Smokes at start up

[Pilotnut]

I have twin 2007 Suzuki DF175s. Over the past two seasons, I've noticed a small amount of smoke (not steam) coming out of the exhaust from the motor upon start-up. This only occurs after the motor has been laid up for a period of time (a month or two).

The motor doesn't smoke at all during the rest of the season, nor does it consume an unusual amount of oil.

What do you think?

Thanks

[Harper]

Could be caused by one of the things you mention. That compression is a little low (specs call for 156-242), and the maximum difference between the highest and lowest cylinders should be only 14 PSI. A cylinder leak-down test might reveal something more.

[upshootie]

My DF250 was doing the same.... There wasn't anything wrong with the motor it was the way I was storing it. I had always stored motor with trim and tilt all the way down or tucked under, negative trim... to protect tilt and trim rods from air and getting rusty. But a four stroke needs to be stored with positive trim or trimmed up. Before you spend a bunch of money read this....

Four Stroke Outboard Smoking During Initial Start Up? | Fairwinds Marina

[artdf175]

I would also have your valves clearances checked
have you followed maintenance schedule outlined in the service manual?

As Harper mentioned those compression figures are a bit low
I have a DF175 2006 I acquired in the fall of '07
the engine had 25 hours on meter at the time
It was using oil from the start..it was not noticeable..
it now has 600 hours
this spring I finally bit the bullet and had it rebuilt
a year ago in checking valve clearances all were out of spec and tight, and intake for #2 were negative.
I suspect the person who I got the boat/motor did not break engine in correctly, if at all.

After what I went through, from what you describe, I would first check valves and then suggest running something like "ring free" through the engine and or a good fuel additive that may help clean out carbon deposits..

Art.........

[Muskykris]

My DF250 was doing the same.... There wasn't anything wrong with the motor it was the way I was storing it. I had always stored motor with trim and tilt all the way down or tucked under, negative trim... to protect tilt and trim rods from air and getting rusty. But a four stroke needs to be stored with positive trim or trimmed up. Before you spend a bunch of money read this....

Four Stroke Outboard Smoking During Initial Start Up? | Fairwinds Marina

Great advise
My old engine puffed oil on start up once in a while, got a 19’ df140 and decided to look into it and found this post.... hasn’t smoked since.

musky