water leak diagnosis

I have made an assumption that I have a water leak due to a driveshaft bellows, but before I get started on a major (for me) undertaking, I would like to provide an observation that might help diagnose where I am taking on water.

I recently resealed my upper unit due to a bad seal. When I put the drive back on, I had a binding in my shift cable, so I decided that I got something wrong on the installation and again removed my outdrive. I did not replace the gasket/o-rings (to bell housing) when I reinstalled as it had only been on a day or so (Don S in another thread scolded someone for not replacing them each time the drive was removed).

When I launched my boat, I immediately took on clear lake water. I figured I didn't put the hull plug in tight enough, so I dove down and put a different plug in, nice and secure. I fired up my fine machine and took her out for my second "sea-trial" of the season. When underway, my bilge was taking on "dirty water" as if mixed with things mechanical. I put the boat in her slip and went home, thinking about what was going on. After dinner, it was killing me with worry, so I went back up to the lake to see if the leak was any worse. After a 4 hour period, I had about 2 gallons of clear lake water in the bilge, and decided that I would pull her out in the morning.

Sunday morning, longing for a continuation of my sea trial, after pumping out more clear lake water, I motored around the lake for about 20 minutes, checking out my newly installed impeller, and a few other maintenance items of my project boat. Again, I noticed "dirty water" coming out of the bilge pump (not the nice clear water if sitting without engine running).

While I think this is a driveshaft bellows, would the changed bilge water indicate a different problem? Clear when engine off and moored, dirty when under load/under way?

PS, I ran some 2 cycle gasoline in my 350 Mag with a outboard tank while conducting some maintenance (my under floor tank was contaminated at the time), so the internal cavities of my outdrive had some black exhaust film on them, which I thought maybe what was turning the water dirty.

Jake

Re: water leak diagnosis

One of my non-mechanic boat owner colleagues suggested that the dirty water was a result of exhaust gases mixed with the water. Can this get into the bilge via the gimbal bearing? If so, would that indicate that the bell housing gasket is at fault here?

Re: water leak diagnosis

Pull the drive and check for water in the bellows, it's just that easy. Also check the gear lube in the drive. When water gets in the bellows, it gets in the input shaft seal of the drive. It wasn't designed to keep water out, only gear lube in. When water gets in, the drive is overfilled, when that happens the water and oil mix, then it expands from the heat and gets pushed back into the bellows. You are also washing the grease out of the gimbal bearing and the bearing gets rusty (The brown color) mixed with the grease and gear lube and you have a mess.
All to save 6 bucks on new gaskets...................

Re: water leak diagnosis

Don S is 100% right, pull the outdrive back off and check the outdrive oil, and bellows, it will cost you a small fortune latter if that is the problem, and it goes unchecked

Re: water leak diagnosis

Got it, guys, thanks. I will pull the drive, for sure, and would not just ignore this and hope it just goes away (I hate being a "cadet"). I suppose the question remains: When I pull the drive, and there is water in the bellows, that doesn't necessarily mean the bellows itself is bad, does it? To answer my own question, if it is the used gasket at fault, I would probably see some sign of water intrusion on the mating surfaces. Perhaps I will pull the drive and replace the gaskets and then float test again? Is there any sealant I should use on the gasket (such as perfect seal)? The gasket I purchased before had a red line on one side of the gasket.

Thanks again for your advise....this is a great forum and I have learned a ton.

Re: water leak diagnosis

I would reccomend useing a sealer, and after you replace the gaskets, and o-rings, just look really good at the bellows Rips-tears-holes-cracks, make sure when you have the outdrive off, you grease up the gimbal bearing, ujoints, and shift dog, you can do all of this right, just to find out that the bellows is leaking, so look reallly good

Re: water leak diagnosis

OK, Pulled the drive some water came out when I pulled the upper away from the bell housing. Upon examination of the u-joint bellows, there was some what looked like uncontaminated gear oil in the bellows (maybe 6-8 ounces), no sign of water in the bellows, and the gear oil in the outdrive seemed uncontaminated (not milky or streaky as checked from the fill plug). I can't "feel any cracks or holes in the bellow from the inside out.......

Now I am starting to wonder if water is entering the boat through the gimbal bearing after all.

Could it be coming in through the shift shaft bellows?

Any and all ideas would be most appreciated.

Re: water leak diagnosis

when you installed the drive did you glue the thick rubber ring in place? was it dislodged when you removed the drive or still in the housing?
shift boot is another possability

Re: water leak diagnosis

I did not glue it in place. When I pulled the drive, the ring came out halfway with the drive so it is hard to tell if this was somehow the culprit. I am going to examine it and see if it looks disfigured any, as if it were pinched or something.

Re: water leak diagnosis

OK, I examined this thing pretty good again. No water in the bellows. Ring looked normal and not deformed from a pinch during installation. Water passage o-ring looked good and remained in detente. I did observe a rubber gasket or bushing on the upper shift shaft between the exhaust port and the driveshaft port.

If this bushing is damaged, would water leak in through there? It would support the clean water entry while moored and dirty water (from the burnt oil film on the exhaust port (running two cycle fuel) when engine running/underway.

Any thoughts?