Synthetic oil or not?

[bertsmobile1]

Bange,
What you are missing is the fact that the API ( or any other standards association ) ratings are assigned according to how the oil ranks during a series of standard tests .
Almost none of these tests are actual in use engine tests.
And all of them were designed to test standard refined mineral oils, not synthetic oils created from gases.
Synthetics do substantially better in the 3 ball test and have a substantially lower ash content

 

[7394]

?

 

[Bange]

Well, I see this as a standard test for everyone... if the test was not satisfactory the oil manufacturers themselves would make a fair complaint or denunciation.
I don't know the 3 ball test and I don't even have a way to analyze ash content... do you? Tell us how.
Comparing the evolution of mineral, semi-synthetic and synthetic, it is obvious that the synthetic has better performance, hence it receives a higher classification (above SN) and there is no mineral of the same classification to compete.
But I believe this is just a market strategy or investment in development and a lot of marketing, because synthetic oil is cheaper because it is made in the laboratory... and research with minerals stopped or stopped being interesting.
The use of a new word (synthetic, magnetic, molecular...) is a huge leverage for sales.
There's a lot of money rolling in this industry... if synthetic were top of the top, why would manufacturers like B&S still nominate the mineral?
In the chart I posted, the Synthetic SAE 5W30 meets all temperature ranges, why others?

 

[bertsmobile1]

Because there is no benefit in using an oil that is specified way above what is needed to operate the engine
Again I tell you these are MOWER ENGINES and mower engines are the cheapest engines it is possible to make because Joe Public will not pay for quality engines which is why Honda abandoned the market where it has the reputation of being the best engine available .

Next synthetic oils are far more expensive to make because they are made from LPG and you need a lot of LPG that could have been sold for fuel to make oil .
They are not made in labs, they are made in refineries , just the same as mineral oils are distilled from crude.

Semi synthetic oils are made like flour and a lot of other things where the crude is broken down into all of it's parts then reassembled back into lubricating oil rather than just breaking crude down into lubricating oil and leaving the bits you did not need behind in the oil .

120 octane avaition fuels are "better" than pump petrol.
Race petrol is better than pump petrol
But neither of them will make my mower run any better than std 90 grade pump petrol

 

[Bange]

I partially agree with you and would like more information on making a synthetic... but as far as I know semi-synthetics are just a mixture of two different compounds, one mineral and one synthetic + additives.
When you talk about benefits, what exactly are you referring to? Of course it's not making a ferrari out of the Beetle... would it be for the pocket, for the engine?
The classification is the same... they all meet the needs of the engine and the manufacturer B&S makes no distinction, if one is more expensive than the other or exceeds the need... B&S only puts the cards on the table, if the operation is in the range from -30 to 40°C expensive or cheap or exceeding, you'll have to use the synthetic SAE 5W30... do you have another one?

Fuel is another thing... you forgot about nitro...

 

[bertsmobile1]

Full synthetics are made by converting a gas, usually an ethane or methane derrivative into a liquid.
However the gas has to come from somewhere
Most of it is a byproduct of oil refining, but some is natural gad or coal field gas.
Usually it is a case of forcing the gas to react with a solid to make a liquid .

Now it is a moot point as to weather turning crude oil into a gas then turning that gas back into a liquid is actually creating a synthetic oil or not in comparrison to turning mined LPG or fracked Coal Seam gas into a liquid .
In fact they all are derived from similar geological deposits in the first place.

Normally crude is broken down as cheaply as possible into bulk derriatives that are not a single "pure" substance.
Bitumen contains thousands of different compounds as does petrol as does lubricating oil
In theory you can strip the oil down into all of the base molecules , then recombine them into the exact product that you want.
This is the definition of a semi - synthetic because everything it is made from was either a liquid or solid and not a gas.
THis is exactly what is done with corn & wheat to make the various corn & wheat based products and different types of flour.
Oils made this way are a lot more expensive than oils just refined from crude by removing the dissolved gasses and some of the impurities that are not wanted for the particular oil.
Easy to understand example
Heavy lubricating oil has sulphur added to it for extreme pressure resistance, so it would be counter productive to spend lots of time effort & money to remove the sulphur when you are going to add more .
Two stroke oil is burned fully or partially in the cylinder so for it you need to remove all of the sulphur .

 

[Bange]

I was wrong with regard to the cost of producing synthetics... in fact they are produced from additional processes to obtain so-called mineral oils (obtained in the first stratification of crude oil), so they add more value to their production and consequently higher final cost of the product.
A relatively easy-to-understand material can be viewed at: https://www.cyclon-lpc.com/en/how-are-lubricants-produced/

 

[slomo]

2-pack of racing oil.

 

[Bange]

Around here we use this oil as biodiesel, produced after being used in frying.
Much cheaper, less polluting and with the same efficiency as regular diesel.

 

[bertsmobile1]

You have to strip the fats out of the oil first or you will end up with serious pump problems, particularly on varying stroke length piston pumps.
The up side is the fats are really good feed for cows & horses .
And caster oil is what you use for racing on .
A few around here are trying canola as a two stroke oil and a lot have been using veggie oil as a chain bar lubricant.
However the latter case you run the risk of of a bio fire if you have a big pile of sawdust .