What's the difference?

snowleopard

snowleopard

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What\'s the difference?

Valvoline 1 litre Motorcycle 2-stroke oil: £3.99
Valvoline 1 litre Outboard 2-stroke oil: £5.99

So what's in it to make it 50% more expensive?
 
Re: What\'s the difference?

I didn't look at the details but the Valvoline.co.uk website has the tech specs for its products. I suspect they would claim they use different additives.
 
Re: What\'s the difference?

The outboard oil will be for water cooled engines It should be to TCW-3 specification (TC =two cycle, W = water cooled, 3 is the latest spec.)

Motor cycle oil, like that for 2 stroke garden machinery, is presumbably for air cooled engines or are motor bikes water cooled ?

There is at least a difference in viscosity between oils for water cooled and air cooled engines, presumably reflecting the fact that air cooled engines run hotter than water cooled ones. There may well be other differences as well as viscosity.

Of course outboard oil is going to cost more. Would you expect otherwise. The volume used will dictate that if nothing else.
 
Re: What\'s the difference?

any decent 2-stroke oil will perform the following functions (so will any decent oil, come to that ! /forums/images/graemlins/blush.gif)

1 Detergent/dispersant additives- used to maintain engine cleanliness, keep the various contaminants in a fine suspension and prevent them from settling out on vital engine components.

2 Rust and corrosion inhibitors- added to protect the engine from water and acids formed as combustion by-products.

3 Antioxidants- added to inhibit the oxidation process, which can result in oil thickening and sludge formation.

4 Anti-wear additives- form a film on metal surfaces to help prevent metal-to-metal contact.

5 Viscosity modifiers and pour point depressants- help improve the flow characteristics of motor oil.

The API (American Petroleum Institute) rating has a two letter code. The first letter is S for spark ignition engines, or C for compression / diesel engines. The letter after the S shows the performance level (later the letter, the better). The current one is API SM, IIRC.

Oils and distillates are "tuned" for the intended service environment, and such components as % sulphur, API gravity rating, minimum flash point, lead content, viscosity, pour point, vanadium content, freezing point, cetane rating, can be easily, but expensively, altered in the refining process.

Even a "single market segment "-specific oil (e.g. outboard oil) will be differently composed, depending on such matters as anticipated ambient temperature or geographical market location. National legislation e.g. concerning exhaust smoke, will also affect the blend characteristics. Other factors will be the kind of petrol used in the base mix, so some 2 stroke mixes will definitely NOT be suitable for use with very high-octane fuel, or methanol/alcohol bases as used in racing, where very special oils and mixes are needed.

Add to that, the need to ensure miscibility with a range of petrols, and suitability for use in both ready-mixed and injection systems, and you can see that though two adjacent cans of oil may seem to do the same job but at a different price, they will be formulated to cope with quite different operating environments. The difference in performance envelope and characteristics is the primary cause of the price differential (though the chandlery or land-based garage may be an influential factor /forums/images/graemlins/grin.gif)
 
Re: What\'s the difference?

[ QUOTE ]
We go round this loop every few months it seems.

[/ QUOTE ]
So if I PM you all my posts before putting them on the forum, will you tell me if they are sufficiently original or have previously been covered among the 430,000 previous posts on this forum?
 
Re: What\'s the difference?

All 2-stroke oil is a complete con. It only has to lubricate for about a millionth of a second as it passes round the engine before being burnt. It's not like oil in a four-stroke, which sits in a sump absorbing corrosive exhaust products and being repeatedly cooked up over a period of months.
I've always used the cheapest oil I can find in any 2-stroke engine I've owned.
 
Re: What\'s the difference?

and while it's waiting to burnt in tank, what it does in the burning cycle (cleaning, lubricity, ...), and what it does to the environment after it has passed through the exhaust ? It all matters, amigo, honestly.
 
Re: What\'s the difference?

So what precisely is it doing in the tank, sitting mixed in petrol waiting for its brief moment of glory? What is a marine two stroke oil doing that an ordinary one isn't?
 
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