Boat engine smoking

[toddspolaris]

Thought I might get better response here, but anyway my parents boat is a 1987 four winns 190 Horizon with a 350 cc motor in it. I'm an atv mechanic and also have done all the maintanance to this boat, but what it does is puzzling me. You start the motor and idle out into the lake and its ok. Then go skiing or what ever so everything gets hot and then come down to an idle and blue smoke comes out of the water.I have checked the oil level and its right on the full level, I've pulled all 8 spark plugs hoping to find an oily plug but they all look like they'r burning perfectly, they actually idled quite along time before they pulled the boat out of the lake, so that why I was looking at the spark plugs for help. Any other ideas out there

 

[pistons]

Maybe valve seals are getting wore. When the oil gets hot and the seals get soft some oil gets by. When you go from full throttle to idle,the engine will pull more vacuum and sucks oil past the seals. You can really see it when someone passes you in a car and lets off the gas when they get around you, the blue smoke comes out the tail pipe.

 

[skidoolis]

Like pistons said valve seal are worn out.easy fix if you have a air compressor.with fitting fill cylinder up remove rocker and seal install new seal mind you keep air going into cylinder.(or you will drop valve in head) another trick use some rope feed through spark plug hole turn engine over to put pressure on valve and do the same.install rocker and adjust use these to keep oil mess down while adjusting valve lash good luck i just did a broken valve spring in my chevy truck

 

[booondocker]

If you are loosing so little oil that you can't see the level going down, then leave it alone. The little it uses won't be an issue for a long time. Just watch the level to be sure it doesn't become a bigger issue down the road.

Sort of like fixing something that isn't really broke.

 

[ezra]

try nicorette

 

[dondoo]

Maybe this boat is to small to smoke and you need a bigger boat!

What did the big chimney say to the little chimney?------ your too small to smoke... LOL

 

[andoverboyz]

I agree with Boondocker, just keep an eye on the oil level changing.

Ironically I'll be running a 84' 190 horizon with a 350 today, I'll see if it's doing the same thing. Remember they're over 20 years old ,the one I own has not had any major motor problems (my family has owned it since it was new), just done the preventive maint. Still runs around 57 on the speedo, it can't beat our Baja but it actually handles better, helluva boat for what it is.