470 water leak, inside transom, on muffs

[dccordell]

Finally done with wiring and other stuff, so was testing out everything and fired up the motor. Fired right up, sounded good. After a couple minutes I noticed a small amount of water gathering around the inside transom assembly just beneath the gimbal bearing and where the yoke passes through the bearing into the inside of the boat. I'll get a picture of this tomorrow if needed...

Since this is just below the water hose tube, I felt around the end of the hose and it was dry, so the water isn't coming from the hose.

After running about 10 minutes, the water had accumulated enough to have dripped down into the bilge and started to drain forward (because I had the bow down at the time).

This was all done while running on muffs... the water was definitely not coolant from the closed cooling system. It didn't feel warm, just plain hose water from what I could tell. I didn't notice any oil mixed in it either.

Any ideas of what this could be? I'll probably pull the drive off tomorrow to check for water inside the u-joint bellows, but I read on another thread that while running on muffs, it's impossible for water to get into the u-joint bellows.

Maybe I missed an o-ring on the outdrive when I put it back together several months ago? I replaced the impeller... I'm going to recheck all of this when I get it apart.

Thanks for any info yall...

 

[Bt Doctur]

Re: 470 water leak, inside transom, on muffs

if you forgot the water passage O ring and damaged the big rubber ring , it can get into the gimbal bearing area

 

[dccordell]

Re: 470 water leak, inside transom, on muffs

I'm sure I didn't forget the water passage o-ring, I remember putting just a dab of o-ring lube on it to make it stick in position. Now by big rubber ring, you mean the real big one that is sorta flat (not round like an o-ring), that goes inside the bellhousing just before the outdrive? I'm sure that one went on too...

Hmm... guess I will see what the bellows looks like tomorrow, maybe that will point in the right direction. I'll let yall know!

 

[dccordell]

Re: 470 water leak, inside transom, on muffs

Ok so I got the drive off this morning. When I broke the seal between the drive and the bell housing, water poured out! Got the drive all the way off and there was water pooled up in the u-joint bellows, mixed with the gimbal bearing grease of course. The u-joint and pretty much everything inside there was wet and greasy (from the bearing grease mixing with water and slinging everywhere). I dried up all of the water and sprayed everything with pb blaster and greased the u-joints.. it hadn't rusted yet so trying to prevent that from happening.

The o-ring and big rubber seal were both in place and they look fine, no damage, as well as the drive/bell housing gasket. I'm stumped as to how the water got into the bellows to being with...

For what it's worth, I hooked the muffs up to the drive with it laying on the ground and turned on the water... none came out anywhere else but at the water hose outlet, but I know this probably doesn't mean anything at all.

Then I hooked the hose into the bell housing at the water inlet and cranked up the water... it didn't seem to be coming out of anywhere unusual, definitely none in the bearing or bellows.

Any ideas? Could it be something internal in the drive, and coming out around the u-joint shaft (for lack of the proper term)?

I checked the drive oil, it didn't appear to be any higher than before I ran the motor, and there wasn't any water on the top, idk about the bottom, I didn't drain it.

 

[stonyloam]

Re: 470 water leak, inside transom, on muffs

Have to look at what is possible and what is not, eliminate the impossible and what you have left however unlikely is it. On muffs it is impossible to get water in bellows from external source. Must be internal. Water on both sides of gasket and seal, must be coming from the outdrive side. The only way that I can see that happening is water leaking past the O ring and the gasket up into bellhousing past the seal into the bellows. The only other water in the outdrive is mixed with the exhaust gasses on the way out, and would be hot, and would not leak up into the bellows unless the exhaust was completely blocked. I think a impeller pump leak would just blow out the exhaust right? It sounds like for some reason the outdrive was not fully seated against the bellhousing and there was a gap around the O ring and gasket, and there would have also been a gap between the end of the outdrive and the large round rubber gasket. Maybe a piece of the old gasket was stuck on one of the mating surfaces. Try cleaning everything really well and putting it back together with a new gasket set. Just speculating. Good luck.

 

[Bt Doctur]

Re: 470 water leak, inside transom, on muffs

http://www.boatfix.com/merc/Servmanl/6/6A2R3.PDF
2A-15 this link

 

[dccordell]

Re: 470 water leak, inside transom, on muffs

The illustrations in that pdf sure look a lot better than the ones in my manual, Bt.. thanks for that link. That is exactly the process I've gone through putting the drive back on, so I'm sure I got it all in right.

Today I got a new seal kit from the merc shop and made sure everything was good and clean on the drive before putting it all back together. The only thing I found was a teeny little bit of the old big rubber seal, so I cleaned that off real good. The parts in the new kit looked identical to the parts I already had on there, except for the drive to bellhousing gasket had an orange lip around the edge of the seal on both sides, but my old gasket didn't. I dunno if that mattered...

So got it all put back on, fired her up and let it run about 15 minutes... no leaks! Can't say if I fixed the problem or not yet, but I will probably pull the drive and see if the bellows is full of water again or not... hopefully not! Shame those things aren't see-through! Hah..

I pumped the gimbal bearing a few more shots of marine grease while it was running, hoping no water is left. Guess we'll see... no rattling or rough noises coming from it yet.

Thanks for all the help yall! One more obstacle down...

 

[stonyloam]

Re: 470 water leak, inside transom, on muffs

I will probably pull the drive and see if the bellows is full of water again or not... hopefully not! Shame those things aren't see-through! Hah..

Let sleeping dogs lie