2 Stroke Oil

[Goody]

Hi all, new here and just purchased a new boat. Ive been 12ft Tinny man for a while now, 3.8 metre Quintrex Bass with with a '99 25 HP Johno on the back. Stepped up to a 5.3 Mt Whittley Impala with a 2002 90Hp  Mercury just last week. The bloke I bought it off said ONLY use Castrol 2 Stroke oil in her, as that is what his motor mechanic told him. Now Ive never been a brand whore in my life but what do you blokes reckon about that? Ive run my non premixed Johnno on Valvoline oil with no drama's and when I priced the Castrol oil it was probably $10 more for 4 litres. Is there $10 diffrence in the 2 oils or am I just being a tight arse. Both oils have the same specs, even the Western Gulf one does. Are oils just oils?

Cheers

Goody 

[Tybo]

I've used Valvoline two-stroke oil in my boat for 5 years now, over 300 hours and never had a problem, compression is perfect. I'd like to use Penrite as that what I use in my cars, but Penrite two-stroke is hard to come by and double the price. Valvoline is readily available and fairly affordable.

I'm sure mechanics and industrial chemists can tell the difference, but I believe as long as it is made to NMMA TC-W3 spec, then you're safe. My only suggestion is when you decide, always try and use the exact same product from then on.

[Gad]

I`m sure there will be more knowledgeable people than me comment on this question, but here`s my 5cents worth of what little I  have been told.

 

Starting out with the base oil, mineral, synthetic, semi synthetic etc, manufacturers then add a variety of additives to help the oil achieve its stated functions. The additives can range from approximately 25% of the total volume of the oil down to 8% of the volume.

 

These additives can include detergents, dispersants, friction modifiers, oxidation inhibitors and anti wear agents, extreme pressure additives etc. Now the formulas and base materials used with the additive each manufacturer uses may not be identical with ones others use, in other words some oils are incompatible because of differences in additive chemistry.

 

When a new engine starts out,through the heating and burning stages of the petrol/oil in the cylinders a thin glaze is baked onto the cylinder walls, contiuously using the same brand and viscosity of oil there is obviously no incompatiblity. A change to a different brand of oil MAY bring an incompatible additive chemistry reaction. This may cause the new oil to want to strip the old glaze down while building it`s own glaze up, and what happens to and where does the residue of the stripped down glaze go.

 

This may or may not be a concern in the short/long term, but for the sake of $10 ?

 

Yes, I am aware that some people do chop and change their oils when they cant find their normally used oils but that could be the difference between an outboards life of 10+ years and one of 20+ years.

 

If you do change oils just use that brand oil only for the time you own it.  

[Binder]

Won't be an issue for much longer! 2 strokes going the way of the dodo in a couple years, then it will only be wearing out what people already have.

Using same oil Good in theory, but good luck buying the same oil for that length of time, they are continually changing the formulation of products, introducing new ones, discontinuing old ones etc.

[Terry H]

For what it's worth, I have heard of guys have issues with the Valvoline fouling up plugs. No idea on the level of truth in this, but reading other forums, others have suggested the TC-W3 spec is pretty old and loose. Also that the Valvo is probably just meeting spec, rather than exceeding like some other products.

Subjective of course, but I feel my outboard is certainly running a bit cleaner and nicer on the Merc/Quintrex stuff than the Valvo (touch wood). 

[Goody]

Well thanks guys, it does make sense to stick to what has been used prior and $10 is cheap insurance. The motor has 338 hours on it and the bloke I bought it off has had it for 9 years, plus about 4 years also by the original owner, dont know what he used at first. Thanks all, great advice, cheers

[Gad]

On ‎10‎/‎05‎/‎2017 at 7:37 PM, Binder said:

Using same oil Good in theory, but good luck buying the same oil for that length of time, they are continually changing the formulation of products, introducing new ones, discontinuing old ones etc.

from past experience I`ve found,when a manufacturer has discontinued a particular line a compatible one is available, just a matter of asking about it.