1986 OMC Cobra

[fluter52]

I have a 1986 OMC Cobra with a 3.0L 140hp inline GM 4 cyl. engine on a Rinker. We have had water leaking into the bilge area for several years. I have never been able to figure out where it is coming in. Today (with the boat out of water) I tilted the front end high and put water into the bilge area to see if I could see water coming out. Water was coming out of the annode area mounted under the plate that is attached to the transom. I removed the annode and there are two holes that go inside the boat. I suspect that is where the leak is but I don't know.<br />Any help would be greatly appreciated.

 

[cobra 3.0]

Re: 1986 OMC Cobra

I have the same problem. I can't see where the water can be coming in.

 

[loadnet]

Re: 1986 OMC Cobra

I have a mercruiser and I know they are different but I have to tell ya this story...<br /><br />I had a leak roughly in the same area that could NOT be detected until I removed the Engine and complete Gimbal Housing and Gimbal housing bracket.<br /><br />There was a small hole ROTTED right through the side of the gimbal housing which was hidden by the gimbal bracket. <br /><br />The outdrive and gimbal housing looked beautiful from the surface but sure as heck, it was rotted to death under the bracket..<br /><br />I sure hope you do not have to remove everything to find your problem leak.<br /><br />Good luck to you.

 

[andrewgroup]

Re: 1986 OMC Cobra

Is this a fiberglass boat with a plywood centered transom?<br /><br />Did the boat setup for a long period where water may have been able to set in the bilge and maybe the drain hole was plugged with debri?<br /><br />I had this and I have extensive pictures of the problem I had plus my fix for the problem.<br /><br />Basically what happened was the water was absorbed into the plywood transom and rotted and softened the wood outward about 8 inches from the drain hole. This allowed the lower two bolts mounting the large transom plate to that has a seal 360 degrees around to leak water under.<br /><br />Remove the drain plug plate and see if the wood you can penetrate the wood within the transom with a sharp pointed object. Test in all directions and any penetration beyond the bare tip of the object might indicate a water soaked transom....If I new how to add images to this board I would post images of my old problem.