Iys because they know its not economical to warranty them any longer than that. The OP asked about running his equipment at 25-1, go for it! Just use non detergent conventional 30 weight and tune your carb for it. If you dont know how to tune the carb then look in your yellow pages for " loggers", pick up a half a case of beer, and make your way over for a quick lesson, have him show you how to sharpen a chain with a file while the saw is laying across a tree trunk and throw those sharpening gadgets away too. Happy sawing...
