2-Stroke mix ratio for '91 snowblower

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Everthing I've read on 2 cycle oil - here's my opinion:

viscosity:
injector type machine - 20W (solvent added)
premix type: 30W; 40W; 50W
50W mostly for road racing wide open throttle all the time, most heat.
castor-heat seeking
synthetics- runs away from heat
dino- most carbon residues, ring stiking.
Ring sticking is the enemy.
Skirt deposits are the enemy.
I use an oil that burns clean and has a small amount of castor for heat and high rpm protection.
Oils claiming to meet all ratio needs are just 20W injector oils.
Fuel/Oil ratio:
for all viscosities- 20:1 best ring seal most power, just TUNE the carb for the 20:1 ratio(hair richer).
If using a dino no matter the ratio you must decarbon more often.
 
it depends are you going to use an oil that is rated at 100:1 or a lesser quality oil
a oil that is rated as JASO FB should probably be used at 32:1 or more but a JASO FD or ISO-LEGD rated oil should be perfectly safe at 50:1 as this is what it has been designed and tested for
the point is if you buy cheap low/non rated 2 stroke oil follow the engines recommendation if you buy more expensive higher rated oils you are wasting your money if you don't follow the oil manufactures recommendations
 
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Originally Posted By: hate2work
Originally Posted By: boraticus
If you have multiple two cycle machines with different oil ratio requirements, always adjust the oil ratio toward the higher oil concentration. For instance, if you have a 32:1 machine and a 50:1 machine, mix up a batch of 35 or 40:1 to use in both. Not only will it provide more lubrication, higher oil concentrations in the 32:1 range will produce more power.


This is wrong. Again, engines don't have ratios, the ratio is determined by the oil.

And what makes you think that more oil in the fuel produces more power? The exact opposite is true, because more fuel to burn equals more power.


100% incorrect information. I will not spend time addressing every point.

Each engine design and internal load factors are different. The mixture ratio is determined by the engineers who design the product. Can you imagine using a really high quality synthetic, mixed at 100 to 1 (yes, a viable ratio in some modern engines), in a particular engine that was constructed with a sleeve con-rod large end bearing??? Near instant failure would result.

And, yes, more oil makes more power, properly jetted, of course.
 
From many of the above comments regarding oil manufacturers suggested oil ratios superseding those of engine manufacturers, one must question why an engine manufacturer would prescribe a specific fuel to oil ratio, without provisions to ignore same because some oil manufacturers claim their oils provide protection at higher ratios?

I've yet to read a two cycle engine manual that states that we have such an option. Has anyone here bought a piece of two cycle equipment that has a manual that states recommended oil ratio may be ignored if using "X, Y and Z" oil?

The only variance prescribed by an engine manufacturer was to mix a bit more oil if working in higher ambient temperatures or working the engine hard for long durations. I've yet to see a recommendation specifying less oil.

This is pretty much a no-brainer.

However, those who have drunk the koolaid can't seem to relinquish their views that their expensive two cycle oil companies have absolute authority over the lubrication needs of every engine made....

News flash guys.... It's nothing more that a sales pitch to get you to pay four or five times more than you need to for their product!!!
 
Shindaiwa manuals for their 2 stoke products state to use shindaiwa brand oil at 50:1 and other oils at 25:1 so that says to me that it is the grade of oil that they think determines the mix not their engineering otherwise they would say to use only a 25:1 mix note Shindawai one oil is i believe a JASO FC ISO-LEGD grade oil it may even now be a JASO FD grade oil
 
Originally Posted By: iand
Shindaiwa manuals for their 2 stoke products state to use shindaiwa brand oil at 50:1 and other oils at 25:1 so that says to me that it is the grade of oil that they think determines the mix not their engineering otherwise they would say to use only a 25:1 mix note Shindawai one oil is i believe a JASO FC ISO-LEGD grade oil it may even now be a JASO FD grade oil


If you believe what you say, why wouldn't the engine manufacturer just say "mix oil as per oil manufacturer instructions" ? Why would they confuse matters by issuing their own mixing instructions?

Shindaiwa have decided what oil ratio(s) the engine needs to have to operate. They have specified the oil ratio for their brand of oil and have "DOWN-GRADED" other oils. I would say the down-grade is more to market their brand and any other oil with similar specifications would work just fine.

