Weed eater oil mix question

[boraticus]

Originally Posted By: tmorris1
Originally Posted By: das_peikko
I'd run both at 50:1

40:1 is going to cause the engine to run dirty and load every thing up with carbon.
- NOT!


How do you come to that conclusion? 40:1 will hurt nothing and that is what I would run.


Agree 100%. The effects of running 40:1 or 32:1 will be nothing but beneficial for the engine. Back in the day, some engines ran at 16:1.

People with little to no experience with two cycle engines often spread misinformation that benefits no one. Would be wise and beneficial to provide info if one actually knows something about the topic.

 

[jeepman3071]

The difference is minimal between 40:1 and 50:1. Oils are light years ahead in technology now than they were even 10 years ago. Nothing needs to be run at 32:1 or 16:1 this isn't the 1960s anymore. I have customers who have been running 50:1 mix in commercially used equipment for years and everything else wears out long before the engines ever have.

 

[gathermewool]

My new Echo SRM-225 manual states the following:

"Echo premium Power Blend X Universal 2-Stroke Oil may be mixed at 50:1 ratio for application in all Echo engines sold in the past regardless of ratio specified in those manuals."

I'd consider going richer, but plan to stick with 50:1 for now.

 

[Cedarshark]

I own 30 chainsaws and buy/rebuild and sell them. Your question(OP) is easy to answer. Any 2 stroke motor can be burned up at ANY oil to fuel ratio if it becomes leaned out at the fuel to air ratio. The fuel to air ratio is controlled by the high and low jets in the carb. So if you cannot adjust the carb for the particular mix you are running, my suggestion is to use the mfg suggested ratio. I tune with a tach made for 2 strokes and modern saws will run between 12,000 -14,000 rpm at WOT.

 

[JLawrence08648]

I'd run both at 32:1 or 40:1

 

[ARB1977]

First time using Amsoil Saber at 80:1. My Sthil seems to run better with it. Ran their Moto mix in the can for 4 years.

 

[Silk]

I've been using 50:1 in every 2 stroke I've owned since the early '80's when synth oils became available at a good price. And a no brainer using metrics - 100mm in a 5 litre, simple as.

 

[Srt20]

Originally Posted By: Cedarshark
I own 30 chainsaws and buy/rebuild and sell them. Your question(OP) is easy to answer. Any 2 stroke motor can be burned up at ANY oil to fuel ratio if it becomes leaned out at the fuel to air ratio. The fuel to air ratio is controlled by the high and low jets in the carb. So if you cannot adjust the carb for the particular mix you are running, my suggestion is to use the mfg suggested ratio. I tune with a tach made for 2 strokes and modern saws will run between 12,000 -14,000 rpm at WOT.


Have you ever seen an engine that calls for 50:1 ratio burn down at a 32:1 ratio?? Just curious since its only 1.4oz more oil PER GALLON....

If it lean burns down at 32:1 I promise you it would also burn down at 50:1.

Also, if it has carbon build up(which is a crock too) at 32:1, it will have the same at 50:1.

 

[Warlord]

Just mix up a batch of 40:1 and don’t worry about it.

 

[boraticus]

I've got a little Shindaiwa two stroke water pump that runs at 7500 rmp non-stop for an hour or more. It calls for 25:1 and that's what it gets. I ran that pump two days ago for over an hour & and a half non-stop in 85F temperatures. Didn't even stop it to refuel. No way I'd be running 50:1 or higher in that pump.

My Echo trimmers, Lawnboys and chainsaws all get 32:1. My two Jonsereds saws are both over 30 years old and my Echo saw is 11 years old. All three have very healthy compression, run great and have seen a lot of service over the years.

If people want to run less oil, it's their choice. New synthetics might provide sufficient protection. However, I use relatively inexpensive conventional two cycle oil that I buy in gallon jugs. It's served me well over the years. never had an engine fail yet.

When people have put 30 years or more running their two cycle engines at 50:1 ratios and higher, I'll be interested to hear from them.

 

[Mike72]

Just checked the hour meter on my Lawn Boy 7024,it reads 122.6 hrs. Two of those hours were today in 90 degree temperature. The engine was rebuilt in the winter of 2016, I average 50 hours a season mowing time. This all needle bearing engine (retrofit) has been using 50:1 fuel/oil mix from the very first start after the rebuild. My next tear down is scheduled for 250hrs which should be end of season 2020. I have not removed or checked the spark plug yet,it was installed new at 0 hours. I had to open the muffler at 102 hrs. to replace the exhaust gasket that cracked and found a light coating of soft carbon with only a slight amount around the three ports. I cleaned out the carbon and reassembled. That has been the only engine maintenance so far other than cleaning the air filter.
Based on the above and many previous hours of running experience its no secret that Lawn Boy models with all needle bearings can run on 50:1 with no lubrication problems.

