Two-Stroke Oils: All the Same?

[B549]

Castrol 2t works for me but that's just my opinion

 

[Hundred Acre Wood]

Castrol 2t works for me but that's just my opinion

First post on an oil thread? The forum will surely welcome a brave person like yourself!

 

[huskihl]

Do you think 50 to 1 lubricates the lower end properly?

Decide for yourself. This is even at 40:1

 

[lone wolf]

Decide for yourself. This is even at 40:1

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Bottom end sure as hell looks dry to me. I wouldn't used it just based on this.

 

[huskihl]

As opposed to 40:1 Red Armor in a strato 362c. The strato runs leaner yet in the bottom end

 

[Hundred Acre Wood]

Decide for yourself. This is even at 40:1

View attachment 1052931View attachment 1052932View attachment 1052933

Thanks for the photos!

Do you see many premature bottom end failures at 50:1? Excessive bearing wear?

 

[huskihl]

Due to heat alone or what else?

As far as why the strato runs leaner in the bottom?
Or why there is oil everywhere with Red Armor?

 

[lone wolf]

As far as why the strato runs leaner in the bottom?
Or why there is oil everywhere with Red Armor?

Why does it run leaner?

 

[huskihl]

Thanks for the photos!

Do you see many premature bottom end failures at 50:1? Excessive bearing wear?

Stihl bearings appear to be pretty good. Or their later philosophy of going with a larger bore and shorter stroke is working better.
I’ve replaced many crankcase bearings, mostly on older saws, although there’s a 661 on the bench now with bad bearings. Seen several 550 and 562’s with bad bearings that were run on Ultra at 50:1.

 

[capetrees]

hmmm ...

 

[huskihl]

Why does it run leaner?

In a traditional 2 stroke (346, 395, 066, MS440…), a portion (20-25?%) of fresh fuel purges spent charge from the cylinder and out the exhaust.

A strato saw packs a layer of fresh air on top of the next incoming transfer charge and purges the spent exhaust out with that first-incoming strato air.

On a conventional 2 stroke, the purging fuel also already went through the bottom end. On a strato, that’s 20-25% less oil and gas that never went through the bottom end

 

[Hundred Acre Wood]

Stihl bearings appear to be pretty good. Or their later philosophy of going with a larger bore and shorter stroke is working better.

Shorter stroke for lower piston and crank velocity seems like a good design choice. Less potential for wear all around. It would be interesting to know if Stihl Ultra formulation is designed around that premise. Meaning it might not be as effective is longer stroke saws like the Huskies? Pure speculation on my part.

edit: The reason I speculate that is because Stihl Ultra is an FB oil and many others are FD with the primary difference between them being detergents, i.e. cleaning parts such as bearings. Dirtier bearings at higher speed = fail? Total speculation on my part as too many other factors like temperature, air filter problems, etc come into play. This is probably completely off base.

I’ve replaced many crankcase bearings, mostly on older saws, although there’s a 661 on the bench now with bad bearings. Seen several 550 and 562’s with bad bearings that were run on Ultra at 50:1.

I've heard folks say "use the oil that was available when your saw was built" which seems sensible as it was probably tested with that oil. But oils aren't available forever, and there's no proof that newer oils aren't just as good and/or better.

 

[huskihl]

Shorter stroke for lower piston and crank velocity seems like a good design choice. Less potential for wear all around. It would be interesting to know if Stihl Ultra formulation is designed around that premise. Meaning it might not be as effective is longer stroke saws like the Huskies? Pure speculation on my part.

edit: The reason I speculate that is because Stihl Ultra is an FB oil and many others are FD with the primary difference between them being detergents, i.e. cleaning parts such as bearings. Dirtier bearings at higher speed = fail? Total speculation on my part as too many other factors like temperature, air filter problems, etc come into play. This is probably completely off base.



I've heard folks say "use the oil that was available when your saw was built" which seems sensible as it was probably tested with that oil. But oils aren't available forever, and there's no proof that newer oils aren't just as good and/or better.

I don’t think it was designed around stroke. Like mentioned, it was designed for a 4 mix.

With certain fuels, it’s nearly as clean as most others. And then the next one has .020” worth of carbon on top of the piston that flakes off and can cause the rings to stick if it lands just right, along with the exhaust port being carboned up to about half of its capacity.

But there are dozens of other oils that don’t seem to care what fuel is run with them and they still leave ample oil behind without building much carbon. Some don’t leave any buildup at all in the exhaust port. Still shiny wet metal after 500 hours.

Ultra appears to be a fine lubricant and works well sometimes. But more often than not, there is a growing layer of black that is common with 40-year-old-oil tech. There are just way better options now at a fraction of the cost

 

[lone wolf]

I don’t think it was designed around stroke. Like mentioned, it was designed for a 4 mix.

With certain fuels, it’s nearly as clean as most others. And then the next one has .020” worth of carbon on top of the piston that flakes off and can cause the rings to stick if it lands just right, along with the exhaust port being carboned up to about half of its capacity.

But there are dozens of other oils that don’t seem to care what fuel is run with them and they still leave ample oil behind without building much carbon. Some don’t leave any buildup at all in the exhaust port. Still shiny wet metal after 500 hours.

Ultra appears to be a fine lubricant and works well sometimes. But more often than not, there is a growing layer of black that is common with 40-year-old-oil tech. There are just way better options now at a fraction of the cost

I havn't used Ultra in years why risk it.

