1989 Sailfish transom bracket leak

[BostonHack]

I'm getting water inside my bracket. I've been pumping it out when I notice listing toward the stern, but can't determine the source. Sitting for several days does not show any leakage. But only sometimes when I'm out - I'll come back with a full bracket? I'm thinking it must be getting in from between the glass and the bracket.

What is the procedure for determining the problem and the fix? Can I just caulk the seam between the bracket and the boat?

Thanks a bunch,

John

 

[seasick]

What do you mean by "But only sometimes when I'm out - I'll come back with a full bracket"
Are you saying that the bilge is filling up or is it something else.
Is this an I/O or an outboard app?

 

[BostonHack]

It's an outboard with a Gil bracket: http://www.corsaperf.com/gil_marine/pro ... ckets.html

It's a sealed unit for mounting the outboards. I can pump out most of the water, say about 1" left. Sitting in the water all week, I'll come back and there's still only 1". I've taken the boat out for a couple of hours and looked and will still have 1". Other times, I'll take it out and I'll have 10"... and then I repump to 1"... and have done this several times.

 

[BobP]

When you take the boat out of the water, open the top port and fill it with the garden hose to the very top, then wait to look for leaks outside. May be just a few drops once in a while so you have to look closely.

It is not likely the outside joint on the sides and bottom. It may be the top seam, lower motor bolts holes, zinc holes, drain plug hole, or the very cover you are opening on top. If none of these areas leak but it is another spot leaking may be galvanic corrosion pin hole damaged, if it doesn't leak may be the top seam on the top cover.

 

[BobP]

last sentence -

...may be the top seam or top cover(s).

 

[wilson]

if the bracket was painted with bottom paint it's probably got pin holes in it from galvanic corrosion. and or it's the lower engine mounting bolts. they would be hard to seal. i trailer so when i get home i remove the plugs and a cup or two always drains out. just a design flaw, they all do it.

 

[Grog]

It doens't sound good. The water can be from a leaking engine bolt but those usually always leak. It sounds like the transom is flexing causing the water leak or the bracket is really toast and has a crack. If you sealed the inspection covers I can't see 10" getting inside the bracket from splashing. Either way I'd pull the boat and check things.

 

[seasick]

Grog,
It could be that the bracket bolts are not snug and the whole unit is pulling away from the transom under load. Hopefully, the transom is sound.

 

[BostonHack]

Lot's of good suggestions... I was hoping it might be something I could investigate, but after listening to all the possibilities, I'm now thinking I'll ask the marina to check into it when I pull it.

My transom is good - I've had it checked professionally (although one of the bolts holding the bracket is overtightened). I did have it soda-blasted this spring and although there were small pits, it looked ok to me. I noticed however there was a bit of water left in from last season (I bought the boat this spring). I was worried that if it froze in the winter, it might have cracked the bracket. The brass drainplugs are also seized...

Anybody know someone with expertise with these brackets in the Wareham, MA area?

 

[Grog]

Grog,
It could be that the bracket bolts are not snug and the whole unit is pulling away from the transom under load. Hopefully, the transom is sound.

The problem is why the transom bolts aren't snug.

A little bit of water in the bottom isn't going to crack the bracket. If the ice/water has somewhere to go when it expands it'll be OK. You don't want brass drainplugs. Aluminum or even PVC but you don't want to introduce anything that will react with Aluminum.

Yank the bracket when the season is over and evaluate it. Minor pitting is to be expected but no areas that are thin. Blast it and paint/epoxy whatever just isolate the Aluminum from the salt water. If you want to go new, there are many options Aluminum or fiberglass, standard or floatation and the price varries.

The transom was given a clean bill of health but from your description, it's pointing towards the transom.

 

[choogenboom]

Last summer I discovered the bracket on my 228G was full to the top (ie above the water line!) with seawater. I should mention the boat is moored at my dock year around.

To diagnose the cause is not hard ... you can do this yourself.

1. Drain all the water.

2. Make up a spray bottle with soapy water - dish soap works well. Spray soapy water all around where the bracket mounts to the transom, the inspection plate, the engine mounting bolts - basically spray every spot you think might be the source of the leak.

3. Using a compressor, lightly pressurize the bracket through the drain plug hole. I used a 1/4" NPT coupling to adapt my compressor nozzle to the drain plug hole. Do not overpressurize!

4. Look for bubbles. Bubbles == leak.

I did this test and confirmed my leak was at the inspection plate. Some genius (not me - I never had the inspection plate off until this incident) removed the inspection plate (why I don't know as there is no reason to remove it) then overtightened the screws on the inspection plate. Half my screws holes were stripped out. The screws are backed with a nylon ring on the insde of the bracket which can't take much screw torque. Gil marine sells replacements. I washed out the inside of the bracket with fresh water, shop vac'ed it dry, then let it sit in the sun to make sure it was dry. I replaced the nylon backing ring, greased the o-ring liberally with marine grease, and then sealed it up. I then pressure tested again to confirm the repair and found no leaks.