 

[boraticus]

Originally Posted By: Mike72
Just checked the hour meter on my Lawn Boy 7024,it reads 122.6 hrs. Two of those hours were today in 90 degree temperature. The engine was rebuilt in the winter of 2016, I average 50 hours a season mowing time. This all needle bearing engine (retrofit) has been using 50:1 fuel/oil mix from the very first start after the rebuild. My next tear down is scheduled for 250hrs which should be end of season 2020. I have not removed or checked the spark plug yet,it was installed new at 0 hours. I had to open the muffler at 102 hrs. to replace the exhaust gasket that cracked and found a light coating of soft carbon with only a slight amount around the three ports. I cleaned out the carbon and reassembled. That has been the only engine maintenance so far other than cleaning the air filter.
Based on the above and many previous hours of running experience its no secret that Lawn Boy models with all needle bearings can run on 50:1 with no lubrication problems.


Then why the need for a rebuild? Was something worn out? Did it lose compression?

122 hours isn't a whole lot. I've got hard used two cycle engines going on 40 years old and never been touched still running like new.

Your endorsement of 50:1 ratio isn't a particularly shining example of longevity if you're rebuilding engines with such low hours.

 

[Mike72]

This rebuild came after 6 seasons of use, did not have an hour meter during this time. I felt that was long enough to do an internal inspection and see if the 50:1 ratio was causing any problems, it was not.

 

[boraticus]

Originally Posted By: Mike72
This rebuild came after 6 seasons of use, did not have an hour meter during this time. I felt that was long enough to do an internal inspection and see if the 50:1 ratio was causing any problems, it was not.




Maybe I'm old school but generally speaking if an engine is running as intended and not showing any symptoms of failure of any kind, a rebuild isn't necessary.

I own two 1970s Lawnboys and they're completely original and still running as intended. I opened them up to take a look, put them back together, did a compression test and they were at spec. Those are forty year old engines with who knows how many hours on them running very well.


Still don't understand the reason to rebuild it if there was no wear?

 

[Darkfire]

Originally Posted By: racin4ds
Yes, 40:1 is the leanest you should run any 2 stroke, especially an air cooled engine. It has been proven time and time again that more oil increases ring seal, bearing life and overall power and longevity. Don't fall for the EPA hype and run 50:1 or more, you're just asking for trouble down the road.

There are several articles on the web that validate testings ratios down to 15:1 and the engines gain HP. proving better ring seal and better combustion.

The 50:1 suggestions is the same as the push to run 0W20 in everything... its NOT there to increase durability/longevity, I can assure you of that!

In my small OPE engines (25cc) I have run 20:1 Mobil Racing 2T, but have now actually gone back to a quality dino oil (Pennzoil Air Cooled (also 20:1) (not the "outdoor" labeled bottle) for what I believe will afford better rust/corrosion protection than an ester like M1 Racing. Was looking at my backpack blower today and saw rust at the end tip inner area of the exhaust (hopefully nothing beyond that developed any rust on it--I live in a high humidity environment). I add in a half ounce of MMO per gallon and 1/8 of an ounce of RLI Bio-Plus (not sure if this is really worthwhile or not), to non ethanol 92 octane. I have a 10546 1997 Lawn Boy that I give 25:1 Mobil 1 Racing mixed in 100LL, with the aforementioned additives as well. I will never use less than 25:1 in any 2 cycle engine.

 

[Mike72]

Originally Posted By: boraticus
Originally Posted By: Mike72
This rebuild came after 6 seasons of use, did not have an hour meter during this time. I felt that was long enough to do an internal inspection and see if the 50:1 ratio was causing any problems, it was not.




Maybe I'm old school but generally speaking if an engine is running as intended and not showing any symptoms of failure of any kind, a rebuild isn't necessary.

I own two 1970s Lawnboys and they're completely original and still running as intended. I opened them up to take a look, put them back together, did a compression test and they were at spec. Those are forty year old engines with who knows how many hours on them running very well.


Still don't understand the reason to rebuild it if there was no wear?



At the beginning of the six years (2010) the reason for the rebuild was to retrofit a needle bearing and thrust bearing into the crankcase replacing the bronze bushing. I then started using 50:1 mix and after six seasons running decided to open the engine and inspect the work I did.




By the way is your name Thomas or are you just looking for information?

 

[gathermewool]

Originally Posted By: Srt20
Originally Posted By: Cedarshark
I own 30 chainsaws and buy/rebuild and sell them. Your question(OP) is easy to answer. Any 2 stroke motor can be burned up at ANY oil to fuel ratio if it becomes leaned out at the fuel to air ratio. The fuel to air ratio is controlled by the high and low jets in the carb. So if you cannot adjust the carb for the particular mix you are running, my suggestion is to use the mfg suggested ratio. I tune with a tach made for 2 strokes and modern saws will run between 12,000 -14,000 rpm at WOT.