 

[OM617YOTA]

Stihl oil is JASO FB, smells like burning plastic, and you have to go to the Stihl dealer to get it.

There are lots of JASO FD oils that are available everywhere, don't smell like a meth house on fire, cheaper, and don't give me a headache.

 

[KostasVolos]

I've used HP Ultra few years ago in the chainsaws and brushcutters of my small landscaping business.
Nope.
Very expensive ,very "dirty" for the
engine and the muffler ,lots of headaches on the crew.

Husqvarna XP+ we used next ,
was a very good mix-oil.
No smell,clean guts and muffler ,
no bloody headaches and engines
run velvety smooth .
Some of the crew still use it.

Myself and the rest of the crew we jumped on the Amsoil Saber wagon long ago.At 50:1 .
Spark plug is clean ,bluish film of oil is clearly visible covering the skirt of the piston ,with some naptha/kerosene the muffler washes clean ,inside out ,
almost to brand new state.
And can't just be the idea of
at least five of the crew that
the engine seems to run with
more power .Or at least
that sounds like it
has gained power out of nowhere .

Stihl's square 3.3 mm black
nylon weedcutter string is a
bargain for just 55€ the roll
of 228 meters.And quality is tops.
HP Ultra is the exact total opposite...A very expensive green
syrup that pretends to be a 2T mix oil and gives you worse headaches than cheap beer.

 

[bwalker]

I love wives tales. They're really entertaining, but contain very little fact. Yes, it's ashless. That much is true.



Because Stihl tested it in their saws? Or again you're saying they want their product to underperform their competition and fail prematurely? This argument makes zero sense.

Chainsaws ran for decades using nothing but SAE 30. No fancy formulations. No high solvency synthetics. No PAG/PAO. Nothing. It's amazing what you can put in a 2-stroke and still have it run a long life. The wives tale of "designed for 4mix" started at least 10 years ago and it still propagates today. It really needs to end.



Ok, so now we're getting somewhere. We've gotten away from "piles of evidence" to "I had a bad experience". I can relate to that. I had a bad experience with a pair of Redwing boots, but I don't go around saying "All Redwing boots are garbage" and treating that like Gospel that everyone should listen to.

Did you run it at 32:1 or 40:1? What about the results drove you to conclude that Stihl "Ultra is crap oil and there is plenty of evidence of this"?

It's not an old wives tale at all. The 4 mix engine had and still has issues with ash build up on its valves. Hence the ashless Ultra formulation. No other O P E OEM sells an ashless oil. Ashless oils use dispersent additive technology instead of metallic based detergent technology. Ashless dispersent do not function at all over 300 degrees. That's why Uktra builds deposits like crazy. Especially in strato motors or motors like the MS361 with really choked up exhausts.
And yes there are plenty of guys that have posted pictures of ultra ran motors that look absolutely terrible.
In the case of my 361 I had major deposits in the ring area and piston skirt and with under 25 hours of run time.

 

[bwalker]

That's a good question. Stihl certainly thinks so.

I think the reason some people conclude it doesn't lubricate adequately is based on visual perception. They observe its appearance based on other oils they've seen and think "that doesn't look right".

You know what they say though? Looks can be deceiving. How many premature bottom end failures are people experiencing when using it at 50:1? Where are the horror stories of "Stihl Ultra at 50:1 killed my 881 in 100 hours?".

Again, they don't exist. If you know of one, please share.

The bottom end doesn't need gobs of oil. So I'd say sure it may look light, but the wear and tear tells another story. Even Richard Flagg says that in his videos.

"I do see a tiny amount of oil in the crankcase and there's a little bit of sheen on everything, so we're getting adequate lubrication" - 11:13 second mark

With the move to strato technology the numbers of bottom end failures has risen buy quit a bit.
Also consider that a strato engine uses less fuel and thus the engine is less lubricated it males sense.
50:1 ratios came about because the average guy can't tune a carb to save his life and 50:1 resulted in less plug fouling with poor tuning. That and visible smoke with poor tuning and low quality Stihl oil was less.

 

[lone wolf]

With the move to strato technology the numbers of bottom end failures has risen buy quit a bit.
Also consider that a strato engine uses less fuel and thus the engine is less lubricated it males sense.
50:1 ratios came about because the average guy can't tune a carb to save his life and 50:1 resulted in less plug fouling with poor tuning. That and visible smoke with poor tuning and low quality Stihl oil was less.

What ratio you run?

 

[bwalker]

I don’t think it was designed around stroke. Like mentioned, it was designed for a 4 mix.

With certain fuels, it’s nearly as clean as most others. And then the next one has .020” worth of carbon on top of the piston that flakes off and can cause the rings to stick if it lands just right, along with the exhaust port being carboned up to about half of its capacity.

But there are dozens of other oils that don’t seem to care what fuel is run with them and they still leave ample oil behind without building much carbon. Some don’t leave any buildup at all in the exhaust port. Still shiny wet metal after 500 hours.

Ultra appears to be a fine lubricant and works well sometimes. But more often than not, there is a growing layer of black that is common with 40-year-old-oil tech. There are just way better options now at a fraction of the cost

It's all about heat, Kevin. If you don't get above the 300 degree ring belt temp it works like any other ashless oil. IE not great, but serviceable. Once you get above the 300 degree mark problems start to happen.
Then there is the fact Ultra is sold for top dollar, but in reality is a crappy FB quality oil better suited for a boat motor.