Outboard Well & Gas Fumes

[Bogle]

My 8 hp, two-str oke OMC outboard runs in the well of my commander. After running a while we get gasoline fumes below.

I don't detect any leaks from the line or engine, but it is a two-stroke... Even if it were leaking gas into the well, how would they be getting below?

I have epoxy sealed the worn areas in the well, and all the joints between the sole, bulkhead, hull and well. Also I sealed with epoxy the aft wall of the well where the upper exhaust sprays.

What should my next move should be? Replace my fuel line, Remove the sole of the well to rebuild/seal, Barrier coat my hull (maybe the gasoline slick on the water is soaking through)?

(BTW, with the top closed and cockpit hatch open it does not suffocate when run at high speeds, but that's another thread.)

Regards,
David
commander #92, la saladita

[Mike Goodwin]

Try plugging the lazarette drain hole and pouring in 5 or 10 gals of water to see where it goes .
If any gets to the bilge , then you know there is a low hole in the bulkhead .
You might add food coloring to the water to make it more visable .

[Bogle]

Mike,

Thanks for the note. That drain hole did cross my mind on one sail this season, and d*mned if I did not forget about it. There are the culprits (the drain hole and my aging mind.)

I cleaned out a bunch of silicone somebody had put in there, presumably trying to patch it up. My bilge is generally pretty dry, but it does not take more than a few drops of gas to make a stink.

Thanks again. In the spring I will epoxy in a new tube or something.

[Bill]

Although we did not get fumes below, we found the foam under the sole in the lazarette soaked with water and fuel. Analysis indicates that water and spilled fuel was entering the area, in part, because the fiberglass "seal" was damaged between the lazarette sole and where it meets the inside of the transom. The crack was totally invisible to my eyes! We removed and replaced it all. Now, we just have to keep backing power boats from running into us when we're in our slip

[John]

On Valhalla, Commander # 287, we have not seen that cracking although we did shoot ourselves in the bilge, so to speak. There is an access hole high on the lazarette partition on the starboard side that is for the lines from the engine to the battery. When we are close hauled in high winds, that hole can be below the waterline, we discovered. It really is amazing how much water a 1" hole can let in! I am considering cutting some hard foam to make a plug because of the lazarette flooding at speds over 5 kn.

Our current engine is a 87 Johnson 9.9, and we get fumes from the bypass outlet in the top of the shaft. We can't run with the hatch cover down without the motor suffocating. Has anybody changed the hatch venting and been successful?

[Bogle]

John,

See the recent thread entitled Outboard Exhaust.