Oil for 2 stroke outboards?

Kawasaki,

Well it gave you some late-night typing practice /forums/images/graemlins/grin.gif

I am fairly familiar with small 2 and 4 strokes .....it was just the specific comment concerning the oil altering the fuel/air ratio (to any significant degree) that I was querying-in case I was missing something obscure. Was talking about a difference of perhaps 25:1 rather than 50:1 (old 60s lawnmower used 16:1 .... and you bought it from a pump which mixed anything from 8:1 upwards /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif )

Anyway, seems in this case old fuel WAS the culprit. Also realised (as usual in the middle of the night ... didn't have any wine last night, only beer) that the reason the slow running mixture screw did not appear to have effect was because it's a governed engine, and NEVER normally runs slowly /forums/images/graemlins/frown.gif . Once slowed manually, the mixture screw works as I would expect.


Vic
 
Marine 2 stroke is different from normal Halfords / Off shelf garage stuff. BUT I have used whatever 2 St oil I can get at time ... as most Petrol Stations have it on shelf. If you buy near marina / harbour - often the Petrol St. will have marine stuff as well as normal 2T ... further away only normal 2T ...

Problem for you - if anything goes wrong with it under warranty and the find "other" fuel in it ... ?? Warranty ??
All my O/boards are well past warranty days ... and I use any 2T I can get.

Now experts will shoot me down >....
 
[ QUOTE ]
Now experts will shoot me down >....

[/ QUOTE ] I'm certainly not claiming to be an expert but I suggest that using a (slightly heavier) aircooled engine oil instead of using A TC-W spec oil in a water cooled engine will be less of a problem from the lubrication point of view than doing the opposite ie using a TC-W oil in an air cooled engine.

Quite how much effect it will have on the air fuel mix I am not so sure, despite the fact that I raised that point earlier, especially at the low percentage of oil used in modern outboards The logic is though that a more viscous oil in the mix will make the fuel more viscous and lead to a somewhat leaner mixture being produced by the carb. If both the high and low speed mixtures can be adjusted then adjustment of those will probably suffice. I forget now how much difference in viscosity I found between the two types of oil.

It is interesting to note that the instuction books for my Seagull outboards (1973 and 1974) just recommend a range of ordinary 2 stroke oils (Did the TC-W specs exist then ?) or if not available a non-detergent SAE 30 oil. I used a SAE 30 oil for a while because I had access to a supply. With a 10:1 mix did it smoke!
 
[ QUOTE ]
[ QUOTE ]
Now experts will shoot me down >....

[/ QUOTE ] I'm certainly not claiming to be an expert but I suggest that using a (slightly heavier) aircooled engine oil instead of using A TC-W spec oil in a water cooled engine will be less of a problem from the lubrication point of view than doing the opposite ie using a TC-W oil in an air cooled engine.

Quite how much effect it will have on the air fuel mix I am not so sure, despite the fact that I raised that point earlier, especially at the low percentage of oil used in modern outboards The logic is though that a more viscous oil in the mix will make the fuel more viscous and lead to a somewhat leaner mixture being produced by the carb. If both the high and low speed mixtures can be adjusted then adjustment of those will probably suffice. I forget now how much difference in viscosity I found between the two types of oil.

It is interesting to note that the instuction books for my Seagull outboards (1973 and 1974) just recommend a range of ordinary 2 stroke oils (Did the TC-W specs exist then ?) or if not available a non-detergent SAE 30 oil. I used a SAE 30 oil for a while because I had access to a supply. With a 10:1 mix did it smoke!

[/ QUOTE ]

Funny thing is my Genny instructions specifically say do not use Marine Based 2T ..... so the air-cooled bit must have credence.

I may throw some OMC 2T and normal 2T at my lab - see what they come up with ... but won't be for a while - we are in move at moment and loads of work going through ...
 
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I have a 3.5 Merc on my tender and use Halfords 2 Stroke oil, never had any problems.

[/ QUOTE ] Yet.

Always buy any oil on specification - be it for a diesel engine, a petrol engine, or a water cooled two stroke or an air cooled 2 stroke. Brand is immaterial, though brandowners try to hide that fact.

The spec is usually hidden as an API number in small print (American Petroleum Institution - I think). Their web site produces wonderful lists of which specs supersede which others, and which are suitable equivalents . . .
 
Halfords sell oil for high temperature air cooled 2 stroke engines that 16 year olds buzz around on, as will the lawnmower / strimmer / chainsaw shop.

The good news is TCW-III is great for outboards, and Quicksilver (the stuff mercury / Mariner bring to market) is almost as good as OMC (Johnson / Evinrude).

It is designed for outboards which are over cooled, and is very low ash to prolong plug life, particularly if used at low speeds (by plug life I mean the duration between when clean-ups are required).

Use any old crap for the first concentrated tank full may lead to starting problems due to plug fouling, and unnecisarily coat the power head with excessive deposits.

If you got this far on the web, you could have a litre delivered to you tomorrow from one of the big mail order chandlers, ask the engine supplier to help, or have a drive to your local dealer:

http://www.walkeroutboards.co.uk/
 
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