Sterndrive leak location - places to check?

[erikgreen]

Hi all;

I have a slow leak in my boat near the transom that I found last weekend, while the boat sat in a slip overnight for the first time.

Background info: Sea Ray SRV-210, new bellows in March, I use the exhaust tube instead of bellows. I rebuilt the stringers and deck in april/may, and last august I replaced the engine mounts, drain plug, and sealed the inside of the transom opening with epoxy. I replaced the transom seal when I re-installed the transom hardware, including replacing the aluminum bolts and zincs.

Over 18 hours about 6 inches of water leaked into a 20 foot boat (and my auto bilge switch stopped working... worked fine when tested... (#@$*%( *$#).

So I have a slow leak somewhere. I already have two places on my list to look, the lower shift cable boot and around the garboard plug housing.

Does anyone want to offer other places for me to look? I'm going to hook up a camera and TV display to take with me so I can look for the leak when it's in the water next weekend too, but it'd be nice to find something before then... there's nothing obvious leaking I can see with my bare eyes.

Erik

 

[BAYLINER185]

Re: Sterndrive leak location - places to check?

Erik

As you already know a stern drive leak is hard to spot. I feel your pain Ive been there my self right before the boating season.

SINCE you did pull the motor and doa transom seal I would 1st look at your Y pipe and see if its leaking. There is an O ring that can go bad and begin to leak. So start there. Its one of those hard to see things you almost need to be on your knees in the bildge to see it so the camera may be a good idea.

I would then look at the bellows and make sure they are installed right even though you say they are new you never know.

On my boat after all the trouble and thinking its this and that leaking we found my leak was the upper swivel pin seal. This is basicly the main hinge that lets your drive turn side to side. They ware out over time and for as your boat being about as old as mine its quite possible thats the leak. ITS NOT EASY to fix and everything Ive said to check needs to come apart to fix the leak. When my swivel pin was leaking the water would run down and drip all over my Y pipe making it look like the Y pipe was leaking when it wasnt. You neede to see if you see water dripping down or runnin in on the drive shaft if it is its problalbly the swival pin seal.

Those are the main places I would check on the transom. NOW its possible that you have a through hull fittign leaking and water is runign back to the bildge as its the lowest position on the boat when in the water. It may be a leak somewhere forward of the transom leaking and filling the bildge.

Im not sure if your 21 footer is more then just an OPEN bow ski boat or not where it may have a few through hull fittings that may be leaking.

Leaks on boats are not easy to find but if you take your time and try to be as through as possible you will nail it down.

 

[erikgreen]

Re: Sterndrive leak location - places to check?

Thanks for the info and the vote of confidence.

I think I'll start with the bellows, and make sure I don't have any obvious leaks there, and probably drop the drive to check for evidence of water on the input shaft and yoke.

After that I'll probably remove and re-seal the garboard drain plug, which is my only through hull at the waterline at this point. It may be ok, but it won't take long and won't hurt.

Then I'll get the camera ready and take it with me this weekend, so I can check while I'm on the water.

At least now that my bilge pump switch is working it's not dangerous, just annoying.

Erik

 

[jaxnjil]

Re: Sterndrive leak location - places to check?

erik; PLEASE post what you find. l to am trying to find a leak. it not as large as yours, 1 gal to 1 1/2 per 24 hr, but its driving me nuts. so far i'v changed and since double checked bellows and removed cleaned and resealed all through hull fitting. will try to ck exhaust as 185 said.
hope you dont mind me tagging along on your thread

 

[ne7800]

Re: Sterndrive leak location - places to check?

I found my leak at the gasket where the hydrolic lines for the trim enter the out drive just another place to check

 

[erikgreen]

Re: Sterndrive leak location - places to check?

Good info 7800, thanks.

No problems tagging along here, maybe we can get people to post a list of obscure places that they've found leaks.

Erik

 

[erikgreen]

Re: Sterndrive leak location - places to check?

Okay, I did a bit of work tonight, what I found so far:

I replaced the garboard plug receptacle, it may have been fine but this time I made sure I used 5200 everywhere, including the screw holes. When I took one screw out it let out a few drops of water, so I think that one went all the way through, which is probably part of the issue. Hopefully the 5200 will seal it well if it was.

I also found that one of my plug wires was trapped inside the hose clamp in back of the power steering oil cooler! It must have slipped inside when I did the draining last fall, and got cinched into place there. I don't know if it was leaking (it was pretty squished) but I'm not happy with that plug wire and its flat spot now... I'm leaning away from it being the problem since it would have only dripped a lot when the engine was running, and I think I took on most of the water last weekend sitting in the slip.

I also did manage to get my points, condenser, rotor, distributor cap and coil replaced tonight, so at least if it's still leaking it should run better

More info after this weekend,

Erik

 

[gamarines2]

Re: Sterndrive leak location - places to check?

My leak turned out to be shift cable bellows. Far easier to replace than drive shaft bellows, so don't be intimidated.

Jake