Gimbal ring and transom plate for a merc/ bravo III

rasbury

since I have never seen a transom assembly out of a boat, I am searching on line for pictures of the components to understand better where my leak is coming from. From what I seen on line, the out side gimbal ring is really nothing more than that-I'm guessing there is some sort of outer seal on that and will look at my manual.

The inner transom plate is a little more confusing looking at the holes in the plate. From the top down, I see a pretty large rectangular hole that I recognize as where the steering arm goes into so I'm good there. That's about as much of that plate you can see with the plate in the boat with the motor. Next down I see what appear to be 3 holes- these are for what I assume from right to left as the speedometer, then the water tube from the foot. I'm not sure what the third hole on the very left would be for.

Below that I see a large rectangular hole which I thought would have been for the drive shaft from the out drive- below that there is a round hole which I guess is for the exhaust. If the rectangular hole is for the drive shaft, where in the transom asy. does the bearing actually mount? Below that the pictures I see they have 3 small holes kind of centered which I don't know what they do, perhaps part of the mounting to the gimbal ring...and then a hole off to the left for the shift cable to go through.....from what I see from my leak, water is coming in from around where the water tube comes in- or perhaps I have a cracked transom plate? The leak is much worse than when I started, I had a heck of a time getting the bearing out with a slide hammer....I hope that is not a case of I had a crack that was leaking before and now I really made it worse......that's why I'm looking for the relationship of where that bearing sits to the inner transom ring...

rasbury

https://www.ebay.com/i/311144857434?chn=ps is the picture I found...how about it @alswagg am I looking at the right one for 350 motor and bravo III, any comment on the holes? Most puzzled by the hole the bearing for the out drive area sits and then the exhaust is round? Is there another plate on the inside I'm not seeing?

davidbrooks

Ras i had both off my boat this summer....sigh and bought new transom assemblies to replace them with.  So unfortunately i am intimately familiar with them.  Inner and outer assembly basically sandwich the hull.  There a fairly decent amount of sealant that is put on the rings before they are then bolted in and torqued down with the excess being left to bulge out just a little.  Everything from the outer assembly feeds through some boot one way or another to the inside.  The bad news is that to replace the transom assembly you have to pull the motor and the transom assembly bolts can be **** to get out.  Prepare to spend some time with a torch heating them up and soaking them in break free.  One it is out though you can do it right.  And trust me it is a lot easier to wrestle with it on the garage floor vs the back of the boat.  I found a TA for about $1600 and that is complete and brand new.  There have been improvements over the years and one of the big one is the connection for the fresh water.  It basically collapsed on the older styles and is much more open now.  Water could be leaking around the plates... around the gimbal rings, shift boot..water intake.. really hard to tell without getting in there.

rasbury

thanks @davidbrooks and I don't know yet that this is my problem- I'm trying to understand how things come through there- I did my bearing, and all my bellows- I did not do the water pickup tube (should of) or mess with the trim wires ( that's what the other hole on the top was for!) or the speedometer- although the tubing on the inside was broken off. It appears to be leaking right around the area of these 3 holes- or perhaps the edge of the plate perhaps. I need to get back in the water and look but just trying to understand how things work. Also, in looking at the pictures of the inner transom plate, it does not seem to have a thick enough area to support the bearing but I suppose that is what it rests in, correct?

rasbury

and if you look at the picture, if that indeed is the same as mine, the round hole is on the bottom which would have to be the exhaust and the rectangular hole above it would be where the drive shaft would come through, where is the bearing sitting?

Cableguy Greg

The drive shaft goes thru the round hole in the center of the assembly. The bearing is mounted there. The exhaust goes thru the bottom of the assembly, the section on the ebay photo that looks like a trapezoid.

rasbury

Well that makes much more sense then, thanks cableguy greg  that area around the top edge of the bearing looks like it could be fragile- if your really knocking on a bearing to get it out I suppose you could break it? I think the leak is higher than that- either trim, speedometer  or water pickup tube - at least I know better what I'm feeling with my hands as you sure can't see it!

Cableguy Greg

The shift cable goes thru in the circle that is off to the side of the rectangle hole. If I am a betting man, which I am not, I would check the shift boot first.

rasbury

Thanks- I replaced that and when I briefly dunked the boat it is leaking somewhere lower than the shift pin but higher than the drive bellows...

Handymans342

Maybe a TA crack?

rasbury

I sure would like to rule that out....

Handymans342

Well the guys on here with TA cracks have had various volumes of leakage. 

rasbury

Yea.....im hoping for not...

rasbury

So, while I'm not yet back to the water but keep looking at that transom plate and I read through the archive and saw a post from Al...if something struck the drive it could shift that transom ring enough yo break the seal. It send my problems started after a coupler repair and I did connect with something underwater son time before the coupler failed. I look at the seal kit for the gimbal ring and try to make sense of where the seal actually seals. On the transom plate just above where the bearing sits there is a pretty large opening- what is that for? My leak is around the top of that or the 3 holes for trim, Speedo and the water tube. The transom would not be cut out to match that opening? Where does the seal do its thing in this area? Can wait until these holidays are over!