Exhaust Leak

[DOCDRS]

Had a chance to check into my leak in the area of the port side exhaust outlet. I took off the flapper then took the screws out.....they were not very tight......then I loosened the internal clamps holding the exhaust hose onto the plastic thru hull fitting......when I went back out to the exhaust outlet it was about 1/2 inch out from the hull. the silicone does not adhere to the plastic well and was the source of the leak I believe.....i cleaned it up and re glued it using some polyurethane goop after acetone cleaning of both parts....... I removed the flapper and tightened the screws on the starboard side

Note , I probably would have never noticed this leak with out the dripless seal as my bilge is bone dry usually.

[maxpower220]

Had that happen in a boat, but I used JB Weld and never had another issue.

[squeeg333]

So it was leaking around where the exhaust hose meets the flapper - inside the boat? I think I might have a simlar issue if I remember right. I had sevral very minor leaks at the back of the boat last year. Drain plug, port ballast discharge pump, and I believe one or both of those exhaust hose/flapper connections. I don't really remember, so I'll have to water test it.
But Doug, what was the leak you were experiencing??

[DOCDRS]

So it was leaking around where the exhaust hose meets the flapper - inside the boat? I think I might have a simlar issue if I remember right. I had sevral very minor leaks at the back of the boat last year. Drain plug, port ballast discharge pump, and I believe one or both of those exhaust hose/flapper connections. I don't really remember, so I'll have to water test it.
But Doug, what was the leak you were experiencing??


The leak was between the plastic thru hull fitting and the boat. The silicon that they use to seal/adhere the fitting to the boat failed. I resealed it. It appeared to be some basic white silicone that acted only as a gasket type material between the fitting and the exterior of the boat. If I had of tightened the 6 screws it may have stopped the leak but I decided to reglue/seal it. My camera battery was dead so I have no pics....sorry

[squeeg333]

That makes sense Doug, no need for photos. I recall the screws you're talking about, and I'm sure they used the same type of sealant that they used on the rest of the thrue-hull parts. I might just tackle this and re-seal it prior to getting it in the water, just to be sure.

[squeeg333]

Doug, looks like I've got the same issue as you. Got the boat in the water finally this past weekend, and had a very minor leak from both the boat drain plug and at least one of the exhaust ports. I believe it's the same issue you've got. I figure I can tackle that one pretty easy. Silicone probably isn't the best thing to use betwee the hull and the exhaust port, so I'll need to try to find something a little sturdier.

The drain plug is going to be a bear though. I tried to remove the entire thing last year when I noticed the leak, and the housing wouldn't budge. I had hoped just putting pipe tape on the threads would cure the leak, but no dice. I am thinking now about either sealing from the inside around the end of the housing and the hull or re-sealing from the outside around the housing and the hull.

[DOCDRS]

I believe another component in the exhaust leak is a faulty tranny mount bushing. I'm going to shoot a vid of changing it this weekend and aligning the prop shaft.

[mnpracing]

I believe another component in the exhaust leak is a faulty tranny mount bushing. I'm going to shoot a vid of changing it this weekend and aligning the prop shaft.

How would the tranny mount affect the exhaust leak?

[squeeg333]

I think I may have found something interesting while trying to repair the leak that might be coming from the exhaust. I noticed that the thru-hull plastic exhaust port came off really easily, and none of the sealant was left stuck to the plastic. So, I saw what you did Doug, not much sealing.
Once I went to put it back on, I noticed that when I squirted the new sealer into each of the 6 screw holes, that it actually came out on the inside of the boat. So, what I'm thinking is that part of the issue could be that these holes have the potential to go all the way into the boat, and if the sealant degrades or anything at all around these screws - you'll have leaks. I also noticed small cracks where the holes had been drilled on the two screw holes closest to the bottom of the boat. I think one other place for water get in would be these small cracks. (These cracks were seen from the bore drilled into the fiberglass for the exhaust flapper housing, so they weren't exterior to the boat). My descriptions suck, I know this...

So, hopefully I injected enough sealer into the holes and around the flange to make the leaks (if that's where I'm getting them from) stop. We'll see tomorrow.

While I was back there, I unscrewed the screws holding the drain plug housing in, and injected some sealer in those holes as well. Maybe that will cure the leak that I'm seeing there.

[DOCDRS]

How would the tranny mount affect the exhaust leak?Basically the mount had a lip that trashed the inside of the rubber bushing and the front starboard corner of the engine lowered probably at least 1/4 of an inch. I just replaced the rubber mount, about 1 hour and a beer to raise and support the tranny mount, undo the lower nylock , remove the holding bolt , remove the rubber bushing, install new bushing, reinstall bolt and lower nylock and bringsto similar tolerances as port side. Then undo coupler bolts and fine tune the alignment.....I was within a 1/4 of a bolt turn to get less than .002. Oh, I also filed and smoothed the raised lip on the mount under the bushing so it does not happen again. I took pics and video and will post later in how to