102 oil mix

[Scho]

I have a 1960 102 seagull with an amal 2 jet carb. Can it be converted to 25:1 at all?

[woodbutchergraham]

Good question, to which I have to ask why would you want too. There is more than one reason I could think of such as the environmental issues. But the benefits of this heavy fuel have on bearings and sealing crank casings surly out way the saving on two stroke. As all my Seagulls run on 10;1 mix I use Bio two stroke ( hay that’s just my opinion)

[Keith.P]

Is that an answer
Some people like to run a seagull on as less oil as the motor will allow, for environmental as much as the cost of the stuff.
I also run 10:1, but only because I have to, if I could convert to 25:1 I would.

Answer : No they can not be converted.

[RickUK]

Scho - you can physically convert yur engine to run on 25:1 by changing jets, but it is not a suitable conversion because of the bearing surfaces (apparently).
I use a 15:1 mix with the modern TCW3 oils, and generally the synthetic types - I am sure these oils are fine at these ratios, and the likelihood is that we all use our engines very lightly over the course of a year.

[atoyot]

I'd have to agree with the others, that the benefit to these engines in using a generous oil mix outweigh any other consideration, if you want your engine to last. Being as I work for a state environmental regulatory agency, I should be the first one to say otherwise, though there are other routes one can take to protect the environment.

The first and most obvious is, stop using two-stroke engines, period.

Failing that, there are biodegradable products out there that break down naturally, in time. In the states, the retailer West Marine markets a synthetic 2-stroke oil based on rapeseed oil rather than on petroleum. It costs twice as much as the petro variety but for as little as I use an engine it's worth the cost.

Now down from my soap box, I've noticed that my Seagulls (2 of them) seem to start easier with 16:1 or better (closer to 10:1), than they have when experimenting with 25:1. It may be only perception though the theory is that there's better compression with the "right" amount of oil being in use.