Water coming in boat

[Shep111]

Hi all, need some help here. I have an 89 merc alpha1 I/O. Last fall I noticed my auto bilge pump running more frequently as it sat at my pier. While in the boat I looked & looked and couldn't find the leak. I decided because it wasn't too bad, I would wait till spring & look more closely. Well, it's spring & I came up with this idea, if water is coming in & filling the bilge compartment while in the water, then with it on the trailer, plug in & I fill it with water, it should leak out. Well, I figured once the water was at the right level it would most certainly be coming out from one of the bellows, even thou last year they looked new. To my surprise, after a short time, the water began to spill out, right at the bottom, out the two holes where the water is exhausted from the engine under normal running. I keep telling myself, if water can run out these holes with the bilge compartment full, while on the trailer, then it must beable to run in the boat while it's sitting in the water, but from where??? Any and all idea's are very appreciated. Thanx............Shep

 

[Don S]

Re: Water coming in boat

Probably where the exhaust tube or Y bolts to the transom shield. There is a seal ring that goes between the two. Requires an engine removal to replace.

 

[Shep111]

Re: Water coming in boat

Thanx Don.......not exactly want a person wants to hear, but over the years of taking this thing apart and back together, ya just get used to it.....lol.
I had supected the exhaust elbow, which houses the shutters......but logic kept telling me, the shutters only work one direction, out, so how could that happen, unless they were somehow damaged, over heated etc. At any rate, you probably still have to pull the engine.
Thanx again, looks like I have a new project...... Shep

 

[Don S]

Re: Water coming in boat

The shutters have absolutely nothing to do with your leak. The shutters do nothing but slow down water that sloshes up the exhaust tube, they DO NOT seal anything even resembleing water tight. There is usually about a 1/16 to 1/8" gap around the edge when they are closed. That exhaust Y always has water in it when the boat is in the water.

 

[jfcar]

Re: Water coming in boat

Check shift cable boot and drive shaft boot.
John

 

[Shep111]

Re: Water coming in boat

Thanx John, but that brings up a question...........boats on the trailer, I filled the bilge with water, plug in boat. If it was one of the boots water should be coming out of one of the boots,right? It's coming out of the lower holes, where I believe it's normally exhausted from the engine during operation. If one of the boots were leaking, how would the water get to where it is coming out?

 

[Haut Medoc]

Re: Water coming in boat

Thanx John, but that brings up a question...........boats on the trailer, I filled the bilge with water, plug in boat. If it was one of the boots water should be coming out of one of the boots,right? It's coming out of the lower holes, where I believe it's normally exhausted from the engine during operation. If one of the boots were leaking, how would the water get to where it is coming out?

The Y pipe joints are leaking somewhere or you have a hole rusted right through.....
You could test it by pulling a riser, pulling the drive & plugging the exhaust bellows & some corks in those holes & pour some water down the y pipe & observe.....
Y pipe replacement requires engine removal......

 

[bruceb58]

Re: Water coming in boat

I hope you didn't fill your bilge so high that you submerged your starter. if you did, it has to come off now.

 

[Don S]

Re: Water coming in boat

The fact is, if water came out the two 1" holes at the base of the transom shield, when water was put in the bilge, there is only one way for it to get there. It's either the exhaust Y, or the seal ring between the Y and transom shield, or the shield is damaged where the Y attaches.
Those two holes are idle relief to prevent excessive exhaust back pressure at idle.
And to do any repairs, requiers the engine to come out.