Exhaust fumes are killing me...

[jheron]

Well I am taking the plunge and getting married in May, and next will come the kids :'(
So what does this have to do with exhaust fumes you ask??
Well our 2003 17' Lowe Fish n ski with a 1976 115HP tower of power (old smoky) on the back has a problem with sucking exhaust fumes back into the boat. This was never really a huge concern for me in the past but now that I might be hauling a pregnant lady around I wonder if there is anything I can do to mitigate the problem?
I believe that the problem is caused by a low pressure area at the transom and behind the windshield. When going into the wind with the top up you can see the blue smoke come up over the transom, across the floor and dissipate rite behind the windshield where we sit :% Opening the windshield gives us relief but is very unpractical when fighting big water into the wind... unless your a duck! (we boat on lake Huron)
So I am going to buy a good marine CO detector, but wonder if there is anything else I can do to stop the back draft? Maybe an airfoil on the bimini or something??
Any and all suggestions are greatly appreciated....

Warm regards,
Jon

 

[Bondo]

Re: Exhaust fumes are killing me...

Any and all suggestions are appreciated....

A Much Bigger Boat,............ With an I/O..........

 

[scoutabout]

Re: Exhaust fumes are killing me...

Funny, my old two-strokes always gagged me when going with the wind at idle. Just, me and the missus drifting in a blue fog together...d

You see those guys who screw plexiglas barriers on either side of their outboards for trolling backwards. Something like that but higher might be just enough so that by the time the blue cloud has climbed the height of it the wind over the top of the bimini might carry it backwards.

Wouldn't be the prettiest setup you ever saw, however.

You didn't mention if you had side curtains up during these rides. If so, perhaps a happy medium would be to take them out but keep the windshield closed. That might give you enough draft sucked in from the sides to dissapate the fumes.

 

[Chris1956]

Re: Exhaust fumes are killing me...

Jhuron, It is likely the top which is creating the vacuum and sucking the fumes in. One of my hatchback cars did the same when I had the lumber sticking out the back.d

You can run a synthetic or synthetic-blend two cycle oil in that motor. It will be less smoky and stinky that way. I do not think you have a CO issue, but I think it a good idea to find out for sure.

The only other thing I can think of is some sort of plastic sheets (try plywood for a test) on both sides of the OB, sticking out over the water. This might change the airflow a bit.

 

[tommays]

Re: Exhaust fumes are killing me...

Well this a huge problem in the boat industry

There are many NEW big boats that are to dangerous to even sit in the seating area with the boat underway even at planeing speeds :devil:



Tommays

 

[jheron]

Re: Exhaust fumes are killing me...

Thanks for your insight guys!
To answer some of your questions:
The fumes are far worse with sides on but even with them off I get a headache, but only when going into the wind. I am sure that it is CO mixed in with the smoke, how could it not be? Adding synthetics and other snake oils will not affect CO just the smell of the exhaust... It will still kill you...
Its strange that I even have the problem considering that there is an opening under the windshield for the walkthrough about 2'X16". You would think this would eliminate the low pressure area but it doesn't?? Maybe because the opening is below the gunnel's?
I sure wish I had a wind tunnel and some smoke generators in my back yard for testing :devil:
Thanks again for all the input...
sincerely Jon