Please tell us, did Shindaiwa indicate anywhere in their manual to mix oil above 50:1?
 
Hello Bitogers:

Bought one of the last Toro 221Q two stroke snow blower's during a summer clear out sale. Recommends 50:1.

I picked up a six pack of Stihl HP Ultra full synthetic to use in it. Surprised when I read the label on back stating it's only a JASO FB oil. Thought this was a top-line oil and would be rated higher. After this stash of Ultra is gone, what brand available (at retail/ope) would have a higher rating?

Plan to run a 40:1 ratio for first couple of tanks, then go to 50:1. See any issues with this strategy? I'm thinking that the EPA had their hand in running less oil in two strokes to reduce pollution.

Sorry for partially hijacking the thread.

Thanks for any advice you guys can provide.
Joe
 
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I have a new 221QE. I run conventional Motomaster two cycle engine oil from CTC in it and everything else I own, and I have lots of two cycle stuff.

If the Stihl oil can provide excellent lubrication for chainsaws spinning at 12000+ rpm, I think you should be confident that it will also provide excellent lubrication in an engine running at a measly 4000 rpm tops, particularly in a cool environment. Considering you're running the machine in cooler temperatures, I'd say 50:1 would probably be preferred.
 
Originally Posted By: boraticus
I have a new 221QE. I run conventional Motomaster two cycle engine oil from CTC in it and everything else I own, and I have lots of two cycle stuff.

If the Stihl oil can provide excellent lubrication for chainsaws spinning at 12000+ rpm, I think you should be confident that it will also provide excellent lubrication in an engine running at a measly 4000 rpm tops, particularly in a cool environment. Considering you're running the machine in cooler temperatures, I'd say 50:1 would probably be preferred.


boraticus:

Should I run it at 50:1 out of the box? I thought maybe during initial break-in, a little extra oil would help. At least for the first tank.
Thoughts?
 
Originally Posted By: Joe72Mart
Originally Posted By: boraticus
I have a new 221QE. I run conventional Motomaster two cycle engine oil from CTC in it and everything else I own, and I have lots of two cycle stuff.

If the Stihl oil can provide excellent lubrication for chainsaws spinning at 12000+ rpm, I think you should be confident that it will also provide excellent lubrication in an engine running at a measly 4000 rpm tops, particularly in a cool environment. Considering you're running the machine in cooler temperatures, I'd say 50:1 would probably be preferred.


boraticus:

Should I run it at 50:1 out of the box? I thought maybe during initial break-in, a little extra oil would help. At least for the first tank.
Thoughts?


It's not necessary. If it makes you feel better, go ahead, run it with a 32:1 to 40:1 ratio to break it in, then switch to 50:1. Four thousand rpm isn't much more than a high idle for a two cycle engine. I've got two other SS machines powered by Tecumseh two cycle engines. They're supposed to have 40:1 mix. I also have older machines such as chainsaws that are supposed to have 25:1 mix. I keep a container mixed at approx. 32/35:1 that I use in all of my equipment. If I'm going to run my saws long and hard, I'll mix them closer to their recommended mixture. Otherwise, everything gets the same fuel.

Just for fun, I've over-ridden the governors on the two Tecumseh two cycle snow blowers. I ran the 1997 Craftsman machine for most of last winter at 6000+ rpm when moving snow. I have a string attached to the governor and operate it like a throttle. It's like running a chainsaw. Spin it up when pushing it into the snow and back off the throttle when not under load. That old Craftsman machine is a lot of fun to use and the higher speeds certainly help it throw snow.

The 221QE is a serious SS machine right out of the box. Check your rpms with an electronic tach to ensure it's running at around 4000 rpm. It's permissible to run it at 4100 but I found that a bit too fast when trying to control the machine on a 10% downhill grade. Going up, no problem. Slowing the engine down to 4000 made enough of a difference to matter. If you're working on a flat grade, set it to 4100 and go to work.

I'm of the belief that a bit more oil is much better than a bit less. If you have nothing but 50:1 equipment, run that ratio. Nothing wrong with that Stihl oil either.
 
