"Clams Canino" wrote in message
news:SIDEb.429634$ao4.1362098@attbi_s51...
If it's about air quality, then DFI would have to be exempted.

Personally, I don't think the aggregate number of 2 stroke outboards is
sufficiant to make a significant contribution to air pollution. While I'd
agree they are a lot dirtier than comparable 4 cycles, there just aren't
enough of them running to impact anything real.

-W

Most people are under the impression that a 4-stroke is cleaner, but a DFI,
such as a late model Evinrude, has fewer total emissions than a late model
EFI 4-stroke. The great thing about DFI is that its emission output stays
fairly steady throughout the life of the motor. On the other hand, a
4-stroke gets dirtier (increased hydrocarbon emissions) as it wears (about
350-400 hours) and oil starts getting by the rings and the valve guides. It
doesn't even have to "smoke" to drastically increase its emissions.

Bill Grannis
service manager