The exhaust ports are there to allow for a smooth idle. Allows for exhaust
to escape without all the backpressure of the water at idle.

As for the smoke, should not be excessive. You don't have oil in the gas
also I hope. Verify your plugs are clean and new and burning properly.
Other than that, there is no adjustment on the oil injection.

Tony

"MrDiesel" wrote in message
. com...
This is my first Johnson outboard (had merc's before). It is a '90 model
70
HP installed on a '88 tracker. The motor is oil injected and seems to
smoke
excessively at idle. At cruise and WOT the smoke is not noticeable. It
seems to me that at idle the are exhaust ports just below the motor that
are
out of the water and letting the smoke free into the air instead of in the
water. Is this common and normal? Are those really exhaust ports?