Originally Posted By: boraticus
Originally Posted By: Joe72Mart
Originally Posted By: boraticus
I have a new 221QE. I run conventional Motomaster two cycle engine oil from CTC in it and everything else I own, and I have lots of two cycle stuff.

If the Stihl oil can provide excellent lubrication for chainsaws spinning at 12000+ rpm, I think you should be confident that it will also provide excellent lubrication in an engine running at a measly 4000 rpm tops, particularly in a cool environment. Considering you're running the machine in cooler temperatures, I'd say 50:1 would probably be preferred.


boraticus:

Should I run it at 50:1 out of the box? I thought maybe during initial break-in, a little extra oil would help. At least for the first tank.
Thoughts?


It's not necessary. If it makes you feel better, go ahead, run it with a 32:1 to 40:1 ratio to break it in, then switch to 50:1. Four thousand rpm isn't much more than a high idle for a two cycle engine. I've got two other SS machines powered by Tecumseh two cycle engines. They're supposed to have 40:1 mix. I also have older machines such as chainsaws that are supposed to have 25:1 mix. I keep a container mixed at approx. 32/35:1 that I use in all of my equipment. If I'm going to run my saws long and hard, I'll mix them closer to their recommended mixture. Otherwise, everything gets the same fuel.

Just for fun, I've over-ridden the governors on the two Tecumseh two cycle snow blowers. I ran the 1997 Craftsman machine for most of last winter at 6000+ rpm when moving snow. I have a string attached to the governor and operate it like a throttle. It's like running a chainsaw. Spin it up when pushing it into the snow and back off the throttle when not under load. That old Craftsman machine is a lot of fun to use and the higher speeds certainly help it throw snow.

The 221QE is a serious SS machine right out of the box. Check your rpms with an electronic tach to ensure it's running at around 4000 rpm. It's permissible to run it at 4100 but I found that a bit too fast when trying to control the machine on a 10% downhill grade. Going up, no problem. Slowing the engine down to 4000 made enough of a difference to matter. If you're working on a flat grade, set it to 4100 and go to work.

I'm of the belief that a bit more oil is much better than a bit less. If you have nothing but 50:1 equipment, run that ratio. Nothing wrong with that Stihl oil either.


Hi boraticus:

I also have multiple two stroke engines, each with their own oil recommendations. Three LawnBoys want 32:1, two old mopeds same, new Tomos wants 50:1 also Toro 221QE at 50:1. And an old Toro 200S that still going strong at about 25 yrs old.
Question about my new 221QE: I have an optical rpm tool. How much of the plastic skins do I have to take off to measure rpms? Is it set from the factory to run 4k rpm? If not, how do I adjust? Change tension on governor spring? Probably won't try this until out of warranty, but still would like to know the procedure you use.
thx, BTW I enjoy your two stroke postings.
Joe
 
Originally Posted By: boraticus
Originally Posted By: iand
Shindaiwa manuals for their 2 stoke products state to use shindaiwa brand oil at 50:1 and other oils at 25:1 so that says to me that it is the grade of oil that they think determines the mix not their engineering otherwise they would say to use only a 25:1 mix note Shindawai one oil is i believe a JASO FC ISO-LEGD grade oil it may even now be a JASO FD grade oil


If you believe what you say, why wouldn't the engine manufacturer just say "mix oil as per oil manufacturer instructions" ? Why would they confuse matters by issuing their own mixing instructions?

Shindaiwa have decided what oil ratio(s) the engine needs to have to operate. They have specified the oil ratio for their brand of oil and have "DOWN-GRADED" other oils. I would say the down-grade is more to market their brand and any other oil with similar specifications would work just fine.

Please tell us, did Shindaiwa indicate anywhere in their manual to mix oil above 50:1?

they issue there own oil ratio because they want you to buy there oil and most manufacturers recommend there own oil at 50:1 and other oils at 25:1 because they want you to buy there oil and they also know the actual rating of there oil
if they know there oil is rated at the top rating of cause they will "down grade" other oils most of which don't have as high a rating
and my point was that any oil of the same or a higher rating will supply the same protection
no shindaiwa do not recommend higher mixes they market an oil the should be mixed at 50:1 why would they recommend an oil that can be mixed above this when it would be recommending a rival product
 
In order to access the spark plug lead to attach the wire for the tach, I removed the top cover only and it comes off fairly easily. Lots of room in there. You might not have to take the top off. The side panel for the drive belt comes off easily enough and you should be able to put the reflector tape on the PTO there. Either way, you should confirm the engine speed. I know mine was lower than spec when I bought it. I believe the correct engine speed is between 4000 to 4100 rpm. If it's adjusted within those parameters, there shouldn't be a warranty issue.

