Transom Leaking

[MoonRiver]

After launching my 1994 2700SCR a week ago I have water in my bilge.

The water appears to be coming in from the transom area (its hard to see on these boats) but I can see water trickling across the transom plate just below the shaft on the strbd side. I could not see where the water was entering the boat. I pulled the boat out and took it to my marine buddy, he removed the outdrive because we both suspected U-Joint bellows or shift bellows. Turns out they where both just fine (bone dry inside UJ bellow).

Mechanic suspects it my be coming in around the swivel pin seals. I have done some research and inspected this area (out of the water) and it does seem suspect, the boat is 24 years old. So I am going to float it tomorrow to see if I can pinpoint the where the water is entering the hull. If it is the seals on the swivel pin this usually requires an engine pull, but I have read/ heard about a company who makes a kit to gain access to the nut from the external side of the transom.

Has anyone heard or used this kit?
How hard is it?
Any draw backs? Pro's and Con's

[mmwjr]

When you say entering just below the shaft do mean drive shaft?

Mercruiser makes a kit to replace the swivel shaft and seals without removing the engine as does JR Marine. The JR Marine kit allows for better access to do this but requires cutting away a large piece of material just above the swivel shaft. The kit comes with a plate that gets screwed and sealant to cover access hole. I have read of many folks using the JR Marine kit and none had issues with it. I attached a link for instructions.

Note the stock swivel shaft is steel which rusts over time which is worse for boats kept in the water however Mercruiser does make a SS replacement you just need to ask for it.

Instructions

[MoonRiver]

When I say entering I meant was pooling on the flange just below the drive shaft. But I don’t believe the water is entering the boat at that point cuz the UJ / drive shaft bellows are bone dry.
I have been reading about the JR Marine kit. After my water test today I will be able to make a go - no go decision. The JR kit looks farly straight forward, but that means nothing until the job is done and you get to say I saved myself $3000-$5000 bucks.
I’ll try to document this project for all of us to see

[shrew]

What kind of outdrive is it?

[MoonRiver]

Sorry, It’s a Bravo II I thought I stated that earlier. I’m trying to pictures posted

[MoonRiver]

Well its official, while launching the boat last weekend I slowly backed the boat in checking for leaks every couple of inches. No water until the top of the transom housing (bell housing) entered the water. The leak is a slow trickle and it is definitely coming in around the swivel shaft. So it looks like I will be performing transom surgery this fall.

I replaced my float switch and tested the bilge pumps, which are newer. The auto switch only came on 2-3 times after an entire day on the water. So I will monitor daily and hope for a long summer on the lake.

[mmwjr]

Do you have shore power to keep the batteries topped off incase you are away for an extended time?

[Gugi47]

Originally Posted by MoonRiver

Well its official, while launching the boat last weekend I slowly backed the boat in checking for leaks every couple of inches. No water until the top of the transom housing (bell housing) entered the water. The leak is a slow trickle and it is definitely coming in around the swivel shaft. So it looks like I will be performing transom surgery this fall.

I replaced my float switch and tested the bilge pumps, which are newer. The auto switch only came on 2-3 times after an entire day on the water. So I will monitor daily and hope for a long summer on the lake.

If you get water in around the bellhousing, can be the O ring or you have soft spat on the boat. If is the first one is a easy job the 2nd will be expensive, the engine have to come out. I hope is not the case. If is the O ring. Before you instal it back clean everything very good.

[MoonRiver]

Update to the post,
I brought the boat home from winter storage and began dissembling the outdrive, bellhousing, and gimble ring. Everything came apart unusually easy, both to my surprise and a wee bit of concern. My drive bellows and shift bellows are both in great shape so left them connected to the transom plate. It was a little difficult to remove the swivel shaft bushing but it finally gave up and got out of my way. I have not been able to remove the smaller upper bushing. I have used flat bottom slide hammer tool but it will not budge. So I have decided to leave it in place. It really only guides the swivel shaft about the water line on the dry side of the shaft.
As always one project lends its self to others. I will be replacing my trim switches, while Im in this deep. My gimble ring and steering arm are in great shape the only damaged part I found was the spring wire rubber seal that sets on the swivel shaft.
Drilling the first hole in the transom housing was a bit scary but 35 holes later I had nice access port to attach the the swivel shaft retention bolt and upper nut. The wrenches that CP Performance sent me needed to be modified further (I hope they dont mind too much).
I have everything laid out, painted, greased and locktie ready for re-assembly. An of course my trusty torque wrench.

[mmwjr]

Thanks for the update, any pictures of the project?

[MoonRiver]

I’ve got a few pictures of the old vs new parts, nice template hole in my transom, gimble ring, steering arm, and bell housing.


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[mmwjr]

That’s the nicest cutout I’ve seen for this job.

[MoonRiver]

After reading quite a few stories about doing this mod I purchase a 12 pack of 3/32" high strength bits and still broke 6!!! It my only be aluminum but its thick. Im pretty happy with the work so far. It super nice having the boat backed up to my garage bay.

[MoonRiver]

Got everything back together. Getting the new trim switches to line-up and register correctly was a PITA. But patience and a couple of beers always seems to help. Time to seal everything up and start her up tomorrow. Should be in the water for the season next weekend.

[mmwjr]

The senders have a home position designated by a slightly bigger spline in one position.

[MoonRiver]

Yep your absolutely correct and I eventually figured that out.
Nice and shiny.


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[mmwjr]

Looking good.

[MoonRiver]

Update:
Launched the boat past Friday all dry on first inspection. But, a small drip appeared in on the transom assembly within an inch of the old swivel shaft leak. Ya my heart sunk and a bunch of really bad words echoed out of the engine bay. After a some deep breathing and calming I found the a leaking speedo hose. Turned out to be a snip and new zip-tie fixed the issue and off we went to our summer slip.

[mmwjr]

Now relax and enjoy the season.

[broncostu]

what is the modification for?