Have you ever seen an engine that calls for 50:1 ratio burn down at a 32:1 ratio?? Just curious since its only 1.4oz more oil PER GALLON....

If it lean burns down at 32:1 I promise you it would also burn down at 50:1.

Also, if it has carbon build up(which is a crock too) at 32:1, it will have the same at 50:1.



It's better to compare the effective ratio of gas/oil, instead of thinking of it from the point of view that the gallon is some huge unit of volume. 1.4 oz. may not seem like much, compared to 1 gallon of gasoline; however, a change in ratio from 50:1 to 32:1 is HUGE. The comparison of 4.0 oz of oil (32:1) to 2.6 oz of oil (50:1) is also the same amount of HUGENESS (exactly, if you can believe it!)

From 32:1 to 50:1 is a 54% increase in the amount of oil added!

From 40:1 to 32:1 is a 25% increase in the amount of oil added.

Originally Posted By: Mike72
Originally Posted By: boraticus
Originally Posted By: Mike72
This rebuild came after 6 seasons of use, did not have an hour meter during this time. I felt that was long enough to do an internal inspection and see if the 50:1 ratio was causing any problems, it was not.




Maybe I'm old school but generally speaking if an engine is running as intended and not showing any symptoms of failure of any kind, a rebuild isn't necessary.

I own two 1970s Lawnboys and they're completely original and still running as intended. I opened them up to take a look, put them back together, did a compression test and they were at spec. Those are forty year old engines with who knows how many hours on them running very well.


Still don't understand the reason to rebuild it if there was no wear?


By the way is your name Thomas or are you just looking for information?


Thomas? Did you mean George?

Wait; never mind, that doesn't work lol

 

[Srt20]

Originally Posted By: gathermewool
Originally Posted By: Srt20
Originally Posted By: Cedarshark
I own 30 chainsaws and buy/rebuild and sell them. Your question(OP) is easy to answer. Any 2 stroke motor can be burned up at ANY oil to fuel ratio if it becomes leaned out at the fuel to air ratio. The fuel to air ratio is controlled by the high and low jets in the carb. So if you cannot adjust the carb for the particular mix you are running, my suggestion is to use the mfg suggested ratio. I tune with a tach made for 2 strokes and modern saws will run between 12,000 -14,000 rpm at WOT.


Have you ever seen an engine that calls for 50:1 ratio burn down at a 32:1 ratio?? Just curious since its only 1.4oz more oil PER GALLON....

If it lean burns down at 32:1 I promise you it would also burn down at 50:1.

Also, if it has carbon build up(which is a crock too) at 32:1, it will have the same at 50:1.



It's better to compare the effective ratio of gas/oil, instead of thinking of it from the point of view that the gallon is some huge unit of volume. 1.4 oz. may not seem like much, compared to 1 gallon of gasoline; however, a change in ratio from 50:1 to 32:1 is HUGE. The comparison of 4.0 oz of oil (32:1) to 2.6 oz of oil (50:1) is also the same amount of HUGENESS (exactly, if you can believe it!)

From 32:1 to 50:1 is a 54% increase in the amount of oil added!

From 40:1 to 32:1 is a 25% increase in the amount of oil added.

Originally Posted By: Mike72
Originally Posted By: boraticus
Originally Posted By: Mike72
This rebuild came after 6 seasons of use, did not have an hour meter during this time. I felt that was long enough to do an internal inspection and see if the 50:1 ratio was causing any problems, it was not.




Maybe I'm old school but generally speaking if an engine is running as intended and not showing any symptoms of failure of any kind, a rebuild isn't necessary.

I own two 1970s Lawnboys and they're completely original and still running as intended. I opened them up to take a look, put them back together, did a compression test and they were at spec. Those are forty year old engines with who knows how many hours on them running very well.


Still don't understand the reason to rebuild it if there was no wear?


By the way is your name Thomas or are you just looking for information?


Thomas? Did you mean George?

Wait; never mind, that doesn't work lol


The question is still the same.....

Have you, or anyone else for that matter, EVER seen an engine that calls for 50:1 ratio have a lean burn down because it was run at 32:1 mix??

Again, if it burns down at 32:1, it would burn down at 50:1.

 

[ARB1977]

50:1 is recommended in my Sthil. Stared running Amsoil Saber between 80-100:1. Doesn’t skip a beat.

 

[andyd]

Both of my weed wackers are specced for 50:1. Both run just great on Valvoline Universal 2 stroke oil mixed at 32:1 40 yr old Stihl saw specced for 40:1. Never have had a carbon problem or a fouled plug. 32:1 is a safety precaution. So far, my 2 stroke has had no oil related failures. So I guess it works. Thats the other thing, I mix only a gallon at a time.Not gonna mix 3 different fuels.