Synthetic lubricants vs petroleum lubricants for diesels

Within the past two years, automobiles coming from dealerships have had synthetic oils in them that are recommended to be changes every 10,000 miles rather than the 3,000 miles for petroleum based oils. This year we drained the petroleum oils from a Yanmar diesel and flushed the system with synthetic oils then filled the engine with Mobile 1. The engine appears to run better and has no smoke during cool weather start up. Even though synthetic oils cost more, they are advertised to extend engine life by almost double. Additionally, this is another step away from big petroleum producers and OPEC as synthetics are formulated and made by chemical companies, but stocked by oil company gas stations. The products are available directly from chemical firms in bulk.

 

mmmm... would recommend you reading the small leters on the back of the bottle, the "Synthetc" oils peroleum companies are distributing all around the world, are not 100% synthetic, mostly they are "blendings" made of 20% to 40% synth and the rest is base petroleum oil... (sorry...) the improved part of the tale is the synth part is no more than the old good "aditive" (injector cleaner + anti smoke and some others) another big lie of the Petroleum Companies...
the better the quality, the higher the classification it states in the bottle (API SG, SH...)
Lube oil has a couple major issues:
- Viscosity Loss (as engine produces heat, the carbon chains begin breaking, there is nothing you can do against but changing oil)
- humidity (diesel engines compress air & injects fuel, in that compression, vapour is generated inside combustion chambers & some of it trespass the o-rings mixing with oil)
- carbon (similar thing, carbon is produced during ignition & shoved by o-rings to the oil)
Is a common practice on Petroleum Companies to provide oil analysis to customers, you just may ask for this service (it's free of charge). They will give you the results of any sample you provide.
May I recommend the better option can be using a multigrade base oil (SH class) + some anti smoke + some injector cleaner. the final result would be near the same with a fraction of the cost.

 

Thanks,

Thanks I'll try the other oils and see what happens and the lower price is a plus.

 

you can see the size of the lie on some company lubes datasheets:

http://www.shell.com/home/Framework...en/hojas_de_seguridad/lubricantes_010904.html

http://www.mobiloil.com/USA-English/MotorOil/Oils/Oils.aspx

do you figure why are they offering separate additives for oil? why do you need to add an aditive to an oil that has it?

 

So which boat is yours?

 

Syntetic oils last much longer. They are petroleum oils modified to make the molecules longer. Oil molecules break down with use, get shorter and loose viscosity. If you start with a longer molecule it lasts longer. The additives are anti-foaming, detergents, viscosity modifiers and anti-acids. No lies there.

 

Syntetic oil's come form crude oil just like anny other oil.

When Light fractions like gas, gasoline, diesel and parafine there will be some leftovers at the bottom off the destilation tower.
This can not be destilated because it would require so mutch heat that it would harme the product.
It's there for pumped into a new tower that is operating under vacume so it neads les heat to avaporate. This vacume destilate is what is the base for lubrication oil.
By manipulating the molecules you change the oil's capabiletys and all oil manufactors know how the perfect oil look like and everyone is trying to get as close to it as posible.
Manipulating like this is exspensive so it's normal that they sometime mix it with unmanipulated oil to save cost.
If someone say they are not made from petrolium, they are wrong.

 

Answer on the photo...

 

would you excuse me for correcting you:
what you are figuring is a "cathalytic cracking tower" mostly used as you said, to "crack" longer chained molecules into shorter ones, ok, the only thing you forgot is, shorter chains equals lighter products (ie, you feed the tower with asphalts and get from gasolines,up to gas), never oils. Oil is out on the bottom third part of the first tower... (sorry )
maybe your confusion is on the "multigrade oils", they are blended from different lenght chains (not so different at all), the advantage is as you said, different lenght chains do "break" at different heating points, so, in a medium term, as the first broken are the longest, still "survive unbreakened" the shorter ones, improving viscosity.
Alas, the major need for oil change is rarely viscosity loss (at least in multigrade, classification SH oils), is mainly carbon, as it's isolated molecules some orders of magnitude smaller than oil chains, they live in the "spaces" inter oil-molecules without increasing the whole volume (what a rough descriptoin, sorry again )
Once I've heared that during World War 2, the Germans implemented some kind of "filtering mobile plant" they used to sepparate carbon from oil on tanks and trucks to re-use the same oil (not confirmed)
you can do a home experiment, use a couple metal can's & a coffe paper filter, heat an oil sample (not more than 60ºc & in a ventilated room or outside), slowly pour the heated liquid through the paper filter to the other can, let it go to ambient temp a couple hours, & see the result...

 

Cathalytic cracking is something else. Here you add a catalysator to the crude oil too evaporate out heavy oil fractions. (aluminium oxsyde I belive)

Both gasoline and diesel are oil's

With all respect, Oil's are Hydro Carbones. If you have no Carbon it's all a hydrogen gas.

Remove the carbon and you will only have the hydrogen left. Hydrogen gas is not a good lubricant. There are how ever devices to separate carbon particles from combustion and metal particles from the oil. In this case your engines lube oil consuption will be high enought that it's almoust enough only refilling the oil and not change it.

This is done by sentrifuges withc produce up to 9000g.
You can buy one from www.alfa-laval.com or www.gea-westfalia.com

 

here in GM town ,,,,,,,Dayton Ohio. all the guys at gm are using synthetic , they say the only problem is it is so good that it cleans the engine out and they have leaks ,,,only on old engines, they say that they get are getting an extra 100000 miles and better fuel economy and better engine wear.

 

I hear those storry too. Dirt sealing cracks in gaskets are washed away and you get leak's, but for sealing betwen the liner and pistion it's supreeme.

 

There is little problem with using Syn oil in a daily used work boat.

The hassle is most pleasure boats seldom get used , so the DOWNSIDE of Syn oil becomes a headache.

The Syn oils do NOT give anywhere near the rust prevention that old perto oils do , so should be removed for layup.

Thjs gets really tiedious , although some folks will save the preserving oil and re install it for a few winter storage sints.

Engines designed to use Syn oil will have closer tolerances and different seals and sealing goop unsed on assembly.

I would use a Syn oil in a manual transmission (like a Twin Disc) where there is less hassles with rust and corrosion, but not in my antique 6-71 as it would leak like a sive , and enjoy NO benifits from the pricy oil.

"but for sealing betwen the liner and pistion it's supreeme."

Sorry the rings do the sealing ,
the Syn oil gets scraped off at lower power cost , which is where the "better" economy comes from.


FAST FRED

 

Wrong. If you don't get a oil film on the liners surface your engine would drink oil like a sailor drink rom. If the oil got scraped off you would also have suffing. Only some off the oil is scraped off. betwen the piston ring and the cylinder liner there is something called a hydrodynamical lubrication.

What is the oil's job's?
1.lubricating.
2.cooling.
3.cleaning.
4.sealing.
You all learnet this at a point right?

 

Syntetic oils like Amsoil marine have superior corrosion protection. Fast Fred: syntetic oil is a modified hydrocarbon. Where did you hear it has to be removed for layup? Also, engines are not designed differently for syntetic oil. Any engine can use it as long as it is broken in. Because syntetic oil is so highly lubricant, hard piston rings won't seat properly with it.