Bypass cover or crankcase gasket? Johnson gt150

[Odawg753]

hey guys first time poster after getting plenty of info from this site in years past I have a quick question. Boat has been sneezing at idle. Rebuilt carbs etc. and noticed small bubbles coming out of bottom cylinder on starboard side. Can't tell if it's crankcase or bypass cover leaking. Here is a video of it. It's leading me to believe it's the bypass cover because you can see the bubbles shooting towards the crankcase. This is the video: https://youtu.be/BCwRyU40k-I

 

[boobie]

From your video it looks like the cover gasket. But I may be wrong.

 

[emdsapmgr]

That's a good question. The two crankcase halves meet right next to the bypass cover on the starboard side. They are absolutely right on top of each other at that point. Easiest thing to do is remove the bypass cover and put a new gasket on it. If it's still leaking after the re-start, likely it's the crankcase halves.

 

[Odawg753]

Alright guys I changed the bypass cover gasket used permatex gasket sealer and it fixed it for about ten minutes. Idk why it would be leaking. Maybe it's warped?? Should I used two gaskets? Or should I used the liquid gasket stuff?? Any suggestions would be great. Finally got this thing running great n just need to fix this leak

 

[emdsapmgr]

I also use the Permatex type sealer. The creamy caramel colored sealer in the small can with a brush under the cap. These covers don't tend to warp-one gasket should be all you need. Any chance the cover has a hole in it from casting porosity? Some Marine Tex would fix that.