Reseal Exhaust at Transom

[zsuprausa]

Can anyone give some insight on resealing the exhaust exits. My 91 Marauder is taking on a little more water than normal and I am guessing it is through the exhaust. When the bilge pumps the water is fairly warm which is why I think it is coming in near the exhaust. Motor is dry and I did not observe any leaks from any of the hoses. Normal drips from the prop shaft packing nut. I have also observed the where the rudder comes up and it appears to be dry when sitting still in the water. The boat does not have supertraps just the rubber flappers hose clamped to the exits. I don't know if the exhaust is a solid pipe all the way back since there appears to be a rod sticking through each exhaust about 4 to 6 inches back from the transom. Are the screws through the transom just lagged in or is there nuts on the other side? Is pulling the flanges and remounting them fairly straight forward? I don't want to pull it apart and get myself in beyond what I have time for right now.

Thanks

[Jetlink]

Can you take a picture of your outlets? The way you describe it with the bolt running in the middle leads me to believe that there were once trapps installed on your boat.

[zsuprausa]

I have attached a few pics. Sorry for the quality. I was hanging upside down from the swim platform for the internal shot since my boat is sitting on my lift. I am the second owner and this is the 4th season I have had it. According to the original owner he said the boat was all original and nothing in the paperwork or original owners manual or Supra folder mentions SuperTraps. The line drawings in the owners manual show the flappers.

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[Jetlink]

No sweat, I would think pulling the flappers and flange off and dealing everything up again should take care of your problem if the exhaust is the source for your leak.

[zsuprausa]

Are the flange screws just lagged in? No nuts on the back. Any sealant recommended over others? I am also assuming that the exhaust pipe is one piece back to the rubber hose off the manifolds. Thanks in advance.

[wotan2525]

No, the rubber hoses just push fit into the exahaust flanges. If you pull off the flappers and then the thru-hull flanges, you can easily add some black RTV or 3M 5200 to the surface. Might be tricky to do while it's on a lift (I'd think it would be impossible.... unless you could get a ladder or something under it.)

Use a razor blade and some acetone solvent to clean off the old sealant. Be careful to not strip the screws as they go back in.... they are just self tapping, no nuts or anything on the back side.

You could also fill the existing holes with marine epoxy (if they seem loose.) Then redrill once the epoxy cures and reinstall the flanges and flappers.

[Jetlink]

What I did was to fill the screw holes with some sealant, thread the screw, then add a bead of sealant around the threads up near the head of the screw, then I ran the screw all the way flush with the transom again. Very effective at sealing it as my bilge is dry pretty much the entire time my boat is in the water.

[zsuprausa]

Thanks for the info. Going to put it on the trailer and try to fix it next week. A couple of other questions if you happen to know the answer:
- Is the pipe coming out the transom one piece all the back to the engine compartment? I am hoping its one piece and there isnt a coupling behind the transom under the gas tank.

- what is that rod in the picture sticking through the middle of the exhaust pipe? Its in both exhausts.:

[Jetlink]

The pipe should be a solid piece from the thru-hull all the way forward until it angles up from below the floor. The rod sticking out is what my Supertrapps used to be attached to. I had to cut the bolt down the length when I eliminated them as the bolt stuck out beyond the transom.