Adjusting the rpm is very easy. There is a metal tab near the carb with the governor spring attached to to it. By bending the tab you can increase/decrease engine rpm. Can't recall which way to bend it but if you pull on the spring while the engine is running, you'll either speed it up or slow it down. That will tell you which way to bend the tab.
 
"why would they recommend an oil that can be mixed above this when it would be recommending a rival product"

Could it be possible that they don't recommend higher ratios because it may not be good for the engine?

For people who are of the belief that the oil manufacturers determine what ratio to mix their products with fuel, I pose these questions:

What is their basis for making their recommendations?

Do they test every engine manufactured and/or have the engineering data for every engine made?

Do the oil manufacturers recommended ratios supersede the engine builders specified mixing ratio?

Will the engine manufacturers warranty cover a damaged engine that had been run with an oil ratio mixed thinner than their instructions?

Do engine manufacturers operating manuals state anywhere in their literature "Mix oil as per oil manufacturers instructions." ?
 
Here's how I interpert all this:

Oils that are blended to a standard--TCW3, ISO-EGD/JasoFD, etc. will all be about the same. A 50:1 with brandA will be about the same as 50:1 brandB, same for 32:1, 16:1, etc.

The engine manufacturers give the mix ratio needed with an oil that meets a recognized standard.

When an oil is blended outside a standard--a lot of the 100:1 oils--it is likely more concentrated (cut with less solvent) and therefore less oil can be used.

However, this does not address the differences in engines--an engine that specified 50:1 with a standardized oil may be great with a more concentrated oil at 100:1, but an engine that needed 32:1 with a standardized oil may not be OK.

Personally I recommend statying with standardized oils and mixing to manufacturer's ratios.
 
usually you will find that the manufacturers who recommend a oil mix of 50:1 are recommending an oil of JASO FC ISO-LEGD or higher specification while those who recommend higher oil concentrations don't actually list a specification and are basing there recommendation on low grade oils so if you are going to mix to the manufactures unspecified grade oil mix just buy the cheapest stuff out there as using a high grade oil at higher ratio is just a waste
 
Actually the fuel mixture does affect the jetting. The oil takes up volume in the fuel. The jets meter a specific amount of fuel mix. If that mix has more oil then there is less fuel for the same amount of mix. Just to make the math simple let's say we take 16-1 and 32-1 Mix. There is a 3% more oil by volume on the 16 mix so you are getting a 3 percent leaner mix. Now going from 16-1 to 100-1 there is almost 6 percent fuel. That means going with less oil richens the fuel mixture (with today's Lean epa regs its probably good as there lean to start with). Also on a small motor that little change can make a huge difference.

So by going to a mix with less oil it richens the fuel to air mixture.
 
Originally Posted By: bugman53
Actually the fuel mixture does affect the jetting. The oil takes up volume in the fuel. The jets meter a specific amount of fuel mix. If that mix has more oil then there is less fuel for the same amount of mix. Just to make the math simple let's say we take 16-1 and 32-1 Mix. There is a 3% more oil by volume on the 16 mix so you are getting a 3 percent leaner mix. Now going from 16-1 to 100-1 there is almost 6 percent fuel. That means going with less oil richens the fuel mixture (with today's Lean epa regs its probably good as there lean to start with). Also on a small motor that little change can make a huge difference.

So by going to a mix with less oil it richens the fuel to air mixture.


Agreed.

It richens the fuel mix but what does that same ratio do for lubrication? I'd rather have a slightly leaner fuel mixture with better lubrication qualities rather than the other way around.

Let's not forget that little bit of oil in the fuel is lubricating everything from crank bearings, wrist pin and big end bearings as well as the cylinder. More wear will result as the oil content is reduced in the fuel mix.
 
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