Where is the water coming from?

[AQUA222]

I am forever in debt to the loyal classic aquasport responders on this forum..... So I present to you yet another issue I'm having with the " Morgan Joy". I'm getting a little, about one to two gallons of water in the bilge. At first I thought it was the below water line scuppers, but have since made removable plugs that I install before I launch. There is no visible leak at the bellows that ive noticed. The hull is in great shape for a 79, the plug in the transom fits nice and snug, and the 470 exhaust tube looked almost new condition when I installed the motor, where is the water coming from?

[fitz73222]

Since this is a MercCruiser, look for a crack or split in the intermediate bellows that connects from the upper drive unit housing to the gimble housing, water could enter the boat through the gimble housing via the opening at the driveshaft to engine coupler or this could be the water hose the comes gimble housing to the front of the water pump. I would run the 470 with the lid up and look for water slinging or dripping from the transom plate area. Odviously, you will need someone to drive the boat while do this. Also do the boat at rest (non running) and then running and see if it makes a difference in how much water. Also check the temp of the water. If its hot, look for an engine leak. If cold look for a leak in the transom plate area for water that hasn't entered the engine yet.

[AQUA222]

Fitz, thanks for the info, I'll check Sunday when I'm out.  The water is warm....and smells like exhaust. I never made the connection.  I'll do what you said about the cover and let you know how it goes. Thanks again

[fitz73222]

Sounds like you're half way there. Since your engine is freshwater cooled, the raw water flow (from the drive unit) circulates through the heat exchanger to cool the closed system water. Basically a radiator that has the raw water cooling it (instead of air flow like your car) all contained in a tank and then out through the exhaust manifold and back into the river. So laying on your stomach with a flash light on the port side of the engine, look for a leak in the heat exchanger tank, the bottom of the exhaust manifold were it bolts to the block,(there's a gasket there) the joint where manifold bolts to exhaust riser, (there's a gasket there) the rubber bellows that connects the riser to the transom plate and the bellows connection to the actual transom plate. Hopefully just a loose hose clamp on either of the rubber exhaust bellows connection points would be best case. Any increase of your engine temp that you've noticed on your gage?

[fitz73222]

You may actually be able to do this on the trailer with a flush attachment. Since your bilge is so spotless (very nice) you could rig up one one of those liquid fertilizer containers (Miracle Grow comes to mind) and make a batch of super purple food coloring and screw it line with your flush muffs and fire the engine up, run it at fast idle and watch for the drip to show up in your bilge and it may help you find out where the leak is. That purple will stick out like a sore thumb in that pretty white bilge and you eliminated the need to do this with a second person in the water.

[AQUA222]

Did 30 miles, fishing 6 hours , very little water in bilge, I guess I'll have to dye it like you suggested as there was no visible water from fittings or hoses while under way.