[Dersu Uzala]

I have a 1968 Evinrude 18 hp fastwin. The motor starts and runs well. The problem is that it runs "dirty," leaving a significant residue of gas on the surface of the water. At trolling speeds there is a constant rainbow on the surface of the water near the transom on both sides of the motor. When I kill the motor I get a rainbow area of gas about five feet in diameter. What could cause this and how can I fix it?

[coolguy147]

its normal and y the epa hates them

[samo_ott]

It probably is normal. 2 strokes do pollute more than 4 strokes. Are you mixing it 50:1? What you can try is full synthetic tcw-3 oil which is biodegradable also. It will smoke less and produce less 'sheen'. I get my Pennzoil synthetic tcw-3 at Wal Mart.